[ { "id": "https://authors.library.caltech.edu/records/79c0g-6br20", "eprint_status": "archive", "datestamp": "2023-12-12 17:31:10", "lastmod": "2023-12-12 17:31:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Reed-Jillian-T", "name": { "family": "Reed", "given": "Jillian T." }, "orcid": "0009-0005-2814-8415" }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Byrne-Sean-T", "name": { "family": "Byrne", "given": "Sean T." }, "orcid": "0000-0002-5466-3112" }, { "id": "Lin-Shaoyang", "name": { "family": "Lin", "given": "Shaoyang" }, "orcid": "0000-0003-4108-7299" }, { "id": "Ye-Alexandre-Z", "name": { "family": "Ye", "given": "Alexandre Z." }, "orcid": "0009-0003-4895-0160" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Spontaneous mesostructure formation produces optically transmissive Ni\u2013P films that are catalytically active for the photoelectrochemical hydrogen evolution reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment", "note": "
\u00a9 The Royal Society of Chemistry 2023.
\n\nThis work was supported by U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and under Award Number DE-SC0022087. XPS and UV-Vis data were collected at the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. M. C. M. acknowledges the Resnick Sustainability Institute at Caltech for fellowship support.
\n\nNSL is a scientific founder of and consultant to a company, H2U Technologies, that is developing catalysts and electrolyzers for the production of hydrogen.
", "abstract": "Ni\u2013P films that are catalytically active for the hydrogen-evolution reaction were electrodeposited onto photoactive Si substrates between 20 \u00b0C and 80 \u00b0C from an aqueous solution. Ni\u2013P films deposited at 20 \u00b0C and exposed to acidic environments spontaneously developed deep cracks. A substantial increase in optical transmission to the semiconducting substrate resulted without affecting the catalytic performance of the film. In contrast, Ni\u2013P films deposited at 80 \u00b0C only developed minor surface-level cracks and did not exhibit a substantial increase in optical transmission. During electrodeposition of the Ni\u2013P films at low temperatures, the uptake of parasitically evolved hydrogen generated partially defective Ni\u2013P, causing crack formation. Increases in the temperature of the electrodeposition bath increased the faradaic efficiency of Ni\u2013P deposition and consequently reduced the uptake of parasitically generated hydrogen. The defective Ni\u2013P films were converted to a crack-resistant material by thermally desorbing the excess hydrogen that was absorbed during the low-temperature electrodeposition process.
", "date": "2023-09-21", "date_type": "published", "publication": "Sustainable Energy & Fuels", "volume": "7", "number": "18", "publisher": "Royal Society of Chemistry", "pagerange": "4401-4406", "issn": "2398-4902", "official_url": "https://authors.library.caltech.edu/records/79c0g-6br20", "funders": { "items": [ { "grant_number": "DE-SC0004993" }, { "grant_number": "DE-SC0022087" }, { "grant_number": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d3se00378g", "primary_object": { "basename": "d3se00378g1.pdf", "url": "https://authors.library.caltech.edu/records/79c0g-6br20/files/d3se00378g1.pdf" }, "pub_year": "2023", "author_list": "Ifkovits, Zachary P.; Reed, Jillian T.; et el." }, { "id": "https://authors.library.caltech.edu/records/gtcgp-kp430", "eprint_status": "archive", "datestamp": "2023-12-08 22:48:57", "lastmod": "2023-12-08 22:49:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Statt-Michael-J", "name": { "family": "Statt", "given": "Michael J." }, "orcid": "0000-0002-7923-6029" }, { "id": "Rohr-Brian-A", "name": { "family": "Rohr", "given": "Brian A." }, "orcid": "0000-0003-4696-0149" }, { "id": "Brown-Kris", "name": { "family": "Brown", "given": "Kris" } }, { "name": { "family": "Guevarra", "given": "Dan" } }, { "id": "Hummelsh\u00f8j-Jens", "name": { "family": "Hummelsh\u00f8j", "given": "Jens" } }, { "id": "Hung-Linda", "name": { "family": "Hung", "given": "Linda" }, "orcid": "0000-0002-1578-6152" }, { "id": "Anapolsky-Abraham", "name": { "family": "Anapolsky", "given": "Abraham" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" } ] }, "title": "ESAMP: event-sourced architecture for materials provenance management and application to accelerated materials discovery", "ispublished": "pub", "full_text_status": "public", "keywords": "General Medicine", "note": "This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
\n\nThe development and implementation of the architecture were supported by the Toyota Research Institute through the Accelerated Materials Design and Discovery program. Generation of all experimental data was supported by the Joint Center for Artificial Photosynthesis, a US Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under Award Number DE-SC0004993. The development of the catalyst discovery use case was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DESC0020383. The authors thank Dr Edwin Soedarmadji for stewardship of MEAD and all members of the JCAP High Throughput Experimentation group for the generation of the data. The authors thank Daniel Schweigert for providing insights into standard database management practices. The authors thank Thomas E. Morell for facilitating implementation of DOI-based linkages between MPS and CaltechDATA.
\n\nThe entire MEAD data stored in ESAMP provenance is available in a PostgreSQL database. This format requires three steps to make use of: download the compressed SQL database dump file (.tar.gz format) from https://data.caltech.edu/records/hjfx4-a8r81; install PostgreSQL by following the instructions here; extract the .tar.gz file, which will yield a .sql file; follow the PostgreSQL documentation to create a new database from the .sql file. This will create a local copy of the database that we present in this work. The data can be browsed using the DBeaver user. Our docker container scripts to setup the database are provided here: https://github.com/modelyst/mps-docker. Database generation code: the database discussed in this manuscript was generated using the custom built DBgen tool: https://github.com/modelyst/dbgen/. Code to generate Fig. 5: all the scripts used to generate this figure are available at https://github.com/TRI-AMDD/ESAMP-usecase. The notebook 'query_and_modeling.ipynb' was used to generate the results and visualizations. The associated database queries are made available in eche_forms_query.sql and eche_pets_query.sql. In addition helper scripts such as myquaternaryulitity.py, myternaryutility.py, quaternary_faces_shells.py are provided to aid in visualization.
\n\nModelyst LLC implements custom data management systems in a professional context.
", "abstract": "While the vision of accelerating materials discovery using data driven methods is well-founded, practical realization has been throttled due to challenges in data generation, ingestion, and materials state-aware machine learning. High-throughput experiments and automated computational workflows are addressing the challenge of data generation, and capitalizing on these emerging data resources requires ingestion of data into an architecture that captures the complex provenance of experiments and simulations. In this manuscript, we describe an event-sourced architecture for materials provenance (ESAMP) that encodes the sequence and interrelationships among events occurring in a simulation or experiment. We use this architecture to ingest a large and varied dataset (MEAD) that contains raw data and metadata from millions of materials synthesis and characterization experiments performed using various modalities such as serial, parallel, multi-modal experimentation. Our data architecture tracks the evolution of a material's state, enabling a demonstration of how state-equivalency rules can be used to generate datasets that significantly enhance data-driven materials discovery. Specifically, using state-equivalency rules and parameters associated with state-changing processes in addition to the typically used composition data, we demonstrated marked reduction of uncertainty in prediction of overpotential for oxygen evolution reaction (OER) catalysts. Finally, we discuss the importance of ESAMP architecture in enabling several aspects of accelerated materials discovery such as dynamic workflow design, generation of knowledge graphs, and efficient integration of simulation and experiment.
", "date": "2023-08-01", "date_type": "published", "publication": "Digital Discovery", "volume": "2", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "1078-1088", "issn": "2635-098X", "official_url": "https://authors.library.caltech.edu/records/gtcgp-kp430", "funders": { "items": [ { "agency": "Toyota Research Institute", "grant_number": "Accelerated Materials Design and Discovery Program" }, { "grant_number": "DE-SC0004993" }, { "grant_number": "DE-SC0020383" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "JCAP" } ] }, "doi": "10.1039/d3dd00054k", "primary_object": { "basename": "d3dd00054k.pdf", "url": "https://authors.library.caltech.edu/records/gtcgp-kp430/files/d3dd00054k.pdf" }, "related_objects": [ { "basename": "d3dd00054k1.pdf", "url": "https://authors.library.caltech.edu/records/gtcgp-kp430/files/d3dd00054k1.pdf" }, { "basename": "d3dd00054k2.pdf", "url": "https://authors.library.caltech.edu/records/gtcgp-kp430/files/d3dd00054k2.pdf" }, { "basename": "d3dd00054k3.pdf", "url": "https://authors.library.caltech.edu/records/gtcgp-kp430/files/d3dd00054k3.pdf" }, { "basename": "d3dd00054k4.pdf", "url": "https://authors.library.caltech.edu/records/gtcgp-kp430/files/d3dd00054k4.pdf" } ], "pub_year": "2023", "author_list": "Statt, Michael J.; Rohr, Brian A.; et el." }, { "id": "https://authors.library.caltech.edu/records/6fqp8-y9536", "eprint_status": "archive", "datestamp": "2023-12-11 19:24:05", "lastmod": "2023-12-11 19:24:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Statt-Michael-J", "name": { "family": "Statt", "given": "Michael J." }, "orcid": "0000-0002-7923-6029" }, { "id": "Rohr-Brian-A", "name": { "family": "Rohr", "given": "Brian A." }, "orcid": "0000-0003-4696-0149" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Breeden-Ja'Nya", "name": { "family": "Breeden", "given": "Ja'Nya" }, "orcid": "0000-0002-2150-5572" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "The materials experiment knowledge graph", "ispublished": "pub", "full_text_status": "public", "keywords": "General Medicine", "note": "This article is licensed under a Creative Commons Attribution 3.0 Unported Licence.
\n\nThis material is primarily based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. Development of the graph database schema was supported by Toyota Research Institute. Much of the underlying data was generated by research in the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Storage is provided by the Open Storage Network via XSEDE allocation INI210004.
\n\nM. J. S., B. A. R., D. G., S. K. S., and J. M. G. designed the MekG and the use cases. M. J. S. and B. A. R. implemented MekG with assistance from D. G. and J. M. G. J. B. and D. G. implemented the design of experiments use case.
\n\nThe MPS SQL database from which MekG is built and the three sub-databases are available at https://data.caltech.edu/records/aeffy-dcr62 (doi: https://doi.org/10.22002/aeffy-dcr62). The MekG neo4j database is available at https://data.caltech.edu/records/h88fq-dk449 (doi: https://doi.org/10.22002/h88fq-dk449).
\n\nThe code for the query time use cases and MekG migration from MPS is available at https://github.com/modelyst/MekG-migrations. The code for the design of experiments and hypothesis evaluation use cases is available at https://data.caltech.edu/records/m4mpa-4mt17 (doi: https://doi.org/10.22002/m4mpa-4mt17).
\n\nModelyst LLC implements custom data management systems in a professional context.
", "abstract": "Materials knowledge is inherently hierarchical. While high-level descriptors such as composition and structure are valuable for contextualizing materials data, the data must ultimately be considered in the context of its low-level acquisition details. Graph databases offer an opportunity to represent hierarchical relationships among data, organizing semantic relationships into a knowledge graph. Herein, we establish a knowledge graph of materials experiments whose construction encodes the complete provenance of each material sample and its associated experimental data and metadata. Additional relationships among materials and experiments further encode knowledge and facilitate data exploration. We illustrate the Materials Experiment Knowledge Graph (MekG) using several use cases, demonstrating the value of modern graph databases for the enterprise of data-driven materials science.
", "date": "2023-08", "date_type": "published", "publication": "Digital Discovery", "volume": "2", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "909-914", "issn": "2635-098X", "official_url": "https://authors.library.caltech.edu/records/6fqp8-y9536", "funders": { "items": [ { "grant_number": "DE-SC0021266" }, { "grant_number": "Toyota Research Institute" }, { "grant_number": "DE-SC0004993" }, { "grant_number": "INI210004" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "JCAP" } ] }, "doi": "10.1039/d3dd00067b", "primary_object": { "basename": "d3dd00067b1.pdf", "url": "https://authors.library.caltech.edu/records/6fqp8-y9536/files/d3dd00067b1.pdf" }, "related_objects": [ { "basename": "d3dd00067b.pdf", "url": "https://authors.library.caltech.edu/records/6fqp8-y9536/files/d3dd00067b.pdf" } ], "pub_year": "2023", "author_list": "Statt, Michael J.; Rohr, Brian A.; et el." }, { "id": "https://authors.library.caltech.edu/records/hjj9f-g4828", "eprint_id": 121448, "eprint_status": "archive", "datestamp": "2023-09-15 07:50:50", "lastmod": "2023-12-21 23:42:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Statt-Michael-J", "name": { "family": "Statt", "given": "Michael J." }, "orcid": "0000-0002-7923-6029" }, { "id": "Rohr-Brian-A", "name": { "family": "Rohr", "given": "Brian A." }, "orcid": "0000-0003-4696-0149" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Morrell-Thomas-E", "name": { "family": "Morrell", "given": "Thomas E." }, "orcid": "0000-0001-9266-5146" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "The Materials Provenance Store", "ispublished": "pub", "full_text_status": "public", "keywords": "Library and Information Sciences; Statistics, Probability and Uncertainty; Computer Science Applications; Education; Information Systems; Statistics and Probability", "note": "\u00a9 The Author(s) 2023. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. This material is primarily based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. Development of the database schema was supported by Toyota Research Institute. Much of the underlying data was generated by research in the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Storage was provided by the Open Storage Network via XSEDE allocation INI210004. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515. Contributions. M.J.S., B.A.R., D.G., S.K. and J.M.G. designed the MPS schema and its ingestion of MEAD. M.J.S., B.A.R. and D.G. implemented MPS. T.E.M. facilitated implementation of DOI-based linkages between MPS and CaltechDATA. Quality checks were performed by all authors. M.J.S., B.A.R. and J.M.G. were the primary authors of the manuscript. Code availability. The MPS database was generated using DBgen (v1.0.0a7) (https://github.com/modelyst/dbgen), an open-source framework for building scientific databases and pipelines available at https://github.com/modelyst/dbgen. A python API, a command-line interface (CLI), and a Jupyter notebook with example queries are available in the Materials Provenance Store Client repository (https://github.com/modelyst/mps-client). Competing interests. Modelyst LLC implements custom data management systems in a professional context.
\n\nPublished - 41597_2023_Article_2107.pdf
Supplemental Material - 41597_2023_2107_MOESM1_ESM.xlsx
", "abstract": "We present a database resulting from high throughput experimentation, primarily on metal oxide solid state materials. The central relational database, the Materials Provenance Store (MPS), manages the metadata and experimental provenance from acquisition of raw materials, through synthesis, to a broad range of materials characterization techniques. Given the primary research goal of materials discovery of solar fuels materials, many of the characterization experiments involve electrochemistry, along with optical, structural, and compositional characterizations. The MPS is populated with all information required for executing common data queries, which typically do not involve direct query of raw data. The result is a database file that can be distributed to users so that they can independently execute queries and subsequently download the data of interest. We propose this strategy as an approach to manage the highly heterogeneous and distributed data that arises from materials science experiments, as demonstrated by the management of over 30 million experiments run on over 12 million samples in the present MPS release.", "date": "2023-04-06", "date_type": "published", "publication": "Scientific Data", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "184", "id_number": "CaltechAUTHORS:20230519-1502000.6", "issn": "2052-4463", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230519-1502000.6", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "Caltech-Library" }, { "id": "Liquid-Sunlight-Alliance" }, { "id": "JCAP" } ] }, "doi": "10.1038/s41597-023-02107-0", "pmcid": "PMC10079965", "primary_object": { "basename": "41597_2023_Article_2107.pdf", "url": "https://authors.library.caltech.edu/records/hjj9f-g4828/files/41597_2023_Article_2107.pdf" }, "related_objects": [ { "basename": "41597_2023_2107_MOESM1_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/hjj9f-g4828/files/41597_2023_2107_MOESM1_ESM.xlsx" } ], "pub_year": "2023", "author_list": "Statt, Michael J.; Rohr, Brian A.; et el." }, { "id": "https://authors.library.caltech.edu/records/2wq8x-nwd98", "eprint_id": 118942, "eprint_status": "archive", "datestamp": "2023-08-22 18:26:43", "lastmod": "2023-10-24 23:46:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Morla-Maureen-B", "name": { "family": "Morla", "given": "Maureen B." }, "orcid": "0000-0002-2520-9543" }, { "id": "Pham-Kim-H", "name": { "family": "Pham", "given": "Kim H." } }, { "id": "Dowling-Jacqueline-A", "name": { "family": "Dowling", "given": "Jacqueline A." }, "orcid": "0000-0001-5642-8960" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Powdered Mn_(y)Sb_(1-y)O_(x) Catalysts for Cerium-Mediated Oxygen Evolution in Acidic Environments", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Energy Engineering and Power Technology; Fuel Technology; Renewable Energy, Sustainability and the Environment; Chemistry (miscellaneous)", "note": "This work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award number DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. XPS and DRS data were collected at the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. ICP-MS instrumentation at the Resnick Sustainability Institute's Water and Environment Lab at the California Institute of Technology was used in this work. We thank Madeline C. Meier for assistance with illustrations and schematic design and Dr. Nathan Dalleska for assistance with the ICP-MS.", "abstract": "Mn_(y)Sb_(1-y)O_(x) powders with a series of compositions were evaluated as catalysts for chemical water oxidation in aqueous perchloric, sulfuric, or methanesulfonic acid. O\u2082(g) evolved spontaneously over Mn_(y)Sb_(1-y)O_(x) catalyst powders that had been suspended in solutions that were pre-loaded with Ce\u2074\u207a ions. The rate of O\u2082 evolution depended on the amount, as well as the oxidation state, of the Mn in the powder. The highest O\u2082 evolution rate was observed from the most Mn-rich catalyst, which had an effective surface oxidation state of Mn\u00b2\u22c5\u2079\u207a in its rest state. The facile synthetic accessibility of such catalysts in powder form constitutes a step toward replacing Ir or Ru in Ce-mediated oxygen evolution in decoupled water splitting systems, as well as toward developing inks of earth-abundant catalysts for preparation of catalyst-coated membranes used in conventional proton-exchange membrane electrolyzers.", "date": "2022-12-09", "date_type": "published", "publication": "ACS Energy Letters", "volume": "7", "number": "12", "publisher": "American Chemical Society", "pagerange": "4258-4264", "id_number": "CaltechAUTHORS:20230125-514893900.22", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230125-514893900.22", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.2c01754", "pub_year": "2022", "author_list": "Ifkovits, Zachary P.; Evans, Jake M.; et el." }, { "id": "https://authors.library.caltech.edu/records/83tv1-p3k51", "eprint_id": 115079, "eprint_status": "archive", "datestamp": "2023-08-22 17:20:19", "lastmod": "2023-10-24 15:23:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Segev-Gideon", "name": { "family": "Segev", "given": "Gideon" }, "orcid": "0000-0002-6175-3458" }, { "name": { "family": "Kibsgaard", "given": "Jakob" }, "orcid": "0000-0002-9219-816X" }, { "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "name": { "family": "Xu", "given": "Zhichuan J." }, "orcid": "0000-0001-7746-5920" }, { "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "name": { "family": "Deutsch", "given": "Todd G." }, "orcid": "0000-0001-6577-1226" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "name": { "family": "Zhang", "given": "Jenny Z." }, "orcid": "0000-0003-4407-5621" }, { "name": { "family": "Hammarstrom", "given": "Leif" }, "orcid": "0000-0002-9933-9084" }, { "name": { "family": "Nocera", "given": "Daniel G." }, "orcid": "0000-0001-5055-320X" }, { "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" }, { "name": { "family": "Agbo", "given": "Peter" }, "orcid": "0000-0003-3066-4791" }, { "name": { "family": "Hisatomi", "given": "Takashi" }, "orcid": "0000-0002-5009-2383" }, { "name": { "family": "Osterloh", "given": "Frank E." }, "orcid": "0000-0002-9288-3407" }, { "name": { "family": "Domen", "given": "Kazunari" }, "orcid": "0000-0001-7995-4832" }, { "name": { "family": "Abdi", "given": "Fatwa F." }, "orcid": "0000-0001-5631-0620" }, { "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "name": { "family": "Miller", "given": "Daniel J." } }, { "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "name": { "family": "McIntyre", "given": "Paul C." }, "orcid": "0000-0002-7498-831X" }, { "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" }, { "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry" }, "orcid": "0000-0001-9435-0201" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "name": { "family": "Ertem", "given": "Mehmed Z." }, "orcid": "0000-0003-1994-9024" }, { "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "name": { "family": "Choi", "given": "Kyoung-Shin" }, "orcid": "0000-0003-1945-8794" }, { "name": { "family": "Lee", "given": "Jae Sung" } }, { "name": { "family": "Ishitani", "given": "Osamu" }, "orcid": "0000-0001-9557-7854" }, { "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" }, { "name": { "family": "Prabhakar", "given": "Rajiv Ramanujam" }, "orcid": "0000-0002-4598-9073" }, { "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" }, { "name": { "family": "Boettcher", "given": "Shannon W." }, "orcid": "0000-0001-8971-9123" }, { "name": { "family": "Vincent", "given": "Kylie" }, "orcid": "0000-0001-6444-9382" }, { "name": { "family": "Takanabe", "given": "Kazuhiro" }, "orcid": "0000-0001-5374-9451" }, { "name": { "family": "Artero", "given": "Vincent" }, "orcid": "0000-0002-6148-8471" }, { "name": { "family": "Napier", "given": "Ryan" }, "orcid": "0000-0003-1602-7825" }, { "name": { "family": "Roldan Cuenya", "given": "Beatriz" }, "orcid": "0000-0002-8025-307X" }, { "name": { "family": "Koper", "given": "Marc T. M." }, "orcid": "0000-0001-6777-4594" }, { "name": { "family": "van de Krol", "given": "Roel" }, "orcid": "0000-0003-4399-399X" }, { "name": { "family": "Houle", "given": "Frances" }, "orcid": "0000-0001-5571-2548" } ] }, "title": "The 2022 solar fuels roadmap", "ispublished": "pub", "full_text_status": "public", "keywords": "Surfaces, Coatings and Films; Acoustics and Ultrasonics; Condensed Matter Physics; Electronic, Optical and Magnetic Materials", "note": "\u00a9 2022 The Author(s). Published by IOP Publishing Ltd.\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.\n\nReceived 5 November 2021;\nAccepted 13 May 2022;\nPublished 22 June 2022.\n\nAcknowledgments:\n1. Introduction\n\nGideon Segev, Roel van de Krol and Frances Houle\n\nG S thanks the Azrieli Foundation for financial support within the Azrieli Fellows program. R V D K gratefully acknowledges financial support from the German Research Foundation (PAK 981), the German Federal Ministry of Education and Research (BMBF Project Nos. 033RC021C and 03SF0619C) and the EU Horizon 2020 program ('Sun-to-X', Grant Agreement No. 883264). F A H: This material is based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266.\n\n2. Comparison of state of the art electrocatalysts for water splitting, CO2 reduction, and N2 reduction\n\nJakob Kibsgaard, Christopher Hahn and Zhichuan J Xu\n\nJ K gratefully acknowledges funding from the Carlsberg Foundation Grant CF18-0435. Work by C H was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344 and was supported by Laboratory Directed Research and Development funding under Project 19-SI-005. Z X thanks the funding support by the Singapore National Research Foundation under its Campus for Research Excellence and Technological Enterprise (CREATE) programme, through eCO2EP programmes.\n\n3. Efficiency and stability benchmarking. What is required to bring a solar fuels system to market?\n\nWen-Hui (Sophia) Cheng, Todd G Deutsch and Chengxiang Xiang\n\nC X acknowledge the support from the Fuel Cell Technologies Office, of the U. S. Department of Energy, Energy Efficiency and Renewable Energy under Contract Number DE-EE0008092 and from SoCalGas under Award Number 5660060287. C X and W-H C acknowledge the support of the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266 for the Liquid Sunlight Alliance program. W-H C also acknowledges the support from Ministry of Science and Technology (2030 Cross-Generation Young Scholars Program, Grant Number: 110-2628-E-006-005), Taiwan and Ministry of Education (Yushan Scholar Program), Taiwan, and in part from the Higher Education Sprout Project of the Ministry of Education to the Headquarters of University Advancement at National Cheng Kung University (NCKU). T G D acknowledges support from the HydroGEN Advanced Water Splitting Materials Consortium, established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under Award Number DE-EE-0008084. T G D also acknowledges support from the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy under Contract Number DE-AC36-08GO28308. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes.\n\n4. Comparing artificial and natural photosynthesis\u2014bio concepts and hybrid systems\n\nJenny Z Zhang, Leif Hammarstr\u00f6m and Daniel G Nocera\n\nJ Z would like to acknowledge the UK Biotechnology and Biological Sciences Research Council (BB/R011923/1). D G N acknowledges support from the U.S. Department of Energy (DE-SC0017619) and generous support from the TomKat Foundation.\n\n5. Design and scale-up of solar fuels systems using current technologies\u2014neutral pH, vapor-fed devices\n\nAdam Z Weber and Peter Agbo\n\nA Z W and P A acknowledge support by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266 and the Joint Center for Artificial Photosynthesis (A Z W, P A) under Award Number DE-SC0004993.\n\n6. Particle-based systems: lessons learned and guidelines for large area systems\n\nTakashi Hisatomi, Frank E Osterloh and Kazunari Domen\n\nK D acknowledges financial supports from New Energy and Industrial Technology Development Organization (NEDO), Japan (Project Number P14002). T H acknowledges support from Japan Science and Technology Agency (JST)-PRESTO, Japan (Grant Number JPMJPR20T9). F E O acknowledges support from the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DOE-SC0015329.\n\n7. Device design considerations for scale-up: managing photons, electrons, and ions\n\nFatwa F Abdi and Sophia Haussener\n\nThis material is based upon work performed with the financial support of a Starting Grant of the Swiss National Science Foundation, as part of the SCOUTS project (Grant #155876). F F A gratefully acknowledges financial support from the German Research Foundation under Germany's Excellence Strategy\u2014EXC 2008/1 (UniSysCat)\u2014390540038, the German Helmholtz Association\u2014Excellence Network\u2014ExNet-0024-Phase2-3, and the German Bundesministerium f\u00fcr Bildung und Forschung (BMBF), project 'H2Demo' (No. 03SF0619A-K).\n\n8. Membranes for solar fuels\n\nDaniel J Miller and Shane Ardo\n\nThis material is based upon work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC00493. This material is also based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266.\n\n9. Photoelectrodes based on conventional semiconductors (silicon, III\u2013V)\n\nPaul C McIntyre, Thomas Hannappel and Shu Hu\n\nS H gratefully acknowledges the financial support provided by the Division of Chemical Sciences, Geosciences and Biosciences, Office of Basic Energy Sciences, of the US Department of Energy through Grant No. DE-SC0021953, and the financial support of a Scialog program sponsored jointly by Research Corporation for Science Advancement and the Alfred P Sloan Foundation through a grant to Yale University by the Thistledown Foundation. P C M gratefully acknowledges the financial support of the National Science Foundation Award No. CBET-1805084. T H gratefully acknowledges financial support of the German Research Foundation PAK 981, 3096/10 and 3096/19, and the German Federal Ministry of Education and Research (BMBF Project Nos. 033RC021A and 03SF0619I).\n\n10. Nanostructures for light management in solar fuels and photoelectrochemistry\n\nWen-Hui (Sophia) Cheng and Harry Atwater\n\nThe authors acknowledge the support of the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266 for the Liquid Sunlight Alliance program. W-H C also acknowledges the support from Ministry of Science and Technology (2030 Cross-Generation Young Scholars Program, Grant Number: 110-2628-E-006-005), Taiwan and Ministry of Education (Yushan Scholar Program), Taiwan, and in part from the Higher Education Sprout Project of the Ministry of Education to the Headquarters of University Advancement at National Cheng Kung University (NCKU).\n\n11. Accelerating discovery of photoactive materials\n\nJohn M Gregoire and Mehmed Z Ertem\n\nThe authors of this roadmap acknowledge support from the Liquid Sunlight Alliance, LiSA, (to J M G) and from the Center for Hybrid Approaches in Solar Energy to Liquid Fuels, CHASE, (to M Z E). LiSA (Award DE-SC0021266) and CHASE (Award DE-SC0021173) are Fuels from Sunlight Hubs supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences.\n\n12. From materials discovery to functional photoelectrodes\n\nIan D Sharp, Kyoung-Shin Choi and Jae Sung Lee\n\nI D S acknowledges support from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (Grant Agreement No. 864234) and the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) under Germany\u00b4s Excellence Strategy\u2014EXC 2089/1-390776260. K-S C acknowledge the support from the Division of Chemical Sciences, Geosciences, and Biosciences, Office of Basic Energy Sciences of the U.S. Department of Energy through Grant DE-SC0008707. J S L acknowledges supports from Korean Ministry of Science and ICT through Grants of NRF-2019M1A2A2065612 and NRF-2018R1A2A1A05077909.\n\n13. Molecular photoreduction and photocatalysts on photofunctional solid materials\n\nOsamu Ishitani\n\nFunding from the Japan Society for the Promotion of Science (KAKENHI Grant Numbers JP20H00396 and JP17H06440 in Scientific Research on Innovative Areas 'Innovations for Light-Energy Conversion (I4LEC))' is acknowledged.\n\n14. Photocathode design: fundamental challenges and paths forward for CO2 reduction\n\nJoel W Ager and Rajiv Ramanujam Prabhakar\n\nThis material is based upon work performed by the Liquid Sunlight Alliance, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Rajiv Ramanujam Prabhakar acknowledges the Swiss National Science Foundation Early Postdoc Mobility Fellowship (191299) for financial support.\n\n15. Oxygen evolution reaction: catalysts, mechanisms, and durability\n\nAlexis T Bell and Shannon W Boettcher\n\nA T B and S W B acknowledge support from the Liquid Solar Alliance (LiSA), a Fuels from Sunlight Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0021266.\n\n16. Remaining challenges for the hydrogen evolution reaction (HER): catalysts and mechanism\n\nKylie Vincent, Kazuhiko Takanabe and Vincent Artero\n\nK A V is grateful for funding from the UK Biotechnology and Biological Sciences Research Council (BB/R018413/1) and the European Research Council (ERC-2018-CoG BiocatSusChem 819580). K T acknowledges support from the Mohammed bin Salman Center for Future Science and Technology for Saudi-Japan Vision 2030 at The University of Tokyo (MbSC2030). V A gratefully acknowledges the French National Research Agency (Labex ARCANE, CBH-EUR-GS, ANR-17-EURE-0003, BEEP, ANR-18-CE05-0017-05) and the European Union's Horizon 2020 research and innovation programme under Grant Agreement n\u00b0 883264 (project sun-to-X). Professor K Maeda (Tokyo Institute of Technology) is kindly acknowledged for the original TEM shown in figure 29(d).\n\n17. CO2RR catalysis: surface reactivity and products selectivity\n\nRyan Napier, Beatriz Roldan Cuenya and Marc T M Koper\n\nR N and M T M K acknowledge financial support from the Advanced Research Center for Chemical Building Blocks, ARC CBBC, which is co-founded and co-financed by the Dutch Research Council (NWO) and the Netherlands Ministry of Economic Affairs and Climate Policy. B R C appreciates funding by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)\u2014Project No. 406944504\u2014SPP 2080.\n\nData availability statement:\nNo new data were created or analysed in this study.\n\nPublished - Segev_2022_J._Phys._D__Appl._Phys._55_323003.pdf
", "abstract": "Renewable fuel generation is essential for a low carbon footprint economy. Thus, over the last five decades, a significant effort has been dedicated towards increasing the performance of solar fuels generating devices. Specifically, the solar to hydrogen efficiency of photoelectrochemical cells has progressed steadily towards its fundamental limit, and the faradaic efficiency towards valuable products in CO\u2082 reduction systems has increased dramatically. However, there are still numerous scientific and engineering challenges that must be overcame in order to turn solar fuels into a viable technology. At the electrode and device level, the conversion efficiency, stability and products selectivity must be increased significantly. Meanwhile, these performance metrics must be maintained when scaling up devices and systems while maintaining an acceptable cost and carbon footprint. This roadmap surveys different aspects of this endeavor: system benchmarking, device scaling, various approaches for photoelectrodes design, materials discovery, and catalysis. Each of the sections in the roadmap focuses on a single topic, discussing the state of the art, the key challenges and advancements required to meet them. The roadmap can be used as a guide for researchers and funding agencies highlighting the most pressing needs of the field.", "date": "2022-08-11", "date_type": "published", "publication": "Journal of Physics D: Applied Physics", "volume": "55", "number": "32", "publisher": "IOP", "pagerange": "Art. No. 323003", "id_number": "CaltechAUTHORS:20220608-849360000", "issn": "0022-3727", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220608-849360000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Azrieli Foundation" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "PAK 981" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "033RC021C" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03SF0619C" }, { "agency": "European Research Council (ERC)", "grant_number": "883264" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Carlsberg Foundation", "grant_number": "CF18-0435" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC52-07NA27344" }, { "agency": "Lawrence Livermore National Laboratory", "grant_number": "19-SI-005" }, { "agency": "National Research Foundation (Singapore)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0008092" }, { "agency": "Southern California Gas Company", "grant_number": "5660060287" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "110-2628-E-006-005" }, { "agency": "Ministry of Education (Taipei)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE-0008084" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" }, { "agency": "Biotechnology and Biological Sciences Research Council (BBSRC)", "grant_number": "BB/R011923/1" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0017619" }, { "agency": "Tomkat Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "New Energy and Industrial Technology Development Organization (NEDO)", "grant_number": "P14002" }, { "agency": "Japan Science and Technology Agency", "grant_number": "JPMJPR20T9" }, { "agency": "Department of Energy (DOE)", "grant_number": "DOE-SC0015329" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "155876" }, { "agency": "Helmholtz-Gemeinschaft Deutscher Forschungszentren (HGF)", "grant_number": "ExNet-0024-Phase2-3" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "390540038" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03SF0619A-K" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00493" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021953" }, { "agency": "Research Corporation" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Thistledown Foundation" }, { "agency": "NSF", "grant_number": "CBET-1805084" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "3096/10" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "3096/19" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "033RC021A" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03SF0619I" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021173" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0008707" }, { "agency": "European Research Council (ERC)", "grant_number": "864234" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "390776260" }, { "agency": "National Research Foundation of Korea", "grant_number": "2019M1A2A2065612" }, { "agency": "National Research Foundation of Korea", "grant_number": "2018R1A2A1A05077909" }, { "agency": "Japan Society for the Promotion of Science (JSPS)", "grant_number": "JP20H00396" }, { "agency": "Japan Society for the Promotion of Science (JSPS)", "grant_number": "JP17H06440" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "191299" }, { "agency": "Biotechnology and Biological Sciences Research Council (BBSRC)", "grant_number": "BB/R018413/1" }, { "agency": "European Research Council (ERC)", "grant_number": "819580" }, { "agency": "University of Tokyo", "grant_number": "MbSC2030" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-17-EURE-0003" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-18-CE05-0017-05" }, { "agency": "European Research Council (ERC)", "grant_number": "883264" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" }, { "agency": "Ministry of Economic Affairs and Climate Policy (Netherlands)" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "406944504" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "JCAP" } ] }, "doi": "10.1088/1361-6463/ac6f97", "primary_object": { "basename": "Segev_2022_J._Phys._D__Appl._Phys._55_323003.pdf", "url": "https://authors.library.caltech.edu/records/83tv1-p3k51/files/Segev_2022_J._Phys._D__Appl._Phys._55_323003.pdf" }, "pub_year": "2022", "author_list": "Segev, Gideon; Kibsgaard, Jakob; et el." }, { "id": "https://authors.library.caltech.edu/records/ckqjx-89a34", "eprint_id": 115030, "eprint_status": "archive", "datestamp": "2023-08-22 16:18:14", "lastmod": "2023-10-24 15:17:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Young-James-L", "name": { "family": "Young", "given": "James L." } }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Byrne-Sean-T", "name": { "family": "Byrne", "given": "Sean T." }, "orcid": "0000-0002-5466-3112" }, { "id": "Steiner-Myles-A", "name": { "family": "Steiner", "given": "Myles A." }, "orcid": "0000-0003-1643-9766" }, { "id": "Deutsch-Todd-G", "name": { "family": "Deutsch", "given": "Todd G." }, "orcid": "0000-0001-6577-1226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Failure Modes of Platinized pn\u207a-GaInP Photocathodes for Solar-Driven H\u2082 Evolution", "ispublished": "pub", "full_text_status": "public", "keywords": "photoelectrochemistry; III\u2212V semiconductor; water splitting; failure mode; solar fuels; General Materials Science", "note": "\u00a9 2022 American Chemical Society. \n\nReceived 29 January 2022. Accepted 13 May 2022. Published online 6 June 2022. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and by award DE-SC0022087 from the DOE Office of Basic Energy Sciences. Research was in part carried out at the Molecular Materials Research Center (MMRC) of the Beckman Institute of the California Institute of Technology. Dr. Nathan Dalleska is thanked for assistance with ICP-MS analysis. The authors from NREL acknowledge research support from the HydroGEN Advanced Water Splitting Materials Consortium, established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under Award Number DE-EE-0008084. This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy under Contract Number DE-AC36-08GO28308. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. Jake Evans is thanked for assistance with experiments. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - am2c01845_si_001.pdf
", "abstract": "The long-term stability for the hydrogen-evolution reaction (HER) of homojunction pn\u207a-Ga_(0.52)In_(0.48)P photocathodes (band gap = 1.8 eV) with an electrodeposited Pt catalyst (pn\u207a-GaInP/Pt) has been systematically evaluated in both acidic and alkaline electrolytes. Electrode dissolution during chronoamperometry was correlated with changes over time in the current density-potential (J\u2013E) behavior to reveal the underlying failure mechanism. Pristine pn\u207a-GaInP/Pt photocathodes yielded an open-circuit photopotential (Eoc) as positive as >1.0 V vs the potential of the reversible hydrogen electrode (RHE) and a light-limited current density (J\u209a\u2095) of >12 mA cm\u207b\u00b2 (1-sun illumination). However, E\u2092\ua700 and J\u209a\u2095 gradually degraded at either pH 0 or pH 14. The performance degradation was attributed to three different failure modes: (1) gradual thinning of the n\u207a-emitter layer due to GaInP dissolution in acid; (2) active corrosion of the underlying GaAs substrate at positive potentials causing delamination of the upper GaInP epilayers; and (3) direct GaAs/electrolyte contact compromising the operational stability of the device. This work reveals the importance of both substrate stability and structural integrity of integrated photoelectrodes toward stable solar fuel generation.", "date": "2022-06-15", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "14", "number": "23", "publisher": "American Chemical Society", "pagerange": "26622-26630", "id_number": "CaltechAUTHORS:20220606-736144000", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220606-736144000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE-0008084" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.2c01845", "primary_object": { "basename": "am2c01845_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ckqjx-89a34/files/am2c01845_si_001.pdf" }, "pub_year": "2022", "author_list": "Yu, Weilai; Buabthong, Pakpoom; et el." }, { "id": "https://authors.library.caltech.edu/records/fsknh-f7q63", "eprint_id": 115044, "eprint_status": "archive", "datestamp": "2023-08-22 15:57:29", "lastmod": "2023-10-24 15:17:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" }, "orcid": "0000-0002-2955-9671" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan" }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Numerical Simulation and Modeling of Hydrogen Gas Evolution on Planar and Microwire Array Electrodes", "ispublished": "pub", "full_text_status": "public", "keywords": "Materials Chemistry; Electrochemistry; Surfaces, Coatings and Films; Condensed Matter Physics; Renewable Energy, Sustainability and the Environment; Electronic, Optical and Magnetic Materials", "note": "\u00a9 2022 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. \n\nReceived 4 February 2022. Revised 24 May 2022. Accepted 31 May 2022. Accepted Manuscript online 1 June 2022. \n\nThis work was supported in part by the U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award number DE-SC0022087. This work was also supported in part by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award number DE-SC0004993. We are grateful to participate in this special issue to acknowledge on his 100th birthday the seminal contributions and extraordinary collegiality of Prof John Goodenough over decades of inspirational service to electrochemical societies, research, technology and electrochemists.\n\nPublished - Chen_2022_J._Electrochem._Soc._169_066510.pdf
Accepted Version - Chen+et+al_2022_J._Electrochem._Soc._10.1149_1945-7111_ac751e.pdf
Supplemental Material - jesac751esupp1.pdf
", "abstract": "The impact of gas evolution on the electrochemical characteristics of planar electrodes and microwire array electrodes has been analyzed using modeling and simulation. The impacts can mainly be broken into three phenomena: a) a shift in the local reversible hydrogen electrode potential; b) hyperpolarization; and c) an increase in the solution resistance of the electrolyte. The local reversible hydrogen electrode potential shift was found to play the most important role, constituting >40% of the total potential drop between the cathode and reference electrode, following correction for cell resistance. Compared to planar electrodes, a microwire array structure reduces the impact of bubbles on the solution conductance, but the shift in the local reversible hydrogen electrode potential varies with distance from the actual electrode surface.", "date": "2022-06", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "169", "number": "6", "publisher": "Electrochemical Society", "pagerange": "Art. No. 066510", "id_number": "CaltechAUTHORS:20220606-736390000", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220606-736390000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/1945-7111/ac751e", "primary_object": { "basename": "Chen+et+al_2022_J._Electrochem._Soc._10.1149_1945-7111_ac751e.pdf", "url": "https://authors.library.caltech.edu/records/fsknh-f7q63/files/Chen+et+al_2022_J._Electrochem._Soc._10.1149_1945-7111_ac751e.pdf" }, "related_objects": [ { "basename": "Chen_2022_J._Electrochem._Soc._169_066510.pdf", "url": "https://authors.library.caltech.edu/records/fsknh-f7q63/files/Chen_2022_J._Electrochem._Soc._169_066510.pdf" }, { "basename": "jesac751esupp1.pdf", "url": "https://authors.library.caltech.edu/records/fsknh-f7q63/files/jesac751esupp1.pdf" } ], "pub_year": "2022", "author_list": "Chen, Yikai and Lewis, Nathan" }, { "id": "https://authors.library.caltech.edu/records/380cm-fw777", "eprint_id": 109890, "eprint_status": "archive", "datestamp": "2023-08-22 15:05:53", "lastmod": "2023-10-23 18:12:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chang-Benjamin-K", "name": { "family": "Chang", "given": "Benjamin K." }, "orcid": "0000-0003-1304-9324" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Lee-Nien-En", "name": { "family": "Lee", "given": "Nien-En" }, "orcid": "0000-0002-3172-7750" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Intermediate polaronic charge transport in organic crystals from a many-body first-principles approach", "ispublished": "pub", "full_text_status": "public", "keywords": "Computational methods; Molecular electronics; Physical chemistry; Semiconductors", "note": "\u00a9 2022 The Author(s). Published in partnership with the Shanghai Institute of Ceramics of the Chinese Academy of Sciences. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 13 January 2022; Accepted 24 February 2022; Published 11 April 2022. \n\nThis work was supported by the National Science Foundation under Grant No. DMR-1750613. J.-J.Z. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of some computational methods employed in this work was supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. N.-E.L. was supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant FA9550-18-1-0280. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231. \n\nData availability: The data supporting the findings of this study, and in particular the files for the electron-phonon and BTE calculations, are available on Materials Cloud Archive with the identifier doi:10.24435/materialscloud:6t-e0. The authors are available to provide additional data and information upon reasonable request. \n\nCode availability: The PERTURBO code used in this work is an open source software, and can be downloaded at https://perturbo-code.github.io. The BTE subroutines are included in the current release, and the CK subroutines will be included in a future release. \n\nContributions: B.K.C. and M.B. conceived and designed the research. B.K.C. performed calculation and analysis. J.-J.Z. and N.-E.L. provided technical and theoretical support. M.B. supervised the entire research project. All authors discussed the results and contributed to the manuscript. \n\nThe authors declare no competing interests.\n\nPublished - s41524-022-00742-6.pdf
Submitted - 2106.09810.pdf
Supplemental Material - 41524_2022_742_MOESM1_ESM.pdf
", "abstract": "Charge transport in organic molecular crystals (OMCs) is conventionally categorized into two limiting regimes\u2009\u2212\u2009band transport, characterized by weak electron-phonon (e-ph) interactions, and charge hopping due to localized polarons formed by strong e-ph interactions. However, between these two limiting cases there is a less well understood intermediate regime where polarons are present but transport does not occur via hopping. Here we show a many-body first-principles approach that can accurately predict the carrier mobility in this intermediate regime and shed light on its microscopic origin. Our approach combines a finite-temperature cumulant method to describe strong e-ph interactions with Green-Kubo transport calculations. We apply this parameter-free framework to naphthalene crystal, demonstrating electron mobility predictions within a factor of 1.5\u22122 of experiment between 100 and 300\u2009K. Our analysis reveals the formation of a broad polaron satellite peak in the electron spectral function and the failure of the Boltzmann equation in the intermediate regime.", "date": "2022-04-11", "date_type": "published", "publication": "npj Computational Materials", "volume": "8", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 63", "id_number": "CaltechAUTHORS:20210716-222534684", "issn": "2057-3960", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210716-222534684", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41524-022-00742-6", "primary_object": { "basename": "s41524-022-00742-6.pdf", "url": "https://authors.library.caltech.edu/records/380cm-fw777/files/s41524-022-00742-6.pdf" }, "related_objects": [ { "basename": "2106.09810.pdf", "url": "https://authors.library.caltech.edu/records/380cm-fw777/files/2106.09810.pdf" }, { "basename": "41524_2022_742_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/380cm-fw777/files/41524_2022_742_MOESM1_ESM.pdf" } ], "pub_year": "2022", "author_list": "Chang, Benjamin K.; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/vkzge-cnn07", "eprint_id": 113517, "eprint_status": "archive", "datestamp": "2023-08-22 14:02:59", "lastmod": "2023-10-23 19:11:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kong-Shufeng", "name": { "family": "Kong", "given": "Shufeng" }, "orcid": "0000-0003-4264-3330" }, { "id": "Ricci-Francesco", "name": { "family": "Ricci", "given": "Francesco" } }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Density of states prediction for materials discovery via contrastive learning from probabilistic embeddings", "ispublished": "pub", "full_text_status": "public", "keywords": "Computational methods; Computer science; Thermoelectrics; General Physics and Astronomy; General Biochemistry, Genetics and Molecular Biology; General Chemistry", "note": "\u00a9 The Author(s) 2022. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 08 October 2021; Accepted 26 January 2022; Published 17 February 2022. \n\nThis work was funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0020383 (design of prediction task, development of use case, validation of predicted materials, model evaluation; grant received by J.N., C.G., and J.G.) and by the Toyota Research Institute through the Accelerated Materials Design and Discovery program (development of machine learning models; grant received by C.G. and J.G.). \n\nData availability: The input data as well as the predicted phDOS and eDOS data generated in this study have been deposited in the CaltechData database under accession code 8975 and https://doi.org/10.22002/D1.8975, and are available at https://data.caltech.edu/records/8975and https://www.cs.cornell.edu/gomes/udiscoverit/?tag=materials. \n\nCode availability: Source code for Mat2Spec62 is available from https://github.com/gomes-lab/Mat2Spec(https://doi.org/10.5281/zenodo.5863471) and from https://www.cs.cornell.edu/gomes/udiscoverit/?tag=materials. \n\nAuthor Contributions: These authors contributed equally: Shufeng Kong, Francesco Ricci. \n\nS.K. designed and implemented Mat2Spec with guidance from C.G., F.R., D.G., J.N., and J.G. designed the use case. F.R. performed DFT calculations and interpreted results. S.K., F.R., D.G., and J.G. wrote the manuscript with contributions from all authors. J.N., C.G., and J.G. conceived the project and supervised the work. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Pierre-Paul De Breuck, Logan Ward, and the other, anonymous, reviewer for their contribution to the peer review of this work. Peer reviewer reports are available.\n\nPublished - s41467-022-28543-x.pdf
Accepted Version - 2110.11444.pdf
Supplemental Material - 41467_2022_28543_MOESM1_ESM.pdf
Supplemental Material - 41467_2022_28543_MOESM2_ESM.pdf
", "abstract": "Machine learning for materials discovery has largely focused on predicting an individual scalar rather than multiple related properties, where spectral properties are an important example. Fundamental spectral properties include the phonon density of states (phDOS) and the electronic density of states (eDOS), which individually or collectively are the origins of a breadth of materials observables and functions. Building upon the success of graph attention networks for encoding crystalline materials, we introduce a probabilistic embedding generator specifically tailored to the prediction of spectral properties. Coupled with supervised contrastive learning, our materials-to-spectrum (Mat2Spec) model outperforms state-of-the-art methods for predicting ab initio phDOS and eDOS for crystalline materials. We demonstrate Mat2Spec's ability to identify eDOS gaps below the Fermi energy, validating predictions with ab initio calculations and thereby discovering candidate thermoelectrics and transparent conductors. Mat2Spec is an exemplar framework for predicting spectral properties of materials via strategically incorporated machine learning techniques.", "date": "2022-02-17", "date_type": "published", "publication": "Nature Communications", "volume": "13", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 949", "id_number": "CaltechAUTHORS:20220222-762467100", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220222-762467100", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" }, { "agency": "Toyota Research Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-022-28543-x", "primary_object": { "basename": "2110.11444.pdf", "url": "https://authors.library.caltech.edu/records/vkzge-cnn07/files/2110.11444.pdf" }, "related_objects": [ { "basename": "41467_2022_28543_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/vkzge-cnn07/files/41467_2022_28543_MOESM1_ESM.pdf" }, { "basename": "41467_2022_28543_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/vkzge-cnn07/files/41467_2022_28543_MOESM2_ESM.pdf" }, { "basename": "s41467-022-28543-x.pdf", "url": "https://authors.library.caltech.edu/records/vkzge-cnn07/files/s41467-022-28543-x.pdf" } ], "pub_year": "2022", "author_list": "Kong, Shufeng; Ricci, Francesco; et el." }, { "id": "https://authors.library.caltech.edu/records/mpbsk-n1m29", "eprint_id": 112091, "eprint_status": "archive", "datestamp": "2023-08-22 13:22:29", "lastmod": "2023-10-23 20:53:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lamaison-Sarah", "name": { "family": "Lamaison", "given": "Sarah" } }, { "id": "Wakerley-David", "name": { "family": "Wakerley", "given": "David" } }, { "id": "Kracke-Frauke", "name": { "family": "Kracke", "given": "Frauke" } }, { "id": "Moore-Thomas", "name": { "family": "Moore", "given": "Thomas" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" } }, { "id": "Lee-Dong-Un", "name": { "family": "Lee", "given": "Dong Un" }, "orcid": "0000-0001-7591-5350" }, { "id": "Wang-Lei", "name": { "family": "Wang", "given": "Lei" } }, { "id": "Hubert-McKenzie-A", "name": { "family": "Hubert", "given": "McKenzie A." }, "orcid": "0000-0002-9987-0748" }, { "id": "Aviles-Acosta-Jaime-E", "name": { "family": "Aviles Acosta", "given": "Jaime E." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Duoss-Eric-B", "name": { "family": "Duoss", "given": "Eric B." } }, { "id": "Baker-Sarah", "name": { "family": "Baker", "given": "Sarah" } }, { "id": "Beck-Victor-A", "name": { "family": "Beck", "given": "Victor A." }, "orcid": "0000-0002-0625-9545" }, { "id": "Spormann-Alfred-M", "name": { "family": "Spormann", "given": "Alfred M." }, "orcid": "0000-0001-5103-9704" }, { "id": "Fontecave-Marc", "name": { "family": "Fontecave", "given": "Marc" } }, { "id": "Hahn-Christopher", "name": { "family": "Hahn", "given": "Christopher" } }, { "id": "Jaramillo-Thomas-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "Designing a Zn\u2013Ag Catalyst Matrix and Electrolyzer System for CO\u2082 Conversion to CO and Beyond", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon dioxide conversion; carbon monoxide; gas diffusion electrodes; mass activities; membrane electrode assemblies; microbial coupling; multiphysics models; Mechanical Engineering; Mechanics of Materials; General Materials Science", "note": "\u00a9 2021 Wiley-VCH GmbH. \n\nIssue Online: 07 January 2022; Version of Record online: 21 October 2021; Manuscript revised: 24 July 2021; Manuscript received: 25 May 2021. \n\nS.L. and D.W. contributed equally to this work. This research was supported by a cooperative research and development agreement with TOTAL American Services, Inc. (affiliate of TOTAL SE, France) and Department of Energy under agreement number TC02307. T.M., E.B.D., S.B., and V.B. contributed under the auspices of the US Department of Energy under Contract DE-AC52-07-NA27344 and were supported by the LLNL-LDRD program under project number 19-SI-005, LLNL Release Number LLNL-JRNL-817428. The synthesis and composition characterization of sputtered thin film electrodes carried out by L.Z. and J.M.G. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. F.K. and A.S. were supported by the Global Climate and Energy Project. S.L. was funded by the Corps des Ponts, des Eaux et des For\u00eats (Division of the French Ministry of Ecological Transition). D.W. was supported by a Lindemann Trust Fellowship (English-Speaking Union, UK). The authors acknowledge assistance from Juliet Jamtgaard for assistance in acquiring XPS samples and Guangchao Li for carrying out ICP measurements. The authors would also like to thank Dr. Alessandro Gallo and Dr. Joel Sanchez for fruitful spectroscopy discussions. \n\nThe authors declare no conflict of interest. \n\nData Availability Statement: The data that supports the findings of this study are available in the Supporting Information of this article, and from the corresponding author upon reasonable request.\n\nSupplemental Material - adma202103963-sup-0001-suppmat.pdf
", "abstract": "CO\u2082 emissions can be transformed into high-added-value commodities through CO\u2082 electrocatalysis; however, efficient low-cost electrocatalysts are needed for global scale-up. Inspired by other emerging technologies, the authors report the development of a gas diffusion electrode containing highly dispersed Ag sites in a low-cost Zn matrix. This catalyst shows unprecedented Ag mass activity for CO production: \u2212614 mA cm\u207b\u00b2 at 0.17 mg of Ag. Subsequent electrolyte engineering demonstrates that halide anions can further improve stability and activity of the Zn\u2013Ag catalyst, outperforming pure Ag and Au. Membrane electrode assemblies are constructed and coupled to a microbial process that converts the CO to acetate and ethanol. Combined, these concepts present pathways to design catalysts and systems for CO\u2082 conversion toward sought-after products.", "date": "2022-01-06", "date_type": "published", "publication": "Advanced Materials", "volume": "34", "number": "1", "publisher": "Wiley", "pagerange": "Art. No. 2103963", "id_number": "CaltechAUTHORS:20211130-202117453", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211130-202117453", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "TOTAL American Services, Inc." }, { "agency": "Department of Energy (DOE)", "grant_number": "TC02307" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC52-07-NA27344" }, { "agency": "Lawrence Livermore National Laboratory", "grant_number": "19-SI-005" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Global Climate and Energy Project (GCEP)" }, { "agency": "Ministry of Ecological Transition (France)" }, { "agency": "Lindemann Trust Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/adma.202103963", "primary_object": { "basename": "adma202103963-sup-0001-suppmat.pdf", "url": "https://authors.library.caltech.edu/records/mpbsk-n1m29/files/adma202103963-sup-0001-suppmat.pdf" }, "pub_year": "2022", "author_list": "Lamaison, Sarah; Wakerley, David; et el." }, { "id": "https://authors.library.caltech.edu/records/2h146-mr664", "eprint_id": 112325, "eprint_status": "archive", "datestamp": "2023-09-22 22:34:56", "lastmod": "2023-10-23 23:23:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary Philip" }, "orcid": "0000-0003-2538-0794" }, { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Catalytic open-circuit passivation by thin metal oxide films of p-Si anodes in aqueous alkaline electrolytes", "ispublished": "pub", "full_text_status": "public", "keywords": "Pollution; Nuclear Energy and Engineering; Renewable Energy, Sustainability and the Environment; Environmental Chemistry", "note": "\u00a9 The Royal Society of Chemistry 2022. \n\nSubmitted 28 Sep 2021. Accepted 26 Nov 2021. First published 29 Nov 2021. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award number DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. Research was in part performed at the Molecular Materials Resource Center of the Beckman Institute.\n\nSupplemental Material - d1ee03040j1.pdf__ga=2.248598279.1627782830.1639070284-494341399.1632163545
", "abstract": "Ni and NiO\u2093-based protective thin films are shown to catalyze the oxidation of Si in the presence of O\u2082 in strongly alkaline KOH(aq) even in the absence of illumination. The O\u2082 in solution drove the open-circuit potential of the electrode to >0.4 V, which is positive of the Si passivation potential. The elevated electrochemical potential of the surface promoted formation of passive oxides on exposed Si regions of Si/Ni electrodes. Catalytic passivation of Si extended the durability of an np\u207a-Si(100)/NiO\u2093 photoanode to >400 h while operating under simulated day/night cycles. In contrast, electrodes without a Ni(O\u2093) layer and/or without O\u2082 in solution displayed direct etching of the Si and corrosion pitting during non-illuminated, simulated nighttime episodes of day/night cycling. The O\u2082-derived catalyzed passivation of Si using thin films can be generalized to multiple phases of NiO\u2093 as well as to materials other than Ni. Relative to operation in aqueous alkaline conditions, decreasing the pH of the electrolyte decreased the dissolution rate of the protective oxide layer formed by the catalyzed passivation process, and consequently increased the durability of the photoanode, but yielded lower photoelectrode fill factors for water oxidation due to the relatively large kinetic overpotentials for the electrocatalyzed oxygen-evolution reaction at near-neutral pH.", "date": "2022-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "15", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "334-345", "id_number": "CaltechAUTHORS:20211209-456392000", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211209-456392000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d1ee03040j", "primary_object": { "basename": "d1ee03040j1.pdf", "url": "https://authors.library.caltech.edu/records/2h146-mr664/files/d1ee03040j1.pdf" }, "pub_year": "2022", "author_list": "Fu, Harold J.; Buabthong, Pakpoom; et el." }, { "id": "https://authors.library.caltech.edu/records/g72fr-qzy96", "eprint_id": 112063, "eprint_status": "archive", "datestamp": "2023-08-22 12:44:34", "lastmod": "2023-10-23 20:52:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Young-James-L", "name": { "family": "Young", "given": "James L." } }, { "id": "Deutsch-Todd-G", "name": { "family": "Deutsch", "given": "Todd G." }, "orcid": "0000-0001-6577-1226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Understanding the Stability of Etched or Platinized p-GaInP Photocathodes for Solar-Driven H\u2082 Evolution", "ispublished": "pub", "full_text_status": "public", "keywords": "photoelectrode; electrodeposition; semiconductor; hydrogen-evolution reaction; tandem solar-fuel generators; General Materials Science", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: September 23, 2021; Accepted: November 8, 2021; Published: November 25, 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. Research was in part performed at the Molecular Materials Research Center (MMRC) of the Beckman Institute of the California Institute of Technology. Dr. Nathan Dalleska is thanked for assistance with ICP\u2013MS analysis. Dr. Myles Steiner is thanked for assistance with material fabrication. The authors acknowledge research support from the HydroGEN Advanced Water Splitting Materials Consortium, established as part of the Energy Materials Network under the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Hydrogen and Fuel Cell Technologies Office, under Award Number DE-EE-0008084. This work was authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the U.S. Department of Energy under Contract Number DE-AC36-08GO28308. The views expressed in the article do not necessarily represent the views of the DOE or the U.S. Government. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for U.S. Government purposes. \\\n\nThe authors declare no competing financial interest.\n\nSupplemental Material - am1c18243_si_001.pdf
", "abstract": "The long-term stability in acidic or alkaline aqueous electrolytes of p-Ga_(0.52)In_(0.48)P photocathodes, with a band gap of \u223c1.8 eV, for the solar-driven hydrogen-evolution reaction (HER) has been evaluated from a thermodynamic, kinetic, and mechanistic perspective. At either pH 0 or pH 14, etched p-GaInP electrodes corroded cathodically under illumination and formed metallic In0 on the photoelectrode surface. In contrast, under the same conditions, electrodeposition of Pt facilitated the HER kinetics and stabilized p-GaInP/Pt photoelectrodes against such cathodic decomposition. When held at 0 V versus the reversible hydrogen electrode, p-GaInP/Pt electrodes in either pH = 0 or pH = 14 exhibited stable current densities (J) of \u223c\u22129 mA cm\u207b\u00b2 for hundreds of hours under simulated 1 sun illumination. During the stability tests, the current density\u2013potential (J\u2013E) characteristics of the p-GaInP/Pt photoelectrodes degraded due to pH-dependent changes in the surface chemistry of the photocathode. This work provides a fundamental understanding of the stability and corrosion mechanisms of p-GaInP photocathodes that constitute a promising top light absorber for tandem solar-fuel generators.", "date": "2021-12-08", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "13", "number": "48", "publisher": "American Chemical Society", "pagerange": "57350-57361", "id_number": "CaltechAUTHORS:20201129-123456789", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201129-123456789", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE-0008084" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.1c18243", "primary_object": { "basename": "am1c18243_si_001.pdf", "url": "https://authors.library.caltech.edu/records/g72fr-qzy96/files/am1c18243_si_001.pdf" }, "pub_year": "2021", "author_list": "Yu, Weilai; Young, James L.; et el." }, { "id": "https://authors.library.caltech.edu/records/bzms3-zmb46", "eprint_id": 111845, "eprint_status": "archive", "datestamp": "2023-08-22 11:58:56", "lastmod": "2023-10-23 17:49:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Truttmann-Tristan-K", "name": { "family": "Truttmann", "given": "Tristan K." }, "orcid": "0000-0003-3016-4340" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Lu-I-Te", "name": { "family": "Lu", "given": "I-Te" } }, { "id": "Rajapitamahuni-Anil-Kumar", "name": { "family": "Rajapitamahuni", "given": "Anil Kumar" } }, { "id": "Liu-Fengdeng", "name": { "family": "Liu", "given": "Fengdeng" } }, { "id": "Mates-Thomas-E", "name": { "family": "Mates", "given": "Thomas E." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" }, { "id": "Jalan-Bharat", "name": { "family": "Jalan", "given": "Bharat" }, "orcid": "0000-0002-7940-0490" } ] }, "title": "Combined experimental-theoretical study of electron mobility-limiting mechanisms in SrSnO\u2083", "ispublished": "pub", "full_text_status": "public", "keywords": "Electronic properties and materials; Semiconductors", "note": "\u00a9 The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 19 January 2021; Accepted 22 October 2021; Published 11 November 2021. \n\nThis work was supported by the Air Force Office of Scientific Research (AFOSR) through Grant Nos. FA9550-19-1-0245 and FA9550-21-1-0025. Part of this work was supported by the National Science Foundation through DMR-1741801 and partially by the UMN MRSEC program under Award No. DMR- 2011401. Parts of this work were carried out in the Characterization Facility, University of Minnesota, which receives partial support from NSF through the MRSEC program. Work at Caltech was supported as follows: J.-J.Z. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. M.B. and I.-T.L. were supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant FA9550-18-1-0280. \n\nData availability: The data that support the findings of this study are available in the manuscript or its Supplementary Information. Other data are available from the corresponding authors (T.K.T. or B.J.) upon reasonable request. \n\nCode availability: All code that was used to generate the findings of this study are available from the references within or otherwise are available from the authors upon reasonable request. \n\nAuthor Contributions: T.T. and F.L. grew and structurally characterized samples. T.T. and A.K.R. performed transport measurements, the data from which were analyzed and fit by T.T., A.K.R., I.-T.L, M.B., and B.J. The first-principles calculations were performed by J.-J.Z. and I.-T.L. under the supervision of M.B. SIMS measurements were performed by T.M. and were analyzed by T.M., T.T., and B.J. All authors discussed, interpreted the results, and prepared the manuscript. B.J. coordinated all aspects of the project. \n\nThe authors declare no competing interests. \n\nPeer review information: Communications Physics thanks the anonymous reviewers for their contribution to the peer review of this work.\n\nTruttmann, T.K., Zhou, JJ., Lu, IT. et al. Publisher Correction: Combined experimental-theoretical study of electron mobility-limiting mechanisms in SrSnO3. Commun Phys 5, 90 (2022). https://doi.org/10.1038/s42005-022-00868-5\n\nPublished - s42005-021-00742-w.pdf
Supplemental Material - 42005_2021_742_MOESM1_ESM.pdf
Erratum - s42005-022-00868-5.pdf
", "abstract": "The discovery and development of ultra-wide bandgap (UWBG) semiconductors is crucial to accelerate the adoption of renewable power sources. This necessitates an UWBG semiconductor that exhibits robust doping with high carrier mobility over a wide range of carrier concentrations. Here we demonstrate that epitaxial thin films of the perovskite oxide Nd_xSr_(1\u2212x)SnO\u2083 (SSO) do exactly this. Nd is used as a donor to successfully modulate the carrier concentration over nearly two orders of magnitude, from 3.7 \u00d7 10\u00b9\u2078 cm\u207b\u00b3 to 2.0 \u00d7 10\u00b2\u2070 cm\u207b\u00b3. Despite being grown on lattice-mismatched substrates and thus having relatively high structural disorder, SSO films exhibited the highest room-temperature mobility, ~70\u2009cm\u00b2\u2009V\u207b\u00b9\u2009s\u207b\u00b9, among all known UWBG semiconductors in the range of carrier concentrations studied. The phonon-limited mobility is calculated from first principles and supplemented with a model to treat ionized impurity and Kondo scattering. This produces excellent agreement with experiment over a wide range of temperatures and carrier concentrations, and predicts the room-temperature phonon-limited mobility to be 76\u201399 cm\u00b2\u2009V\u207b\u00b9\u2009s\u207b\u00b9 depending on carrier concentration. This work establishes a perovskite oxide as an emerging UWBG semiconductor candidate with potential for applications in power electronics.", "date": "2021-11-11", "date_type": "published", "publication": "Communications Physics", "volume": "4", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 241", "id_number": "CaltechAUTHORS:20211111-210019575", "issn": "2399-3650", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211111-210019575", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-19-1-0245" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-21-1-0025" }, { "agency": "NSF", "grant_number": "DMR-1741801" }, { "agency": "NSF", "grant_number": "DMR- 2011401" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s42005-021-00742-w", "primary_object": { "basename": "42005_2021_742_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/bzms3-zmb46/files/42005_2021_742_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s42005-021-00742-w.pdf", "url": "https://authors.library.caltech.edu/records/bzms3-zmb46/files/s42005-021-00742-w.pdf" }, { "basename": "s42005-022-00868-5.pdf", "url": "https://authors.library.caltech.edu/records/bzms3-zmb46/files/s42005-022-00868-5.pdf" } ], "pub_year": "2021", "author_list": "Truttmann, Tristan K.; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/2xpwh-x1m66", "eprint_id": 111916, "eprint_status": "archive", "datestamp": "2023-08-20 05:52:37", "lastmod": "2023-10-23 20:48:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Moreno-Hernandez-Ivan-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Simonoff-Ethan", "name": { "family": "Simonoff", "given": "Ethan" }, "orcid": "0000-0002-2156-8602" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Investigations of the stability of etched or platinized p-InP(100) photocathodes for solar-driven hydrogen evolution in acidic or alkaline aqueous electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2021. \n\nSubmitted 09 Sep 2021; Accepted 23 Sep 2021; First published 30 Sep 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. Research was in part carried out at the Molecular Materials Resource Center (MMRC) of the Beckman Institute of the California Institute of Technology. W. Yu and C. G. Read acknowledge the Resnick Sustainability Institute (RSI) at Caltech for fellowship support. I. A. Moreno-Hernandez acknowledges a National Science Foundation Graduate Research Fellowship (Grant No. DGE-1144469). Prof. Dr Hans-Joachim Lewerenz, Dr Ke Sun and Dr Chengxiang Xiang are gratefully acknowledged for inspiring discussions. Dr Kimberly M. Papadantonakis is thanked for assistance with manuscript editing. Dr Nathan Dalleska is thanked for assistance with ICP-MS analyses. Ryan Jones is acknowledged for assistance with the design of the compression cell. Sean Byrne and Heng Dong are acknowledged for assistance with experiments. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d1ee02809j1.pdf
", "abstract": "The stability of p-InP photocathodes performing the hydrogen-evolution reaction (HER) has been evaluated in contact with either 1.0 M H\u2082SO\u2084 (aq) or 1.0 M KOH(aq), with a focus on identifying corrosion mechanisms. Stability for the solar-driven HER was evaluated using p-InP electrodes that were either etched or coated with an electrodeposited Pt catalyst (p-InP/Pt). Variables such as trace O\u2082 were systematically controlled during the measurements. Changes in surface characteristics after exposure to electrochemical conditions as well as electrode dissolution processes were monitored using X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma mass spectrometry (ICP-MS). In either H\u2082SO\u2084 or KOH, etched p-InP photoelectrodes corroded cathodically under illumination, forming metallic In\u2070 at the electrode surface. In contrast, electrodeposition of Pt kinetically stabilized illuminated p-InP photocathodes in both H\u2082SO\u2084 and KOH by inhibiting the cathodic corrosion pathway. Notably, when held at 0 V vs. the reversible hydrogen electrode (RHE) in 1.0 M H\u2082SO\u2084 (aq), p-InP/Pt exhibited a stable current density (J) of \u223c\u221218 mA cm\u207b\u00b2 for >285 h under simulated 1 Sun illumination. The long-term current density vs. potential (J\u2013E) behavior at pH 0 and pH 14 of p-InP/Pt photocathodes correlated with changes in the surface chemistry as well as the dissolution of p-InP. In acidic media, the J\u2013E behavior of p-InP/Pt photocathodes remained nearly constant with time, but the surface of a p-InP/Pt electrodes gradually turned P-rich via a slow and continuous leaching of In ions. In alkaline electrolyte, the surface of p-InP/Pt electrodes was passivated by formation of an InO_x layer that exhibited negligible dissolution but led to a substantial degradation in the J\u2013E characteristics. Consequently, changes in the catalytic kinetics and surface stoichiometry are both important considerations for determining the corrosion chemistry and the long-term operational stability of InP photoelectrodes.", "date": "2021-11-01", "date_type": "published", "publication": "Energy & Environmental Science", "volume": "14", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "6007-6020", "id_number": "CaltechAUTHORS:20211117-163656680", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211117-163656680", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d1ee02809j", "primary_object": { "basename": "d1ee02809j1.pdf", "url": "https://authors.library.caltech.edu/records/2xpwh-x1m66/files/d1ee02809j1.pdf" }, "pub_year": "2021", "author_list": "Yu, Weilai; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/9dkp8-dt670", "eprint_id": 111310, "eprint_status": "archive", "datestamp": "2023-08-20 05:44:10", "lastmod": "2023-10-23 20:30:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Simonoff-Ethan", "name": { "family": "Simonoff", "given": "Ethan" }, "orcid": "0000-0002-2156-8602" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Investigations of the stability of GaAs for photoelectrochemical H\u2082 evolution in acidic or alkaline aqueous electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2021. \n\nSubmitted 17 May 2021. Accepted 22 Sep 2021. First published\t22 Sep 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and by award DE-SC0022087 from the DOE Office of Basic Energy Sciences. Research was in part performed in the Molecular Materials Resource Center (MMRC) of the Beckman Institute of the California Institute of Technology. Phil Jahelka and Dr Chengxiang Xiang are gratefully acknowledged for fruitful discussions. Dr Nathan Dalleska provided assistance with ICP-MS analysis and Dr Pakpoom Buabthong assisted with XPS analysis. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d1ta04145b1.pdf
", "abstract": "The long-term stability of p-GaAs photocathodes has been investigated for the hydrogen-evolution reaction (HER) in contact with either 1.0 M H\u2082SO\u2084(aq) or 1.0 M KOH(aq). Stability for the HER was evaluated using p-GaAs electrodes that were either etched or coated with active HER catalysts (Pt and CoP). Changes in surface characteristics of GaAs after exposure to electrochemical conditions were monitored by X-ray photoelectron spectroscopy (XPS), and electrode dissolution processes were evaluated by inductively coupled plasma mass spectrometry (ICP-MS). Consistent with thermodynamic predictions, after operation of the HER at pH 0 or pH 14, illuminated etched p-GaAs electrodes exhibited minimal dissolution while preserving a nearly stoichiometric surface. Electrodeposition or sputtering of Pt on the p-GaAs surface promoted the formation of excess As\u2070 via an interfacial reaction during the HER. The resulting non-stoichiometric As\u2070-rich surface of p-GaAs/Pt electrodes caused a loss in photoactivity as well as substantial cathodic dark current. In contrast, p-GaAs electrodes coated with thin-film CoP catalysts did not display an increase in surficial As\u2070 after operation of the HER in acidic electrolytes. Minimization of deleterious interfacial reactions is thus critical to obtain extended stability in conjunction with high performance from p-GaAs photocathodes.", "date": "2021-10-28", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "9", "number": "40", "publisher": "Royal Society of Chemistry", "pagerange": "22958-22972", "id_number": "CaltechAUTHORS:20211008-224606577", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211008-224606577", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d1ta04145b", "primary_object": { "basename": "d1ta04145b1.pdf", "url": "https://authors.library.caltech.edu/records/9dkp8-dt670/files/d1ta04145b1.pdf" }, "pub_year": "2021", "author_list": "Yu, Weilai; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/6mc22-s2d96", "eprint_id": 111322, "eprint_status": "archive", "datestamp": "2023-08-20 05:33:08", "lastmod": "2023-10-23 20:31:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Rinaldi-Katherine-Z", "name": { "family": "Rinaldi", "given": "Katherine Z." }, "orcid": "0000-0002-0746-2852" }, { "id": "Kennedy-Kathleen-M", "name": { "family": "Kennedy", "given": "Kathleen M." }, "orcid": "0000-0002-7125-4871" }, { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Kuo-Tai-Jung", "name": { "family": "Kuo", "given": "Tai-Jung" } }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "GaAs Microisland Anodes Protected by Amorphous TiO\u2082 Films Mitigate Corrosion Spreading During Water Oxidation in Alkaline Electrolytes", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrochemistry, Layers, Electrodes, Defects, Gallium arsenide", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 7 June 2021. Accepted 20 September 2021. Published online 27 September 2021. Published in issue 8 October 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and under award DE-SC0022087 from the Basic Energy Sciences Office of the DOE. We gratefully acknowledge a gift from the Lam Research Unlock Ideas program. P.B. is grateful to Toy Jatuporn Leksut for assistance with illustrations and visualization of the data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz1c01174_si_001.pdf
", "abstract": "Microisland structures of \u223c200 \u03bcm diameter GaAs circles were fabricated and used to spatially isolate defects during electrochemical operation as an anode in aqueous alkaline electrolytes. The microisland structures allowed one to measure the rate and distribution of the pinhole formation on electrodes protected by 110 nm-thick amorphous titanium dioxide (a-TiO\u2082) films formed by atomic layer deposition. Although no crystalline regions were detected by Raman spectroscopy, a limited number of defects were present in the a-TiO2 layer and developed into new microscopic pinholes within the first 20 h of electrochemical operation. The film dissolved at a rate of <13 nm per day, and hence, intrinsic film dissolution was not the primary mode of pinhole formation during this first 20 h of operation. The fabrication processes presented herein only utilized chemical etching and mechanical polishing and, consequently, should be readily transferable to the fabrication of the more complicated np\u207a-GaAs structures.", "date": "2021-10-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "6", "number": "10", "publisher": "American Chemical Society", "pagerange": "3709-3714", "id_number": "CaltechAUTHORS:20211008-224620533", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20211008-224620533", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0022087" }, { "agency": "Lam Research Unlock Ideas" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.1c01174", "primary_object": { "basename": "nz1c01174_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6mc22-s2d96/files/nz1c01174_si_001.pdf" }, "pub_year": "2021", "author_list": "Buabthong, Pakpoom; Evans, Jake M.; et el." }, { "id": "https://authors.library.caltech.edu/records/ms7mx-66z24", "eprint_id": 110953, "eprint_status": "archive", "datestamp": "2023-08-20 05:32:50", "lastmod": "2023-10-23 19:57:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yadegari-Hossein", "name": { "family": "Yadegari", "given": "Hossein" }, "orcid": "0000-0002-2572-182X" }, { "id": "Ozden-Adnan", "name": { "family": "Ozden", "given": "Adnan" }, "orcid": "0000-0002-6924-1967" }, { "id": "Alkayyali-Tartela", "name": { "family": "Alkayyali", "given": "Tartela" }, "orcid": "0000-0003-3895-8700" }, { "id": "Soni-Vikram", "name": { "family": "Soni", "given": "Vikram" }, "orcid": "0000-0001-9354-475X" }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Sargent-Edward-H", "name": { "family": "Sargent", "given": "Edward H." }, "orcid": "0000-0003-0396-6495" }, { "id": "Sinton-David", "name": { "family": "Sinton", "given": "David" }, "orcid": "0000-0003-2714-6408" } ] }, "title": "Glycerol Oxidation Pairs with Carbon Monoxide Reduction for Low-Voltage Generation of C\u2082 and C\u2083 Product Streams", "ispublished": "pub", "full_text_status": "public", "keywords": "Oxides, Alcohols, Electrodes, Inorganic carbon compounds, Electrical energy", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: August 4, 2021; Published: September 14, 2021. \n\nThe authors acknowledge Ontario Centre for the Characterization of Advanced Materials (OCCAM) for sample preparation and characterization facilities. The authors acknowledge financial support from the Ontario Research Foundation: Research Excellence Program; the Natural Sciences and Engineering Research Council (NSERC) of Canada; the CIFAR Bio-Inspired Solar Energy program; and the Joint Centre of Artificial Synthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. D.S. acknowledges the NSERC E.W.R Steacie Memorial Fellowship. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). Infrastructure support from the Canada Foundation for Innovation and the Ontario Research Fund are also gratefully acknowledged. \n\nAuthor Contributions: D.S. and E.S. supervised the project. H.Y., D.S., and A.O. conceived the idea and designed the experiments. H.Y. carried out the experiments, collected and analyzed the data, and wrote the manuscript. A.O. aided with electrochemical measurements and analytical characterizations. T.A. performed the COMSOL modeling. All authors discussed the results and contributed to manuscript editing. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz1c01639_si_001.pdf
", "abstract": "Electrochemical carbon dioxide reduction to multicarbon products provides the storage of renewable energy in the form of chemical bonds, as well as a means to displace fossil sources of chemical feedstocks. However, the accompanying anodic oxygen evolution reaction (OER) reduces the energy efficiency of the process without providing a salable product. Replacing OER with alternative organic oxidation reactions (OORs) is an emerging strategy to reduce the full-cell potential and generate valuable products on both sides of the cell. We pursue carbon monoxide reduction that avoids carbonate formation and benefits from highly alkaline anode conditions favorable for OOR. This coelectrolysis strategy achieves a cathodic C\u2082\u208a product stream (71% FE) and an anodic C\u2083 product stream (75% FE) at 180 mA cm\u207b\u00b2 with a full-cell potential of 1.34 V. The integrated system reduces the CO-to-C\u2082H\u2084 energy requirement by 55% (to \u223c72 GJ/ton_(C\u2082H\u2084)), halving the projected energy cost of ethylene production from CO\u2082.", "date": "2021-10-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "6", "number": "10", "publisher": "American Chemical Society", "pagerange": "3538-3544", "id_number": "CaltechAUTHORS:20210917-215618208", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210917-215618208", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ontario Research Foundation" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Ontario Research Fund" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.1c01639", "primary_object": { "basename": "nz1c01639_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ms7mx-66z24/files/nz1c01639_si_001.pdf" }, "pub_year": "2021", "author_list": "Yadegari, Hossein; Ozden, Adnan; et el." }, { "id": "https://authors.library.caltech.edu/records/yg7f8-61e53", "eprint_id": 110952, "eprint_status": "archive", "datestamp": "2023-08-22 11:29:10", "lastmod": "2023-10-23 19:57:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." }, "orcid": "0000-0002-9210-344X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Dramatic Change in the Step Edges of the Cu(100) Electrocatalyst upon Exposure to CO: Operando Observations by Electrochemical STM and Explanation Using Quantum Mechanical Calculations", "ispublished": "pub", "full_text_status": "public", "keywords": "operando electrochemical STM; density functional theory; copper surface CO adsorption; step-edge reorientation", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: June 24, 2021; Published: September 14, 2021. \n\nThe invaluable contributions of Prof. Manuel P. Soriaga on the seriatim implementation of operando analytical protocols for CO\u2082 reduction studies are gratefully acknowledged. Manny passed away on July 17, 2019, and will always be missed in the electrochemical surface science community. The experimental portion of this paper is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. The computational studies are based on the work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award number DE-SC0021266. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under contract no. DE-AC02-05CH11231. \n\nAuthor Contributions: First authorship is equally shared by S.K., Y.-G.K., and J.H.B. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs1c02844_si_001.pdf
", "abstract": "Systematic structure\u2013activity correlations in the electrochemical surface science of CO\u2082 reduction (CO\u2082R) are typically anchored on low Miller-index (hkl) surfaces with characterization directed at the dominant well-defined basal planes. The present investigation focused on the visualization of the step edges of unreconstructed Cu(100), with and without CO dissolved in 0.1 M KOH, at the early onset-potential region of CO\u2082R. Operando electrochemical scanning tunneling microscopy revealed that the step-edge direction changed dramatically upon the adsorption\u2013desorption of CO at potentials of \u22121.0 to \u22120.8 V. Quantum mechanical calculations corroborated the favorable transformation of the step-edge direction from \u27e8110\u27e9 to \u27e8001\u27e9 as the pristine surface was decorated by CO.", "date": "2021-10-01", "date_type": "published", "publication": "ACS Catalysis", "volume": "11", "number": "19", "publisher": "American Chemical Society", "pagerange": "12068-12074", "id_number": "CaltechAUTHORS:20210917-215618128", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210917-215618128", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1493", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Liquid-Sunlight-Alliance" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.1c02844", "primary_object": { "basename": "cs1c02844_si_001.pdf", "url": "https://authors.library.caltech.edu/records/yg7f8-61e53/files/cs1c02844_si_001.pdf" }, "pub_year": "2021", "author_list": "Kwon, Soonho; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/k0tg0-d8t66", "eprint_id": 110945, "eprint_status": "archive", "datestamp": "2023-08-20 05:14:08", "lastmod": "2023-10-23 19:56:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Peterson-Elizabeth-A", "name": { "family": "Peterson", "given": "Elizabeth A." }, "orcid": "0000-0001-5379-3604" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "Aniketa A." }, "orcid": "0000-0003-2386-3848" }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Fackler-Sean-W", "name": { "family": "Fackler", "given": "Sean W." } }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Cooper-Jason-K", "name": { "family": "Cooper", "given": "Jason K." }, "orcid": "0000-0002-7953-4229" }, { "id": "Persson-Kristin-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Band Edge Energy Tuning through Electronic Character Hybridization in Ternary Metal Vanadates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 The Authors. Published by American Chemical Society. \n\nReceived: April 23, 2021; Revised: August 12, 2021; Published: September 13, 2021. \n\nThe band character calculations and band energy experiments were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US DOE (Award DE-SC0004993). Defect energy calculations and analysis of associated experimental data were supported by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. Research was in part carried out at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. This research used resources of the Advanced Light Source, a U.S. DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. We acknowledge computational resources provided by the National Energy Research Scientific Computing Center (NERSC), supported by the Office of Science of the Department of Energy under Award No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cm1c01415_si_001.pdf
", "abstract": "In the search for photoanode materials with band gaps suitable for utilization in solar fuel generation, approximately 1.2\u20132.8 eV, theory-guided experiments have identified a variety of materials that meet the band gap requirements and exhibit operational stability in harsh photoelectrochemical environments. In particular, M-V-O compounds (M is a transition metal or main group element) with VO\u2084 structural motifs were predicted to show a remarkably wide range of band energetics (>3 eV variation in the energy of valence band maximum) and characteristics, depending on the M and crystal structure, which is beyond the extent of electronic structured tuning observed in previously studied families of metal oxide photoanodes. While this finding guided experimental discovery of new photoanode materials, explicit experimental verification of the theoretical prediction of the tunable electronic structure of these materials has been lacking to date. In this study, we use X-ray photoelectron spectroscopy and Kelvin probe microscopy to experimentally investigate the electronic structure of M-V-O photoanodes, enabling comparison to theory on a common absolute energy scale. The results confirm the prediction that band edge energies of ternary vanadates vary significantly with metal cations. The valence band variation of approximately 1 eV observed here is larger than that reported in any analogous class of metal oxide semiconductors and demonstrates the promise of tuning the metal oxide electronic structure to enable efficient photoelectrocatalysis of the oxygen evolution reaction and beyond. Because midgap states can hamper realization of the high photovoltage sought by band edge tuning, we analyze the electronic contributions of oxygen vacancies for the representative photoanode V\u2084Cr\u2082O\u2081\u2083 to guide future research on the development of high-efficiency metal oxide photoanodes for solar fuel technology.", "date": "2021-09-28", "date_type": "published", "publication": "Chemistry of Materials", "volume": "33", "number": "18", "publisher": "American Chemical Society", "pagerange": "7242-7253", "id_number": "CaltechAUTHORS:20210917-215611668", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210917-215611668", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1021/acs.chemmater.1c01415", "primary_object": { "basename": "cm1c01415_si_001.pdf", "url": "https://authors.library.caltech.edu/records/k0tg0-d8t66/files/cm1c01415_si_001.pdf" }, "pub_year": "2021", "author_list": "Richter, Matthias H.; Peterson, Elizabeth A.; et el." }, { "id": "https://authors.library.caltech.edu/records/jjjjm-8d431", "eprint_id": 108510, "eprint_status": "archive", "datestamp": "2023-08-20 05:09:14", "lastmod": "2023-10-23 17:06:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" }, "orcid": "0000-0002-1763-5788" }, { "id": "Timrov-Iurii", "name": { "family": "Timrov", "given": "Iurii" }, "orcid": "0000-0002-6531-9966" }, { "id": "Floris-Andrea", "name": { "family": "Floris", "given": "Andrea" }, "orcid": "0000-0002-3160-6676" }, { "id": "Cococcioni-Matteo", "name": { "family": "Cococcioni", "given": "Matteo" }, "orcid": "0000-0002-1546-3513" }, { "id": "Marzari-Nicola", "name": { "family": "Marzari", "given": "Nicola" }, "orcid": "0000-0002-9764-0199" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Ab Initio Electron-Phonon Interactions in Correlated Electron Systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Physical Society. \n\nReceived 19 February 2021; accepted 12 August 2021; published 16 September 2021. \n\nWork at Caltech was supported by the National Science Foundation under Grant No. DMR-1750613. J.-J.\u2009Z. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DESC0004993. J.\u2009P. acknowledges support by the Korea Foundation for Advanced Studies. M.\u2009B. was partially supported by the Air Force Office of Scientific Research through the Young Investigator Program Grant No. FA955018-1-0280. M.\u2009C., I.\u2009T., and N.\u2009M. acknowledge support from the EU-H2020 NFFA (Grant Agreement No. 654360). I.\u2009T. and N.\u2009M. also acknowledge support by the Swiss National Science Foundation (SNSF), through Grant No. 200021-179138, and its National Centre of Competence in Research (NCCR) MARVEL.\u2009A.\u2009F. thanks the UK's HEC Materials Chemistry Consortium, funded by EPSRC (EP/L000202, EP/R029431). This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevLett.127.126404.pdf
Submitted - 2102.06840.pdf
Supplemental Material - Supplemental.pdf
", "abstract": "Electron-phonon (e\u2212ph) interactions are pervasive in condensed matter, governing phenomena such as transport, superconductivity, charge-density waves, polarons, and metal-insulator transitions. First-principles approaches enable accurate calculations of e\u2212ph interactions in a wide range of solids. However, they remain an open challenge in correlated electron systems (CES), where density functional theory often fails to describe the ground state. Therefore reliable e\u2212ph calculations remain out of reach for many transition metal oxides, high-temperature superconductors, Mott insulators, planetary materials, and multiferroics. Here we show first-principles calculations of e\u2212ph interactions in CES, using the framework of Hubbard-corrected density functional theory (DFT+U) and its linear response extension (DFPT+U), which can describe the electronic structure and lattice dynamics of many CES. We showcase the accuracy of this approach for a prototypical Mott system, CoO, carrying out a detailed investigation of its e\u2212ph interactions and electron spectral functions. While standard DFPT gives unphysically divergent and short-ranged e\u2212ph interactions, DFPT+U is shown to remove the divergences and properly account for the long-range Fr\u00f6hlich interaction, allowing us to model polaron effects in a Mott insulator. Our work establishes a broadly applicable and affordable approach for quantitative studies of e\u2212ph interactions in CES, a novel theoretical tool to interpret experiments in this broad class of materials.", "date": "2021-09-17", "date_type": "published", "publication": "Physical Review Letters", "volume": "127", "number": "12", "publisher": "American Physical Society", "pagerange": "Art. No. 126404", "id_number": "CaltechAUTHORS:20210322-123709144", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210322-123709144", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA955018-1-0280" }, { "agency": "European Research Council (ERC)", "grant_number": "654360" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "200021-179138" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/L000202" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/R029431" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevLett.127.126404", "primary_object": { "basename": "Supplemental.pdf", "url": "https://authors.library.caltech.edu/records/jjjjm-8d431/files/Supplemental.pdf" }, "related_objects": [ { "basename": "2102.06840.pdf", "url": "https://authors.library.caltech.edu/records/jjjjm-8d431/files/2102.06840.pdf" }, { "basename": "PhysRevLett.127.126404.pdf", "url": "https://authors.library.caltech.edu/records/jjjjm-8d431/files/PhysRevLett.127.126404.pdf" } ], "pub_year": "2021", "author_list": "Zhou, Jin-Jian; Park, Jinsoo; et el." }, { "id": "https://authors.library.caltech.edu/records/n4c8k-21638", "eprint_id": 110848, "eprint_status": "archive", "datestamp": "2023-08-22 11:14:03", "lastmod": "2023-10-23 19:54:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Lusann", "name": { "family": "Yang", "given": "Lusann" }, "orcid": "0000-0001-5071-2936" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Armstrong-Zan", "name": { "family": "Armstrong", "given": "Zan" } }, { "id": "Yang-Samuel-J", "name": { "family": "Yang", "given": "Samuel J." }, "orcid": "0000-0003-2460-6456" }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" } }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Roat-Christopher", "name": { "family": "Roat", "given": "Christopher" } }, { "id": "Wagner-Nicholas", "name": { "family": "Wagner", "given": "Nicholas" } }, { "id": "Coram-Marc", "name": { "family": "Coram", "given": "Marc" } }, { "id": "Berndl-Marc", "name": { "family": "Berndl", "given": "Marc" }, "orcid": "0000-0001-6750-5861" }, { "id": "Riley-Patrick", "name": { "family": "Riley", "given": "Patrick" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Discovery of complex oxides via automated experiments and data science", "ispublished": "pub", "full_text_status": "public", "keywords": "data science; materials discovery; complex oxides; optical absorption; oxygen evolution electrocatalysis", "note": "\u00a9 2021 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). \n\nEdited by Alexis T. Bell, University of California, Berkeley, CA, and approved August 2, 2021 (received for review April 16, 2021). \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a Department of Energy Energy Innovation Hub, supported through the US Department of Energy Office of Basic Energy Sciences under Award DE-SC0004993, which supported materials synthesis and characterization experiments. Google Applied Science supported the development and execution of the computational workflow as well as procurement of the hyperspectral microscope. Structural characterization and follow-up validation experiments were supported by the US Department of Energy Office of Basic Energy Sciences under Award DE-SC0020383. We are grateful for helpful discussions and guidance in the development of the computational workflow from Muskaan Goyal, Eric Christiansen, Edward A. Baltz, Derek Leong, Austin Blanco, and Mike Ando (Google Applied Science). We also appreciate the support of the experiment workflow from Edwin Soedarmadji (Caltech). We additionally appreciate helpful suggestions by David Fork and Michael Brenner (Google Applied Science). \n\nData Availability: The optical absorption spectra, fitted phase diagrams, and mixture probabilities have been deposited in Google Cloud Storage (http://storage.googleapis.com/gresearch/metal-oxide-spectroscopy/README.txt; see SI Appendix for documentation and access instructions). \n\nAuthor contributions: L.Y., J.A.H., M.B., P.R., and J.M.G. designed research; L.Y., J.A.H., K.K., L.Z., and M.H.R. performed research; L.Y., J.A.H., Z.A., S.J.Y., C.R., M.C., M.B., P.R., and J.M.G. contributed new reagents/analytic tools; L.Y., J.A.H., N.W., and J.M.G. analyzed data; and L.Y., J.A.H., and J.M.G. wrote the paper. \n\nCompeting interest statement: As listed in the affiliations, several authors are current or former employees of Google, a technology company that sells machine learning services as part of its business. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2106042118/-/DCSupplemental.\n\nPublished - e2106042118.full.pdf
Supplemental Material - pnas.2106042118.sapp.pdf
", "abstract": "The quest to identify materials with tailored properties is increasingly expanding into high-order composition spaces, with a corresponding combinatorial explosion in the number of candidate materials. A key challenge is to discover regions in composition space where materials have novel properties. Traditional predictive models for material properties are not accurate enough to guide the search. Herein, we use high-throughput measurements of optical properties to identify novel regions in three-cation metal oxide composition spaces by identifying compositions whose optical trends cannot be explained by simple phase mixtures. We screen 376,752 distinct compositions from 108 three-cation oxide systems based on the cation elements Mg, Fe, Co, Ni, Cu, Y, In, Sn, Ce, and Ta. Data models for candidate phase diagrams and three-cation compositions with emergent optical properties guide the discovery of materials with complex phase-dependent properties, as demonstrated by the discovery of a Co-Ta-Sn substitutional alloy oxide with tunable transparency, catalytic activity, and stability in strong acid electrolytes. These results required close coupling of data validation to experiment design to generate a reliable end-to-end high-throughput workflow for accelerating scientific discovery.", "date": "2021-09-14", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences", "volume": "118", "number": "37", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2106042118", "id_number": "CaltechAUTHORS:20210914-182227400", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210914-182227400", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Google Applied Science" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.2106042118", "pmcid": "PMC8449358", "primary_object": { "basename": "e2106042118.full.pdf", "url": "https://authors.library.caltech.edu/records/n4c8k-21638/files/e2106042118.full.pdf" }, "related_objects": [ { "basename": "pnas.2106042118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/n4c8k-21638/files/pnas.2106042118.sapp.pdf" } ], "pub_year": "2021", "author_list": "Yang, Lusann; Haber, Joel A.; et el." }, { "id": "https://authors.library.caltech.edu/records/hw471-n3745", "eprint_id": 110087, "eprint_status": "archive", "datestamp": "2023-08-22 11:07:32", "lastmod": "2023-10-23 18:17:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stach-Eric", "name": { "family": "Stach", "given": "Eric" } }, { "id": "DeCost-Brian", "name": { "family": "DeCost", "given": "Brian" } }, { "id": "Kusne-A-Gilad", "name": { "family": "Kusne", "given": "A. Gilad" } }, { "id": "Hattrick-Simpers-Jason", "name": { "family": "Hattrick-Simpers", "given": "Jason" } }, { "id": "Brown-Keith-A", "name": { "family": "Brown", "given": "Keith A." } }, { "id": "Reyes-Kristofer-G", "name": { "family": "Reyes", "given": "Kristofer G." } }, { "id": "Schrier-Joshua", "name": { "family": "Schrier", "given": "Joshua" } }, { "id": "Billinge-Simon", "name": { "family": "Billinge", "given": "Simon" } }, { "id": "Buonassisi-Tonio", "name": { "family": "Buonassisi", "given": "Tonio" } }, { "id": "Foster-Ian", "name": { "family": "Foster", "given": "Ian" } }, { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Mehta-Apurva", "name": { "family": "Mehta", "given": "Apurva" } }, { "id": "Montoya-Joseph", "name": { "family": "Montoya", "given": "Joseph" } }, { "id": "Olivetti-Elsa", "name": { "family": "Olivetti", "given": "Elsa" } }, { "id": "Park-Chiwoo", "name": { "family": "Park", "given": "Chiwoo" } }, { "id": "Rotenberg-Eli", "name": { "family": "Rotenberg", "given": "Eli" }, "orcid": "0000-0002-3979-8844" }, { "id": "Saikin-Semion-K", "name": { "family": "Saikin", "given": "Semion K." } }, { "id": "Smullin-Sylvia", "name": { "family": "Smullin", "given": "Sylvia" } }, { "id": "Stanev-Valentin", "name": { "family": "Stanev", "given": "Valentin" } }, { "id": "Maruyama-Benji", "name": { "family": "Maruyama", "given": "Benji" } } ] }, "title": "Autonomous experimentation systems for materials development: A community perspective", "ispublished": "pub", "full_text_status": "restricted", "keywords": "autonomy; artificial intelligence; machine learning; algorithmic development; research methods; human-machine teaming; workforce development; materials discovery; carbon nanotubes; additive manufacturing", "note": "\u00a9 2021 Published by Elsevier Inc. \n\nAvailable online 26 July 2021. \n\nThe authors gratefully acknowledge the contributions of the participants of the Autonomous Systems for Materials Development Workshop, held at the University of Pennsylvania Singh Center for Nanotechnology, 4\u20136 September, 2019, with support from the University of Pennsylvania, the Air Force Research Laboratory, Materials & Manufacturing Directorate, ACS Combinatorial Science, and the NSF through the University of Pennsylvania Materials Research Science and Engineering Center (MRSEC) (DMR-1720530). We also gratefully acknowledge John Russell of the Singh Center for his assistance in organizing this workshop. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. Support from the Air Force Research Laboratory Air Force Office of Scientific Research (AFOSR) LRIR no. 19RXCOR322 is gratefully acknowledged. K.A.B. acknowledges support from NSF CMMI-1661412. J.S. acknowledges support from the National Science Foundation (grant no. DMR-1928882), the Defense Advanced Research Projects Agency (contract no. HR001118C0036), and the Camille and Henry Dreyfus Foundation (TH-14-010). S.J.L.B. was supported by the U.S. National Science Foundation through grant DMREF-1922234. J.M.G. and C.P.G. acknowledge support from U.S. Department of Energy Office of Basic Energy Sciences under award DE-SC0020383. C.P. acknowledges support from AFOSR grant FA9550-18-1-0144. The authors acknowledge Lianne M.C. Beltran for professional editing. \n\nDeclaration of interests: S.K.S. is a founder of Kebotix, Inc. J.S. is a member of the scientific advisory board of Atinary Technologies, Inc. J.M.G. is a co-inventor on United States Patent Application 20200340941 related to the manuscript. \n\nData and code availability: ARES OS Software is available under the AFRL Open Source Software License at https://forms.gle/BetmdJtCAFwRLBiU6.", "abstract": "Solutions to many of the world's problems depend upon materials research and development. However, advanced materials can take decades to discover and decades more to fully deploy. Humans and robots have begun to partner to advance science and technology orders of magnitude faster than humans do today through the development and exploitation of closed-loop, autonomous experimentation systems. This review discusses the specific challenges and opportunities related to materials discovery and development that will emerge from this new paradigm. Our perspective incorporates input from stakeholders in academia, industry, government laboratories, and funding agencies. We outline the current status, barriers, and needed investments, culminating with a vision for the path forward. We intend the article to spark interest in this emerging research area and to motivate potential practitioners by illustrating early successes. We also aspire to encourage a creative reimagining of the next generation of materials science infrastructure. To this end, we frame future investments in materials science and technology, hardware and software infrastructure, artificial intelligence and autonomy methods, and critical workforce development for autonomous research.", "date": "2021-09-01", "date_type": "published", "publication": "Matter", "volume": "4", "number": "9", "publisher": "Cell Press", "pagerange": "2702-2726", "id_number": "CaltechAUTHORS:20210729-223028773", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210729-223028773", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Pennsylvania" }, { "agency": "Air Force Research Laboratory (AFRL)" }, { "agency": "American Chemical Society" }, { "agency": "NSF", "grant_number": "DMR-1720530" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "19RXCOR322" }, { "agency": "NSF", "grant_number": "CMMI-1661412" }, { "agency": "NSF", "grant_number": "DMR-1928882" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "HR001118C0036" }, { "agency": "Camille and Henry Dreyfus Foundation", "grant_number": "TH-14-010" }, { "agency": "NSF", "grant_number": "DMR-1922234" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0144" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2021.06.036", "pub_year": "2021", "author_list": "Stach, Eric; DeCost, Brian; et el." }, { "id": "https://authors.library.caltech.edu/records/ztj05-21j03", "eprint_id": 110397, "eprint_status": "archive", "datestamp": "2023-08-20 04:58:42", "lastmod": "2023-10-23 19:38:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." }, "orcid": "0000-0003-2538-0794" }, { "id": "Evans-Jake-M", "name": { "family": "Evans", "given": "Jake M." }, "orcid": "0000-0002-8721-5316" }, { "id": "Meier-Madeline-C", "name": { "family": "Meier", "given": "Madeline C." }, "orcid": "0000-0003-1608-0810" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Decoupled electrochemical water-splitting systems: a review and perspective", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 The Royal Society of Chemistry 2021. \n\nSubmitted 24 Apr 2021; Accepted 02 Jul 2021; First published 07 Jul 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. MCM acknowledges a Graduate Research Fellowship from the National Science Foundation. MCM also acknowledges the Resnick Sustainability Institute at Caltech for fellowship support. \n\nConflicts of interest: NSL may become a consultant and equity holder in a future potential corporation that is seeking funding to focus on commercial development of catalysts and systems for the production and use of hydrogen.", "abstract": "Electrochemical water splitting is a promising technology to renewably generate hydrogen fuel from water. One particular drawback of conventional water splitting is that the hydrogen-forming reduction reaction is tightly coupled, both spatially and temporally, to the oxygen-forming oxidation reaction. This coupling poses challenges in both conventional and direct-solar-powered electrolysis systems, including gas crossover and separator degradation, sometimes necessitating the use of precious metal catalysts. In decoupled water splitting, the conventional electrolysis reactions are separated spatially, temporally, or both, via coupling to an intermediate redox mediator. Decoupled water-splitting systems are flexible and modular by nature, with other proposed benefits including facile coupling to renewable power sources, utilization of earth-abundant catalysts, and intrinsically safe operation. Here we review recent advances in decoupled water splitting and related fields, mainly categorizing decoupled systems by mediator phase and standard potential. We offer insight to how decoupling may be advantageous, and which tradeoffs need to be considered for practical implementation. We conclude our review with discussion of known technological hurdles and note opportunities for future discovery.", "date": "2021-09-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "14", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "4740-4759", "id_number": "CaltechAUTHORS:20210823-225400426", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210823-225400426", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/d1ee01226f", "pub_year": "2021", "author_list": "Ifkovits, Zachary P.; Evans, Jake M.; et el." }, { "id": "https://authors.library.caltech.edu/records/98z81-3ev19", "eprint_id": 110927, "eprint_status": "archive", "datestamp": "2023-08-22 11:04:14", "lastmod": "2023-10-23 17:39:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Di", "name": { "family": "Chen", "given": "Di" } }, { "id": "Bai-Yiwei", "name": { "family": "Bai", "given": "Yiwei" } }, { "id": "Ament-Sebastian-E", "name": { "family": "Ament", "given": "Sebastian" } }, { "id": "Zhao-Wenting", "name": { "family": "Zhao", "given": "Wenting" } }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" } }, { "id": "Selman-Bart", "name": { "family": "Selman", "given": "Bart" } }, { "id": "van-Dover-R-Bruce", "name": { "family": "van Dover", "given": "R. Bruce" }, "orcid": "0000-0002-6166-5650" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" } ] }, "title": "Automating crystal-structure phase mapping by combining deep learning with constraint reasoning", "ispublished": "pub", "full_text_status": "public", "keywords": "Computer science; Materials science", "note": "\u00a9 2021 Nature Publishing Group. \n\nReceived 30 September 2020; Accepted 23 July 2021; Published 16 September 2021. \n\nThe development of DRNets was supported by the US National Science Foundation, under the Expeditions in Computing award CCF-1522054 (C.P.G., B.S., J.M.G., D.C., S.A., Y.B. and W.Z.) and award CNS-1059284 (C.P.G.). DRNets for phase mapping and corresponding experimental work were also supported by the US AFOSR Multidisciplinary University Research Initiative (MURI) under award FA9550-18-1-0136 (R.B.v.D., C.P.G., B.S., J.M.G., D.C., Y.B. and S.A.), a compute cluster under the Defense University Research Instrumentation Program (DURIP), award W911NF-17-1-0187 (C.P.G.) and an award from the Toyota Research Institute (J.M.G., C.P.G., D.C., Y.B. and S.A.). Solar fuels experiments were supported by the US Department of Energy (DOE) under award DESC0004993 (J.M.G., D.A. and L.Z.) and solar photochemistry analysis in the context of the DRNets solution was supported by the US DOE under award DE-SC0020383 (J.M.G. and D.A.). We also thank J. Bai for assistance with running the IAFD baseline, A. Shinde for photoelectrochemistry experiments and R. Berstein for assistance with figure generation. \n\nData availability: Data are available from 'UDiscoverIt: Materials' (https://www.cs.cornell.edu/gomes/udiscoverit/?tag=materials) and also from GitHub (https://github.com/gomes-lab/DRNets-Nature-Machine-Intelligence). Source data are provided with this paper. \n\nCode availability: Code is available from 'UDiscoverIt: Materials' (https://www.cs.cornell.edu/gomes/udiscoverit/?tag=materials) and also from GitHub (https://github.com/gomes-lab/DRNets-Nature-Machine-Intelligence). \n\nAuthor Contributions: C.P.G. conceived and managed the overall study. J.M.G. and C.P.G. conceived and managed the crystal-structure phase mapping project. D.C. and C.P.G. conceived the MNIST-Sudoku project. D.C. and C.P.G. conceptualized the DRNets. D.C. developed and implemented DRNets, in particular DRNets for MNIST-Sudoku and crystal-structure phase mapping. Y.B. performed the large-scale experiments, assisted on implementing DRNets for MNIST-Sudoku, and carried out baseline comparisons for MNIST-Sudoku. S.A. performed background subtraction for the Bi\u2013Cu\u2013V\u2013O system. W.Z. implemented baselines for crystal-structure phase mapping and assisted on generating MNIST-Sudoku data. L.Z. and D.G. generated phase mapping datasets and interpreted and validated solutions. C.P.G., D.C. and J.M.G. were the main authors of the manuscript, with contributions from B.S. and R.B.v.D. and comments from all authors. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Machine Intelligence thanks Artur Garcez, Olga Kononova and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nSubmitted - 2108.09523.pdf
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", "abstract": "Crystal-structure phase mapping is a core, long-standing challenge in materials science that requires identifying crystal phases, or mixtures thereof, in X-ray diffraction measurements of synthesized materials. Phase mapping algorithms have been developed that excel at solving systems with up to several unique phase mixtures, where each phase has a readily distinguishable diffraction pattern. However, phase mapping is often beyond materials scientists' capabilities and also poses challenges to state-of-the-art algorithms due to complexities such as the existence of dozens of phase mixtures, alloy-dependent variation in the diffraction patterns and multiple compositional degrees of freedom, creating a major bottleneck in high-throughput materials discovery. Here we show how to automate crystal-structure phase mapping. We formulate phase mapping as an unsupervised pattern demixing problem and describe how to solve it using deep reasoning networks (DRNets). DRNets combine deep learning with constraint reasoning for incorporating prior scientific knowledge and consequently require only a modest amount of (unlabelled) data. DRNets compensate for the limited data by exploiting and magnifying the rich prior knowledge about the thermodynamic rules governing the mixtures of crystals. DRNets are designed with an interpretable latent space for encoding prior-knowledge domain constraints and seamlessly integrate constraint reasoning into neural network optimization. DRNets surpass previous approaches on crystal-structure phase mapping, unravelling the Bi\u2013Cu\u2013V oxide phase diagram and aiding the discovery of solar fuels materials.", "date": "2021-09", "date_type": "published", "publication": "Nature Machine Intelligence", "volume": "3", "number": "9", "publisher": "Nature Publishing Group", "pagerange": "812-822", "id_number": "CaltechAUTHORS:20210917-144224516", "issn": "2522-5839", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210917-144224516", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1522054" }, { "agency": "NSF", "grant_number": "CNS-1059284" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0187" }, { "agency": "Toyota Research Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Liquid-Sunlight-Alliance" } ] }, "doi": "10.1038/s42256-021-00384-1", "primary_object": { "basename": "42256_2021_384_Fig10_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig10_ESM.webp" }, "related_objects": [ { "basename": "42256_2021_384_Fig7_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig7_ESM.webp" }, { "basename": "42256_2021_384_Fig8_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig8_ESM.webp" }, { "basename": "42256_2021_384_MOESM8_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM8_ESM.xlsx" }, { "basename": "2108.09523.pdf", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/2108.09523.pdf" }, { "basename": "42256_2021_384_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM1_ESM.pdf" }, { "basename": "42256_2021_384_MOESM4_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM4_ESM.xlsx" }, { "basename": "42256_2021_384_MOESM5_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM5_ESM.xlsx" }, { "basename": "42256_2021_384_MOESM6_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM6_ESM.xlsx" }, { "basename": "42256_2021_384_MOESM7_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM7_ESM.xlsx" }, { "basename": "42256_2021_384_Fig12_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig12_ESM.webp" }, { "basename": "42256_2021_384_Fig13_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig13_ESM.webp" }, { "basename": "42256_2021_384_Fig9_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig9_ESM.webp" }, { "basename": "42256_2021_384_MOESM3_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM3_ESM.xlsx" }, { "basename": "42256_2021_384_Fig11_ESM.webp", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_Fig11_ESM.webp" }, { "basename": "42256_2021_384_MOESM2_ESM.xlsx", "url": "https://authors.library.caltech.edu/records/98z81-3ev19/files/42256_2021_384_MOESM2_ESM.xlsx" } ], "pub_year": "2021", "author_list": "Chen, Di; Bai, Yiwei; et el." }, { "id": "https://authors.library.caltech.edu/records/ks44v-chc25", "eprint_id": 111078, "eprint_status": "archive", "datestamp": "2023-10-04 22:00:51", "lastmod": "2023-10-24 15:33:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guerrero-Vela-Pedro-Pablo", "name": { "family": "Guerrero Vela", "given": "Pedro Pablo" }, "orcid": "0000-0001-5766-2038" }, { "id": "Polk-James-E", "name": { "family": "Polk", "given": "James E." }, "orcid": "0000-0002-1225-4695" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Lopez-Ortega-Alejandro", "name": { "family": "Lopez Ortega", "given": "Alejandro" }, "orcid": "0000-0002-3781-2956" } ] }, "title": "Dynamic thermal behavior of polycrystalline LaB\u2086 hollow cathodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 Author(s). Published under an exclusive license by AIP Publishing. \n\nSubmitted: 31 May 2021 \u00b7 Accepted: 4 August 2021 \u00b7 Published Online: 25 August 2021. \n\nThis paper is part of the Special Topic on Physics of Electric Propulsion. \n\nThe support of the joint NASA GRC and JPL development of HERMeS by NASA's Space Technology Mission Directorate through the Solar Electric Propulsion Technology Demonstration Mission project is gratefully acknowledged. Portions of the research described in this paper were carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration. The research was, in part, carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. This work was supported through the Office of Science of the U.S. Department of Energy (DOE) under Award No. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. \n\nDATA AVAILABILITY. The data that support the findings of this study are available from the corresponding author upon reasonable request.\n\nPublished - 083303_1_online.pdf
", "abstract": "Lanthanum hexaboride (LaB\u2086) hollow cathodes have demonstrated a capability for long life operation, which is critical to many space exploration missions. Thermal characterization of LaB\u2086 hollow cathodes has revealed lower than expected electron emitter temperatures when the cathode reaches a steady state. This phenomenon is observed at discharge currents ranging from 5 to 35\u2009A and xenon mass flow rates of 5\u201325\u2009SCCM in cathodes with three different orifice diameters. Thus, the currently accepted value of the work function for polycrystalline LaB\u2086, 2.67\u2009eV, does not describe well the emission characteristics of LaB\u2086 hollow cathodes operating with internal gas discharges at a steady state. We use empirically measured temperatures combined with a model of the hollow cathode emitter and xenon discharge to estimate the value of the work function, yielding a value ranging from 2.1 to 2.44\u2009eV. This lower work function value implies that LaB\u2086 hollow cathodes are expected to have even longer lifetimes than previously anticipated, further establishing them as a more suited alternative to other conventional cathode technologies for the task of long duration travel. Direct measurements of the work function as a function of depth on a hollow cathode emitter using x-ray photoelectron spectroscopy and ion beam milling indicate that the work function decreases with depth. We postulate several mechanisms that could explain the observed work function enhancement. Altogether, our results have important implications to the design, study approach, and operation of LaB\u2086 cathodes and potentially other cathodes with hollow configuration. Finally, our work opens the question of why the work function is reduced upon interaction with Xe plasma.", "date": "2021-08-28", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "130", "number": "8", "publisher": "American Institute of Physics", "pagerange": "Art. No. 083303", "id_number": "CaltechAUTHORS:20210927-225706729", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210927-225706729", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NASA/JPL/Caltech" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/5.0058607", "primary_object": { "basename": "083303_1_online.pdf", "url": "https://authors.library.caltech.edu/records/ks44v-chc25/files/083303_1_online.pdf" }, "pub_year": "2021", "author_list": "Guerrero Vela, Pedro Pablo; Polk, James E.; et el." }, { "id": "https://authors.library.caltech.edu/records/kk91s-n4712", "eprint_id": 109418, "eprint_status": "archive", "datestamp": "2023-08-22 10:53:42", "lastmod": "2023-10-23 17:55:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Lei", "name": { "family": "Wang", "given": "Lei" }, "orcid": "0000-0002-1931-7767" }, { "id": "Peng-Hongjie", "name": { "family": "Peng", "given": "Hongjie" } }, { "id": "Lamaison-Sarah", "name": { "family": "Lamaison", "given": "Sarah" } }, { "id": "Qi-Zhifu", "name": { "family": "Qi", "given": "Zhifu" } }, { "id": "Koshy-David-M", "name": { "family": "Koshy", "given": "David M." } }, { "id": "Stevens-Michaela-B", "name": { "family": "Stevens", "given": "Michaela Burke" }, "orcid": "0000-0003-3584-0600" }, { "id": "Wakerley-David", "name": { "family": "Wakerley", "given": "David" } }, { "id": "Zamora-Zeled\u00f3n-Jos\u00e9-A", "name": { "family": "Zamora Zeled\u00f3n", "given": "Jos\u00e9 A." } }, { "id": "King-Laurie-A", "name": { "family": "King", "given": "Laurie A." } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Fontecave-Marc", "name": { "family": "Fontecave", "given": "Marc" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John" }, "orcid": "0000-0002-2863-5265" }, { "id": "Abild-Pedersen-Frank", "name": { "family": "Abild-Pedersen", "given": "Frank" } }, { "id": "Jaramillo-Thomas-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" }, { "id": "Hahn-Christopher", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" } ] }, "title": "Bimetallic effects on Zn-Cu electrocatalysts enhance activity and selectivity for the conversion of CO\u2082 to CO", "ispublished": "pub", "full_text_status": "public", "keywords": "CO2 reduction; CO formation; bimetallic effect; electrocatalysis", "note": "\u00a9 2021 Elsevier. \n\nReceived 26 January 2021, Revised 18 April 2021, Accepted 6 May 2021, Available online 7 June 2021. \n\nThe galvanic-exchange synthesis, physical and electrochemical characterization, and DFT calculations on Zn-Cu bimetallics are based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. Combinatorial high-throughput measurements of sputtered Cu-Zn catalysts are based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF), supported by the National Science Foundation under Award ECCS-1542152. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. Additional thanks go to the Stanford NMR Facility. L.W. thanks the Knut and Alice Wallenberg Foundation for financial support and the National University of Singapore and Ministry of Education \u2013 Singapore for its financial support through Tier-1 projects with grants R-279-000-622-133 and R-279-000-622-731. \n\nAuthor contributions. Conceptualization, L.W., T.F.J., and C.H.; methodology, L.W., H.P., S.L., Z.Q., D.K., M.B.S., J.A.Z.Z., D.W., L.K., L.Z., and Y.L.; investigation, L.W., H.P., S.L., Z.Q., D.K., M.B.S., J.A.Z.Z., D.W., L.K., L.Z., Y.L., and M.F.; writing \u2013 original draft, L.W., H.P., and S.L.; writing \u2013 review & editing, L.W., H.P., S.L., Z.Q., D.K., M.B.S., J.A.Z.Z., D.W., L.K., L.Z., Y.L., M.F., J.G., F.A.-P., T.F.J., and C.H.; funding acquisition, J.G., F.A.-P., T.F.J., and C.H.; supervision, J.G., F.A.-P., T.F.J., and C.H. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 1-s2.0-S2667109321000373-mmc1.pdf
", "abstract": "We report an active zinc-copper (Zn-Cu) bimetallic electrocatalyst for CO\u2082 reduction to CO, prepared by a facile galvanic procedure. Under moderate overpotentials, Zn-Cu catalysts that are Zn rich exhibit intrinsic activity for CO formation superior to that of pure Zn, Cu, and Ag, the last of which is the state-of-the-art catalyst in CO\u2082 electrolyzers. Combinatorial experiments involving catalysts prepared by physical vapor deposition reveal trends across the Zn-Cu system, corroborating the high CO selectivity unrivaled by other alloys and intermetallics. Physical and electrochemical characterization and first principles theory reveal that the origin of this synergy in intrinsic activity is an electronic effect from bimetallic Zn-Cu sites that stabilizes the carboxyl intermediate during CO\u2082 reduction to CO. Furthermore, by integrating Zn-Cu into gas-diffusion electrodes, we demonstrate that bimetallic effects lead to improved electrocatalytic performance at industrially relevant currents. These insights provide catalyst design principles that can guide future development of efficient and earth-abundant CO-producing electrocatalysts.", "date": "2021-08-19", "date_type": "published", "publication": "Chem Catalysis", "volume": "1", "number": "3", "publisher": "Cell Press", "pagerange": "663-680", "id_number": "CaltechAUTHORS:20210607-115054455", "issn": "2667-1093", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210607-115054455", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "NSF", "grant_number": "ECCS-1542152" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "Knut and Alice Wallenberg Foundation" }, { "agency": "National University of Singapore" }, { "agency": "Ministry of Education (Singapore)", "grant_number": "R-279-000-622-133" }, { "agency": "Ministry of Education (Singapore)", "grant_number": "R-279-000-622-731" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.checat.2021.05.006", "primary_object": { "basename": "1-s2.0-S2667109321000373-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/kk91s-n4712/files/1-s2.0-S2667109321000373-mmc1.pdf" }, "pub_year": "2021", "author_list": "Wang, Lei; Peng, Hongjie; et el." }, { "id": "https://authors.library.caltech.edu/records/xcj09-vkg35", "eprint_id": 110630, "eprint_status": "archive", "datestamp": "2023-08-20 04:44:40", "lastmod": "2023-10-23 19:46:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nunez-Paul-D", "name": { "family": "Nunez", "given": "Paul" }, "orcid": "0000-0001-7039-0516" }, { "id": "Cab\u00e1n-Acevedo-Miguel", "name": { "family": "Cab\u00e1n-Acevedo", "given": "Miguel" }, "orcid": "0000-0003-0054-8044" }, { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Kennedy-Kathleen-M", "name": { "family": "Kennedy", "given": "Kathleen" }, "orcid": "0000-0002-7125-4871" }, { "id": "Molina-Villarino-Andr\u00e9s", "name": { "family": "Molina Villarino", "given": "Andr\u00e9s" }, "orcid": "0000-0003-3272-5156" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Origin of the Electrical Barrier in Electrolessly Deposited Platinum Nanoparticles on p-Si Surfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Platinum, Layers, Electrodes, Deposition, X-ray photoelectron spectroscopy", "note": "\u00a9 2021 American Chemical Society. \n\nReceived 6 April 2021. Revised 10 June 2021. Published online 6 August 2021. Published in issue 19 August 2021. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under Award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. P.N. acknowledges support from the National Science Foundation for graduate research fellowships. Research was in part carried out at the Molecular Materials Resource Center of the Beckman Institute and at the Microanalysis Center of the California Institute of Technology. The authors thank Dr. K. Papadantonakis for assistance with editing this manuscript, and B.S.B. thanks Dr. S. Maldonado for helpful discussions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp1c03072_si_001.pdf
", "abstract": "Pt deposited by either sputtering or electron-beam (e-beam) evaporation on p-Si forms an ohmic contact, with zero photovoltage and very little photogenerated charge-carrier collection. However, electro- or electroless deposition of Pt onto p-Si produces a rectifying junction that generates a photovoltage of \u223c300 mV under simulated 1 sun illumination. To explain these differences, we have characterized junctions formed by electroless or e-beam deposition of Pt onto H-terminated or oxide-coated p-Si substrates using impedance spectroscopy, X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and electrochemical current density vs potential (J\u2013E) characteristics. When Pt was deposited electrolessly, XPS and TEM measurements revealed a thin interfacial SiO_x layer of 1\u20136 nm thickness under the Pt overlayer. Moreover, open-circuit potential measurements under illumination on electrolessly deposited Pt on a p-Si electrode showed that the junction was a function of the Nernstian potential of the contacting electrolyte solution. Creating an analogous junction by e-beam deposition of Pt required oxidation of the Si surface prior to Pt deposition, followed by etching in HF to remove oxide on the exposed Si surface. The resulting structure has both an interfacial SiO_x layer under the Pt and a H-terminated Si surface on the bare areas. Additionally, under a H\u2082 atmosphere, Pt can adsorb hydrogen that can diffuse to the SiO_x/Pt interface and produce a dipole layer. This information allowed formulation of a model for the charge transfer across p-Si/SiO_x/Pt interfaces. When in contact with a solution having a kinetically facile redox couple, the current is carried across the Si/electrolyte interface, and the electrode has the properties of a semiconductor/liquid junction. In contrast, when in contact with a solution with a large kinetic barrier to interfacial charge transfer, such as the hydrogen evolution reaction, the current instead passes predominantly through the SiO_x layer to the Pt and then reacts with protons in the solution. In this situation, the junction to the semiconductor is buried and occurs at the Si/SiO_x/Pt interface. The Si/SiO_x/Pt contact displays an increase in barrier height due to the hydrogen-induced dipoles. Consequently, the barrier height for an electrode made by electroless deposition of Pt onto Si is determined by the pathway that the electrons traverse to reach the solution.", "date": "2021-08-19", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "125", "number": "32", "publisher": "American Chemical Society", "pagerange": "17660-17670", "id_number": "CaltechAUTHORS:20210830-230029107", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210830-230029107", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.1c03072", "primary_object": { "basename": "jp1c03072_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xcj09-vkg35/files/jp1c03072_si_001.pdf" }, "pub_year": "2021", "author_list": "Nunez, Paul; Cab\u00e1n-Acevedo, Miguel; et el." }, { "id": "https://authors.library.caltech.edu/records/krd1g-zev04", "eprint_id": 109873, "eprint_status": "archive", "datestamp": "2023-08-22 10:48:20", "lastmod": "2023-10-23 18:12:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Buckley-Aya-K", "name": { "family": "Buckley", "given": "Aya K." } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Oh-Myoung-Hwan", "name": { "family": "Oh", "given": "Myoung Hwan" } }, { "id": "Su-Gregory-M", "name": { "family": "Su", "given": "Gregory M." } }, { "id": "Garrison-Jennifer", "name": { "family": "Garrison", "given": "Jennifer" } }, { "id": "Utan-Sean-W", "name": { "family": "Utan", "given": "Sean W." } }, { "id": "Zhu-Chenhui", "name": { "family": "Zhu", "given": "Chenhui" } }, { "id": "Toste-F-Dean", "name": { "family": "Toste", "given": "F. Dean" }, "orcid": "0000-0001-8018-2198" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" } ] }, "title": "Approaching 100% Selectivity at Low Potential on Ag for Electrochemical CO\u2082 Reduction to CO Using a Surface Additive", "ispublished": "pub", "full_text_status": "public", "keywords": "electrochemical CO\u2082 reduction; surface additives; interfaces; silver; molecular dynamics", "note": "\u00a9 2021 The Authors. Published by American Chemical Society. Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) \n\nReceived: February 23, 2021;\nRevised: June 15, 2021;\nPublished: July 8, 2021.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This research used beamline 7.3.3 of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. Dr. Michelle Lee is acknowledged for helpful discussions.\n\nAuthor Contributions:\nA.K.B. and T.C. contributed equally. A.K.B., F.D.T., and F.M.T. conceptualized the project. A.K.B., J.G., and S.W.U carried out the experiments, and T.C. carried out the theoretical calculations. M.H.O. helped with data interpretation. C.Z. collected scattering data. G.M.S. and C.Z. analyzed and interpreted scattering data. F.D.T. and F.M.T. supervised the experimental portion and W.A.G. the theoretical portion of the project. A.K.B., T.C., W.A.G., and F.M.T wrote the original manuscript. All authors proofread, commented on, and approved the final manuscript for submission.\n\nThe authors declare no competing financial interest.\n\nPublished - acscatal.1c00830.pdf
Supplemental Material - cs1c00830_si_001.pdf
", "abstract": "We report the discovery of a quaternary ammonium surface additive for CO\u2082 reduction on Ag surfaces that changes the Faradaic efficiency for CO from 25% on Ag foil to 97%, while increasing the current density for CO production by a factor of 9 from 0.14 to 1.21 mA/cm\u00b2 and reducing the current density for H\u2082 production by a factor of 440 from 0.44 to 0.001 mA/cm\u00b2. Using ReaxFF reactive molecular dynamics, we find that the surface additive with the highest selectivity, dihexadecyldimethylammonium bromide, promotes substantial population of CO\u2082 near the Ag surface along with sufficient H\u2082O to activate the CO\u2082. While a critical number of water molecules is required in the reduction of CO\u2082 to CO, the trend in selectivity strongly correlates with the availability of CO\u2082 molecules. We demonstrate that the ordering of the cationic modifiers plays a significant role around the active site, thus determining reaction selectivity. The dramatic improvement by addition of a simple surface additive suggests an additional strategy in electrocatalysis.", "date": "2021-08-06", "date_type": "published", "publication": "ACS Catalysis", "volume": "11", "number": "15", "publisher": "American Chemical Society", "pagerange": "9034-9042", "id_number": "CaltechAUTHORS:20210716-164306725", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210716-164306725", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1476", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.1c00830", "primary_object": { "basename": "acscatal.1c00830.pdf", "url": "https://authors.library.caltech.edu/records/krd1g-zev04/files/acscatal.1c00830.pdf" }, "related_objects": [ { "basename": "cs1c00830_si_001.pdf", "url": "https://authors.library.caltech.edu/records/krd1g-zev04/files/cs1c00830_si_001.pdf" } ], "pub_year": "2021", "author_list": "Buckley, Aya K.; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/w5ppg-n5n92", "eprint_id": 101280, "eprint_status": "archive", "datestamp": "2023-08-22 10:17:05", "lastmod": "2023-10-23 16:56:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" } }, { "id": "Lu-I-Te", "name": { "family": "Lu", "given": "I-Te" } }, { "id": "Maliyov-Ivan", "name": { "family": "Maliyov", "given": "Ivan" } }, { "id": "Tong-Xiao", "name": { "family": "Tong", "given": "Xiao" } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Perturbo: A software package for ab initio electron\u2013phonon interactions, charge transport and ultrafast dynamics", "ispublished": "pub", "full_text_status": "public", "keywords": "Charge transport; Ultrafast dynamics; Electron\u2013phonon interactions; Wannier functions", "note": "\u00a9 2021 Elsevier B.V. \n\nReceived 7 February 2020, Accepted 28 February 2021, Available online 22 March 2021. \n\nThe review of this paper was arranged by Prof. D.P. Landau. \n\nWe thank V.A. Jhalani and B.K. Chang for fruitful discussions. This work was supported by the National Science Foundation, United States under Grants No. ACI-1642443 for code development and DMR-1750613 for theory development. J.-J.Z. acknowledges support by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy, United States under Award No. DE-SC0004993. J.P. acknowledges support by the Korea Foundation for Advanced Studies, South Korea. I-T.L. was supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant FA9550-18-1-0280. X.T. was supported by the Resnick Institute at Caltech. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy, United States under Contract No. DE-AC02-05CH11231. \n\nThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\n\nSubmitted - 2002.02045.pdf
", "abstract": "Perturbo is a software package for first-principles calculations of charge transport and ultrafast carrier dynamics in materials. The current version focuses on electron\u2013phonon interactions and can compute phonon-limited transport properties such as the conductivity, carrier mobility and Seebeck coefficient. It can also simulate the ultrafast nonequilibrium electron dynamics in the presence of electron\u2013phonon scattering. Perturbo uses results from density functional theory and density functional perturbation theory calculations as input, and employs Wannier interpolation to reduce the computational cost. It supports norm-conserving and ultrasoft pseudopotentials, spin\u2013orbit coupling, and polar electron\u2013phonon interactions for bulk and 2D materials. Hybrid MPI plus OpenMP parallelization is implemented to enable efficient calculations on large systems (up to at least 50 atoms) using high-performance computing. Taken together, Perturbo provides efficient and broadly applicable ab initio tools to investigate electron\u2013phonon interactions and carrier dynamics quantitatively in metals, semiconductors, insulators, and 2D materials. \n\nProgram summary: \n\nProgram Title: Perturbo; \n\nCPC Library link to program files: https://doi.org/10.17632/34m2p6v79t.1; \n\nDeveloper's repository link: https://perturbo-code.github.io; \n\nLicensing provisions: GNU General Public Licence 3.0;\n\nProgramming language: Fortran, Python; \n\nExternal routines/libraries: LAPACK, HDF5, MPI, OpenMP, FFTW, Quantum-ESPRESSO, Wannier90; \n\nNature of problem: Computing transport properties from first-principles in materials, including the electrical conductivity, carrier mobility and Seebeck coefficient; Simulating ultrafast nonequilibrium electron dynamics, such as the relaxation of excited carriers via interactions with phonons. \n\nSolution method: We implement the first-principles Boltzmann transport equation, which employs materials properties such as the electronic structure, lattice dynamics, and electron\u2013phonon collision terms computed with density functional theory and density functional perturbation theory. The Boltzmann transport equation is solved numerically to compute charge transport and simulate ultrafast carrier dynamics. Wannier interpolation is employed to reduce the computational cost. \n\nAdditional comments: Hybrid MPI plus OpenMP parallelization is implemented to run large calculations and take advantage of high-performance computing. Most results are output to HDF5 file format, which is portable and convenient for post-processing using high-level languages such as Python and Julia.", "date": "2021-07", "date_type": "published", "publication": "Computer Physics Communications", "volume": "264", "publisher": "Elsevier", "pagerange": "Art. No. 107970", "id_number": "CaltechAUTHORS:20200213-150248226", "issn": "0010-4655", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200213-150248226", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1016/j.cpc.2021.107970", "primary_object": { "basename": "2002.02045.pdf", "url": "https://authors.library.caltech.edu/records/w5ppg-n5n92/files/2002.02045.pdf" }, "pub_year": "2021", "author_list": "Zhou, Jin-Jian; Park, Jinsoo; et el." }, { "id": "https://authors.library.caltech.edu/records/hj9xm-qgr72", "eprint_id": 109407, "eprint_status": "archive", "datestamp": "2023-08-20 03:38:32", "lastmod": "2023-10-23 17:55:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Guiji", "name": { "family": "Liu", "given": "Guiji" }, "orcid": "0000-0002-3943-4119" }, { "id": "Lee-Michelle", "name": { "family": "Lee", "given": "Michelle" } }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Zeng-Guosong", "name": { "family": "Zeng", "given": "Guosong" } }, { "id": "Eichhorn-Johanna", "name": { "family": "Eichhorn", "given": "Johanna" } }, { "id": "Buckley-Aya-K", "name": { "family": "Buckley", "given": "Aya K." } }, { "id": "Toste-F-Dean", "name": { "family": "Toste", "given": "F. Dean" }, "orcid": "0000-0001-8018-2198" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" } ] }, "title": "CO\u2082 reduction on pure Cu produces only H\u2082 after subsurface O is depleted: Theory and experiment", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 The Author(s). Published under the PNAS license. \n\nEdited by Michael L. Klein, Temple University, Philadelphia, PA, and approved April 13, 2021 (received for review June 18, 2020) \n\nThis study is based on work initiated with funding from the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993 and completed with funding from the Liquid Sunlight Alliance (LiSA), which is supported by the US DOE, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award DE-SC0021266. Raman spectroscopy and some of the theoretical calculations were specifically supported by LiSA. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the US DOE under Contract No. DE-AC02-05CH11231. These studies used the Extreme Science and Engineering Discovery Environment which is supported by National Science Foundation Grant ACI-1548562. \n\nG.L., M.L., and S.K. contributed equally to this work. \n\nAuthor contributions: G.L., M.L., S.K., F.D.T., W.A.G., and F.M.T. designed research; G.L., M.L., S.K., and G.Z. performed research; J.E. and A.K.B. performed preliminary measurements; G.L., M.L., S.K., W.A.G., and F.M.T. analyzed the data; and G.L., M.L., S.K., F.D.T., W.A.G., and F.M.T. wrote the paper. \n\nData Availability. All study data are included in the article and/or SI Appendix. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.2012649118/-/DCSupplemental.\n\nPublished - e2012649118.full.pdf
Supplemental Material - pnas.2012649118.sapp.pdf
", "abstract": "We elucidate the role of subsurface oxygen on the production of C\u2082 products from CO\u2082 reduction over Cu electrocatalysts using the newly developed grand canonical potential kinetics density functional theory method, which predicts that the rate of C\u2082 production on pure Cu with no O is \u223c500 times slower than H\u2082 evolution. In contrast, starting with Cu\u2082O, the rate of C\u2082 production is >5,000 times faster than pure Cu(111) and comparable to H\u2082 production. To validate these predictions experimentally, we combined time-dependent product detection with multiple characterization techniques to show that ethylene production decreases substantially with time and that a sufficiently prolonged reaction time (up to 20 h) leads only to H\u2082 evolution with ethylene production \u223c1,000 times slower, in agreement with theory. This result shows that maintaining substantial subsurface oxygen is essential for long-term C\u2082 production with Cu catalysts.", "date": "2021-06-08", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "118", "number": "23", "publisher": "National Academy of Sciences", "pagerange": "Art. No. e2012649118", "id_number": "CaltechAUTHORS:20210606-014012159", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210606-014012159", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1466", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.2012649118", "pmcid": "PMC8201769", "primary_object": { "basename": "e2012649118.full.pdf", "url": "https://authors.library.caltech.edu/records/hj9xm-qgr72/files/e2012649118.full.pdf" }, "related_objects": [ { "basename": "pnas.2012649118.sapp.pdf", "url": "https://authors.library.caltech.edu/records/hj9xm-qgr72/files/pnas.2012649118.sapp.pdf" } ], "pub_year": "2021", "author_list": "Liu, Guiji; Lee, Michelle; et el." }, { "id": "https://authors.library.caltech.edu/records/mzs0c-9a531", "eprint_id": 109615, "eprint_status": "archive", "datestamp": "2023-08-20 03:30:32", "lastmod": "2023-10-20 23:16:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kong-Shufeng", "name": { "family": "Kong", "given": "Shufeng" } }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Materials representation and transfer learning for multi-property prediction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nSubmitted: 9 February 2021. Accepted: 28 May 2021. Published Online: 23 June 2021. \n\nThis paper is part of the special collection on Autonomous (AI-driven) Materials ScienceThis paper is part of the special collection on Autonomous (AI-driven) Materials Science. \n\nThis work was funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0020383 (data curation, design of multi-property prediction setting and transfer setting, model evaluation) and by the Toyota Research Institute through the Accelerated Materials Design and Discovery program (development of machine learning models). The authors thank Santosh K. Suram for assistance with curation of the dataset. \n\nDATA AVAILABILITY. The data that support the findings of this study are available at https://data.caltech.edu/records/1878. The source code and additional data for H-CLMP are available at https://www.cs.cornell.edu/gomes/udiscoverit/?tag=materials. The source code for H-CLMP and the cWGAN for transfer learning are also available at https://github.com/gomes-lab/H-CLMP.\n\nPublished - 5.0047066.pdf
Accepted Version - 2106.02225.pdf
Submitted - materials-representation-and-transfer-learning-for-multi-property-prediction.pdf
", "abstract": "The adoption of machine learning in materials science has rapidly transformed materials property prediction. Hurdles limiting full capitalization of recent advancements in machine learning include the limited development of methods to learn the underlying interactions of multiple elements as well as the relationships among multiple properties to facilitate property prediction in new composition spaces. To address these issues, we introduce the Hierarchical Correlation Learning for Multi-property Prediction (H-CLMP) framework that seamlessly integrates: (i) prediction using only a material's composition, (ii) learning and exploitation of correlations among target properties in multi-target regression, and (iii) leveraging training data from tangential domains via generative transfer learning. The model is demonstrated for prediction of spectral optical absorption of complex metal oxides spanning 69 three-cation metal oxide composition spaces. H-CLMP accurately predicts non-linear composition-property relationships in composition spaces for which no training data are available, which broadens the purview of machine learning to the discovery of materials with exceptional properties. This achievement results from the principled integration of latent embedding learning, property correlation learning, generative transfer learning, and attention models. The best performance is obtained using H-CLMP with transfer learning [H-CLMP(T)] wherein a generative adversarial network is trained on computational density of states data and deployed in the target domain to augment prediction of optical absorption from composition. H-CLMP(T) aggregates multiple knowledge sources with a framework that is well suited for multi-target regression across the physical sciences.", "date": "2021-06", "date_type": "published", "publication": "Applied Physics Reviews", "volume": "8", "number": "2", "publisher": "American Institute of Physics", "pagerange": "Art. No. 021409", "id_number": "CaltechAUTHORS:20210626-225301174", "issn": "1931-9401", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210626-225301174", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" }, { "agency": "Toyota Research Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/5.0047066", "primary_object": { "basename": "2106.02225.pdf", "url": "https://authors.library.caltech.edu/records/mzs0c-9a531/files/2106.02225.pdf" }, "related_objects": [ { "basename": "5.0047066.pdf", "url": "https://authors.library.caltech.edu/records/mzs0c-9a531/files/5.0047066.pdf" }, { "basename": "materials-representation-and-transfer-learning-for-multi-property-prediction.pdf", "url": "https://authors.library.caltech.edu/records/mzs0c-9a531/files/materials-representation-and-transfer-learning-for-multi-property-prediction.pdf" } ], "pub_year": "2021", "author_list": "Kong, Shufeng; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/xp74a-j6454", "eprint_id": 106897, "eprint_status": "archive", "datestamp": "2023-08-20 03:24:02", "lastmod": "2023-10-23 15:09:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Nien-En", "name": { "family": "Lee", "given": "Nien-En" }, "orcid": "0000-0002-3172-7750" }, { "id": "Chen-Hsiao-Yi", "name": { "family": "Chen", "given": "Hsiao-Yi" }, "orcid": "0000-0003-1962-5767" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Facile ab initio approach for self-localized polarons from canonical transformations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Physical Society. \n\nReceived 9 November 2020; revised 24 April 2021; accepted 8 June 2021; published 24 June 2021. \n\nThis work was supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant No. FA9550-18-1-0280. J.-J.Z. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. H.-Y.C. acknowledges support by the J. Yang Fellowship. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevMaterials.5.063805.pdf
Submitted - 2011.03620.pdf
", "abstract": "Electronic states in a crystal can localize due to strong electron-phonon (e-ph) interactions, forming so-called small polarons. Methods to predict the formation and energetics of small polarons are either computationally costly or not geared toward quantitative predictions. Here we show a formalism based on canonical transformations to compute the polaron formation energy and wave function using ab initio e-ph interactions. Comparison of the calculated polaron and band-edge energies allows us to determine whether charge carriers in a material favor a localized small polaron over a delocalized Bloch state. Due to its low computational cost, our approach enables efficient studies of the formation and energetics of small polarons, as we demonstrate by investigating electron and hole polaron formation in alkali halides and metal oxides and peroxides. We outline refinements of our scheme and extensions to compute transport in the polaron hopping regime.", "date": "2021-06", "date_type": "published", "publication": "Physical Review Materials", "volume": "5", "number": "6", "publisher": "American Physical Society", "pagerange": "Art. No. 063805", "id_number": "CaltechAUTHORS:20201203-151018693", "issn": "2475-9953", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201203-151018693", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "J. Yang Family and Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevMaterials.5.063805", "primary_object": { "basename": "2011.03620.pdf", "url": "https://authors.library.caltech.edu/records/xp74a-j6454/files/2011.03620.pdf" }, "related_objects": [ { "basename": "PhysRevMaterials.5.063805.pdf", "url": "https://authors.library.caltech.edu/records/xp74a-j6454/files/PhysRevMaterials.5.063805.pdf" } ], "pub_year": "2021", "author_list": "Lee, Nien-En; Chen, Hsiao-Yi; et el." }, { "id": "https://authors.library.caltech.edu/records/ywtpy-nka66", "eprint_id": 108544, "eprint_status": "archive", "datestamp": "2023-08-22 10:01:03", "lastmod": "2023-10-23 16:58:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Hao", "name": { "family": "Li", "given": "Hao" } }, { "id": "Kelly-Sara", "name": { "family": "Kelly", "given": "Sara" }, "orcid": "0000-0001-9424-2489" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Wang-Zhenbin", "name": { "family": "Wang", "given": "Zhenbin" }, "orcid": "0000-0002-7016-9245" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Anand-Megha", "name": { "family": "Anand", "given": "Megha" }, "orcid": "0000-0003-2707-3587" }, { "id": "Gunasooriya-G-T-Kasun-Kalhara", "name": { "family": "Gunasooriya", "given": "G. T. Kasun Kalhara" }, "orcid": "0000-0003-1258-7841" }, { "id": "Abraham-Christina-Susan", "name": { "family": "Abraham", "given": "Christina Susan" }, "orcid": "0000-0001-9991-0976" }, { "id": "Vijay-Sudarshan", "name": { "family": "Vijay", "given": "Sudarshan" }, "orcid": "0000-0001-8242-0161" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "N\u00f8rskov-Jens-K", "name": { "family": "N\u00f8rskov", "given": "Jens K." }, "orcid": "0000-0002-4427-7728" } ] }, "title": "Analysis of the limitations in the oxygen reduction activity of transition metal oxide surfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Density functional theory; Electrocatalysis; Energy; Fuel cells; Reaction kinetics and dynamics", "note": "\u00a9 The Author(s), under exclusive licence to Springer Nature Limited 2021. \n\nReceived 07 October 2020; Accepted 19 April 2021; Published 24 May 2021. \n\nWe thank I. Chorkendorff, Y. Zheng (Technical University of Denmark), T. F. Jaramillo (Stanford University) and J. H. Montoya (Toyota Research Institute) for all the helpful discussions. This work was supported by the Toyota Research Institute through the Accelerated Materials Design and Discovery program. \n\nData availability: The experimental data are available at https://data.caltech.edu/records/1632 (https://doi.org/10.22002/D1.1632). The computational data, which include the O, HO and HOO binding energies, the free energies of 4e\u2013 ORR, the optimized atomic coordinates and the scripts for structure modelling, are available at https://github.com/cattheory-oxides/data. All the data are available from the authors upon reasonable request. \n\nThese authors contributed equally: Hao Li, Sara Kelly. \n\nAuthor Contributions: H.L., S.K., J.M.G. and J.K.N. designed the study and wrote the paper. H.L., S.K., Z.W., M.A., G.T.K.K.G., C.S.A. and S.V. conducted the DFT calculations, data analysis, and microkinetic modelling. D.G., Y.W., J.A.H. and J.M.G. performed the high-throughput experiments. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Catalysis thanks Guofeng Wang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.\n\nSupplemental Material - 41929_2021_618_MOESM1_ESM.pdf
", "abstract": "The oxygen reduction reaction (ORR) is the key bottleneck in the performance of fuel cells. So far, the most active and stable electrocatalysts for the reaction are based on Pt group metals. Transition metal oxides (TMOs) constitute an alternative class of materials for achieving operational stability under oxidizing conditions. Unfortunately, TMOs are generally found to be less active than Pt. Here, we identify two reasons why it is difficult to find TMOs with a high ORR activity. The first is that TMO surfaces consistently bind oxygen atoms more weakly than transition metals do. This makes the breaking of the O\u2013O bond rate-determining for the broad range of TMO surfaces investigated here. The second is that electric field effects are stronger at TMO surfaces, which further makes O\u2013O bond breaking difficult. To validate the predictions and ascertain their generalizability for TMOs, we report experimental ORR catalyst screening for 7,798 unique TMO compositions that generally exhibit activity well below that of Pt.", "date": "2021-06", "date_type": "published", "publication": "Nature Catalysis", "volume": "4", "number": "6", "publisher": "Springer Nature", "pagerange": "463-468", "id_number": "CaltechAUTHORS:20210324-112501603", "issn": "2520-1158", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210324-112501603", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Toyota Research Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41929-021-00618-w", "primary_object": { "basename": "41929_2021_618_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/ywtpy-nka66/files/41929_2021_618_MOESM1_ESM.pdf" }, "pub_year": "2021", "author_list": "Li, Hao; Kelly, Sara; et el." }, { "id": "https://authors.library.caltech.edu/records/cfvz2-bqj12", "eprint_id": 109133, "eprint_status": "archive", "datestamp": "2023-08-22 09:52:13", "lastmod": "2023-10-23 17:40:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shi-Ye", "name": { "family": "Shi", "given": "Ye" }, "orcid": "0000-0002-5228-1604" }, { "id": "Ilic-Ognjen", "name": { "family": "Ilic", "given": "Ognjen" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Greer-J-R", "name": { "family": "Greer", "given": "Julia R." }, "orcid": "0000-0002-9675-1508" } ] }, "title": "All-day fresh water harvesting by microstructured hydrogel membranes", "ispublished": "pub", "full_text_status": "public", "keywords": "Devices for energy harvesting; Gels and hydrogels; Polymers", "note": "\u00a9 The Author(s) 2021. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 04 February 2021; Accepted 15 April 2021; Published 14 May 2021. \n\nWe thank Dr. Bruce S. Brunschwig for help with the solar simulator and Daryl Yee for help with 3D printing. We thank Shu Yan for help with drawing schemes. J.R.G. acknowledges the financial support of the Resnick Sustainability Institute and of the Caltech Space Solar Power Project. H.A.A. acknowledges financial support from the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. O. I. acknowledges support from the Caltech Space Solar Power Project and the 3M foundation. \n\nData availability: The data that support the findings of this study are available from the corresponding authors upon request. \n\nAuthor Contributions: Y.S. and J.R.G. conceived the idea. Y.S. performed materials fabrication and characterization. O.I. performed the numerical simulations. Y.S., O.I., H.A.A., and J.R.G. analyzed the data, discussed the results, and wrote the manuscript. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Guihua Yu and Jia Zhu for their contribution to the peer review of this work. Peer reviewer reports are available.\n\nPublished - s41467-021-23174-0.pdf
Supplemental Material - 41467_2021_23174_MOESM1_ESM.pdf
Supplemental Material - 41467_2021_23174_MOESM2_ESM.pdf
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Supplemental Material - 41467_2021_23174_MOESM4_ESM.mp4
", "abstract": "Solar steam water purification and fog collection are two independent processes that could enable abundant fresh water generation. We developed a hydrogel membrane that contains hierarchical three-dimensional microstructures with high surface area that combines both functions and serves as an all-day fresh water harvester. At night, the hydrogel membrane efficiently captures fog droplets and directionally transports them to a storage vessel. During the daytime, it acts as an interfacial solar steam generator and achieves a high evaporation rate of 3.64\u2009kg\u2009m\u207b\u00b2 h\u207b\u00b9 under 1 sun enabled by improved thermal/vapor flow management. With a homemade rooftop water harvesting system, this hydrogel membrane can produce fresh water with a daily yield of ~34\u2009L\u2009m\u207b\u00b2 in an outdoor test, which demonstrates its potential for global water scarcity relief.", "date": "2021-05-14", "date_type": "published", "publication": "Nature Communications", "volume": "12", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2797", "id_number": "CaltechAUTHORS:20210514-114309275", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210514-114309275", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Space Solar Power Project" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "3M Foundation" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" }, { "id": "Space-Solar-Power-Project" } ] }, "doi": "10.1038/s41467-021-23174-0", "pmcid": "PMC8121874", "primary_object": { "basename": "41467_2021_23174_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2021_23174_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM2_ESM.pdf" }, { "basename": "41467_2021_23174_MOESM3_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM3_ESM.pdf" }, { "basename": "41467_2021_23174_MOESM4_ESM.mp4", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/41467_2021_23174_MOESM4_ESM.mp4" }, { "basename": "s41467-021-23174-0.pdf", "url": "https://authors.library.caltech.edu/records/cfvz2-bqj12/files/s41467-021-23174-0.pdf" } ], "pub_year": "2021", "author_list": "Shi, Ye; Ilic, Ognjen; et el." }, { "id": "https://authors.library.caltech.edu/records/e6xcs-p1039", "eprint_id": 108829, "eprint_status": "archive", "datestamp": "2023-08-20 03:14:49", "lastmod": "2023-10-23 17:21:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Rengui", "name": { "family": "Li", "given": "Rengui" }, "orcid": "0000-0002-8099-0934" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Tian-Wenming", "name": { "family": "Tian", "given": "Wenming" } }, { "id": "Li-Can", "name": { "family": "Li", "given": "Can" }, "orcid": "0000-0002-9301-7850" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Unassisted Highly Selective Gas-Phase CO\u2082 Reduction with a Plasmonic Au/p-GaN Photocatalyst Using H\u2082O as an Electron Donor", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: February 21, 2021; Accepted: April 15, 2021; Published: April 20, 2021. \n\nThis work was performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and was primarily supported through the Office of Science of the U.S. Department of Energy (DOE) under Award No. DE SC0004993 (sample synthesis, gas-phase photocatalytic measurements, and photoelectrochemical measurements), and by the Liquid Sunlight Alliance under Award No. DESC0021266 (sample structural and morphological characterization and data analysis). Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. \n\nAuthor Contributions. R.L. and W.-H.C. contributed equally to this work. R.L., W.-H.C., and H.A.A. developed the ideas. R.L. and W.-H.C. fabricated the samples and performed the measurements, with assistance from M.H.R., J.S.D., and W.T. The manuscript was written by R.L., W.-H.C., J.S.D., and H.A.A., with input from all authors. All authors contributed to the discussion and interpretation of results as well as the presentation and preparation of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz1c00392_si_001.pdf
", "abstract": "Surface plasmon resonances in metal nanostructures enable the generation of nonequilibrium hot electron\u2013hole pairs, which has received wide interest as a means to drive chemical reactions at the nanoscale. However, harvesting hot holes in plasmonic heterostructures to drive oxidation reactions to balance the photocatalytic CO\u2082 reduction reaction has been challenging. Further, details of the balanced redox reaction pathways for gas-phase photocatalysis have been difficult to identify. Here, we report an Au/p-GaN plasmonic heterostructure photocatalyst in which unassisted, self-sustaining, highly selective photocatalytic CO\u2082 reduction to CO is directly balanced by water oxidation, operating under solar illumination. We find remarkable enhancements in CO yield for heterostructures that employ a metal/insulator/semiconductor configuration with an ultrathin aluminum oxide layer between composite Au/Cu nanoparticles and p-GaN. Our work underscores the potential for plasmonic heterostructure photocatalysts to perform selective and unassisted gas-phase photocatalytic CO\u2082 reduction to convert solar energy into chemical fuels.", "date": "2021-05-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "6", "number": "5", "publisher": "American Chemical Society", "pagerange": "1849-1856", "id_number": "CaltechAUTHORS:20210423-164855164", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210423-164855164", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.1c00392", "primary_object": { "basename": "nz1c00392_si_001.pdf", "url": "https://authors.library.caltech.edu/records/e6xcs-p1039/files/nz1c00392_si_001.pdf" }, "pub_year": "2021", "author_list": "Li, Rengui; Cheng, Wen-Hui; et el." }, { "id": "https://authors.library.caltech.edu/records/yvydk-hgf96", "eprint_id": 108933, "eprint_status": "archive", "datestamp": "2023-08-20 03:10:39", "lastmod": "2023-10-23 17:26:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wen-Yunzhou", "name": { "family": "Wen", "given": "Yunzhou" } }, { "id": "Chen-Peining", "name": { "family": "Chen", "given": "Peining" } }, { "id": "Wang-Lu", "name": { "family": "Wang", "given": "Lu" }, "orcid": "0000-0003-0552-1385" }, { "id": "Li-Shangyu", "name": { "family": "Li", "given": "Shangyu" } }, { "id": "Wang-Ziyun", "name": { "family": "Wang", "given": "Ziyun" }, "orcid": "0000-0002-2817-8367" }, { "id": "Abed-Jehad", "name": { "family": "Abed", "given": "Jehad" } }, { "id": "Mao-Xinnan", "name": { "family": "Mao", "given": "Xinnan" } }, { "id": "Min-Yimeng", "name": { "family": "Min", "given": "Yimeng" } }, { "id": "Dinh-Cao-Thang", "name": { "family": "Dinh", "given": "Cao Thang" }, "orcid": "0000-0001-9641-9815" }, { "id": "De-Luna-Phil", "name": { "family": "De Luna", "given": "Phil" }, "orcid": "0000-0002-7729-8816" }, { "id": "Huang-Rui", "name": { "family": "Huang", "given": "Rui" } }, { "id": "Zhang-Longsheng", "name": { "family": "Zhang", "given": "Longsheng" } }, { "id": "Wang-Lie", "name": { "family": "Wang", "given": "Lie" } }, { "id": "Wang-Liping", "name": { "family": "Wang", "given": "Liping" } }, { "id": "Nielsen-Robert-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Li-Huihui", "name": { "family": "Li", "given": "Huihui" }, "orcid": "0000-0002-3823-1010" }, { "id": "Zhuang-Taotao", "name": { "family": "Zhuang", "given": "Taotao" } }, { "id": "Ke-Changchun", "name": { "family": "Ke", "given": "Changchun" } }, { "id": "Voznyy-Oleksandr", "name": { "family": "Voznyy", "given": "Oleksandr" }, "orcid": "0000-0002-8656-5074" }, { "id": "Hu-Yongfeng", "name": { "family": "Hu", "given": "Yongfeng" } }, { "id": "Li-Youyong", "name": { "family": "Li", "given": "Youyong" }, "orcid": "0000-0002-5248-2756" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Zhang-Bo", "name": { "family": "Zhang", "given": "Bo" }, "orcid": "0000-0002-7853-979X" }, { "id": "Peng-Huisheng", "name": { "family": "Peng", "given": "Huisheng" }, "orcid": "0000-0003-3746-8494" }, { "id": "Sargent-Edward-H", "name": { "family": "Sargent", "given": "Edward H." }, "orcid": "0000-0003-0396-6495" } ] }, "title": "Stabilizing Highly Active Ru Sites by Suppressing Lattice Oxygen Participation in Acidic Water Oxidation", "ispublished": "pub", "full_text_status": "public", "keywords": "Oxides, Radiology, Electrocatalysts, Catalysts, Transition metals", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: January 12, 2021. \n\nThis work was supported by MOST (2016YFA0203302), NSFC (21634003, 51573027, 21875042, 21805044, and 21771170), STCSM (16JC1400702, 18QA140080, and 19QA140080), SHMEC (2017-01-07-00-07-E00062), and Yanchang Petroleum Group. This work was also supported by the Program for Eastern Scholars at Shanghai Institutions. This work was supported by the Ontario Research Fund - Research Excellence Program, NSERC, and the CIFAR Bio-Inspired Solar Energy program. The ex situ XAFS was carried out at the BL14W1 beamline, Shanghai Synchrotron Radiation Facility (SSRF). The in situ Ru K-edge and Ir L\u2083-edge XAFS was measured at the 1W1B beamline, Beijing Synchrotron Radiation Facility (BSRF). The in situ Ru L\u2083-edge measurements were carried out at the soft X-ray microcharacterization beamline (SXRMB) in Canadian Light Source (CLS). The STEM imaging part of this research was completed at the Analytical and Testing Center, Northwestern Polytechnical University. The Caltech studies were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993, by NSF (CBET-1805022), and by DOE AMO. \n\nAuthor Contributions: Y.W., P.C., L.W., and S.L. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja1c00384_si_001.pdf
", "abstract": "In hydrogen production, the anodic oxygen evolution reaction (OER) limits the energy conversion efficiency and also impacts stability in proton-exchange membrane water electrolyzers. Widely used Ir-based catalysts suffer from insufficient activity, while more active Ru-based catalysts tend to dissolve under OER conditions. This has been associated with the participation of lattice oxygen (lattice oxygen oxidation mechanism (LOM)), which may lead to the collapse of the crystal structure and accelerate the leaching of active Ru species, leading to low operating stability. Here we develop Sr\u2013Ru\u2013Ir ternary oxide electrocatalysts that achieve high OER activity and stability in acidic electrolyte. The catalysts achieve an overpotential of 190 mV at 10 mA cm\u207b\u00b2 and the overpotential remains below 225 mV following 1,500 h of operation. X-ray absorption spectroscopy and \u00b9\u2078O isotope-labeled online mass spectroscopy studies reveal that the participation of lattice oxygen during OER was suppressed by interactions in the Ru\u2013O\u2013Ir local structure, offering a picture of how stability was improved. The electronic structure of active Ru sites was modulated by Sr and Ir, optimizing the binding energetics of OER oxo-intermediates.", "date": "2021-05-05", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "17", "publisher": "American Chemical Society", "pagerange": "6482-6490", "id_number": "CaltechAUTHORS:20210503-115704310", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210503-115704310", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "2016YFA0203302" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21634003" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51573027" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21875042" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21805044" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21771170" }, { "agency": "Shanghai Science and Technology Committee (STCSM)", "grant_number": "16JC1400702" }, { "agency": "Shanghai Science and Technology Committee (STCSM)", "grant_number": "18QA140080" }, { "agency": "Shanghai Science and Technology Committee (STCSM)", "grant_number": "19QA140080" }, { "agency": "Shanghai Municipal Education", "grant_number": "2017-01-07-00-07-E00062" }, { "agency": "Yanchang Petroleum Group" }, { "agency": "Shanghai Institutions" }, { "agency": "Ontario Research Fund-Research Excellence" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-1805022" } ] }, "other_numbering_system": { "items": [ { "id": "1422", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.1c00384", "primary_object": { "basename": "ja1c00384_si_001.pdf", "url": "https://authors.library.caltech.edu/records/yvydk-hgf96/files/ja1c00384_si_001.pdf" }, "pub_year": "2021", "author_list": "Wen, Yunzhou; Chen, Peining; et el." }, { "id": "https://authors.library.caltech.edu/records/bdqxq-3wm96", "eprint_id": 108173, "eprint_status": "archive", "datestamp": "2023-08-20 02:48:29", "lastmod": "2023-10-23 16:30:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lindley-Sarah-A", "name": { "family": "Lindley", "given": "Sarah A." } }, { "id": "An-Qi", "name": { "family": "An", "given": "Qi" }, "orcid": "0000-0003-4838-6232" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Cooper-Jason-K", "name": { "family": "Cooper", "given": "Jason K." }, "orcid": "0000-0002-7953-4229" } ] }, "title": "Spatiotemporal Temperature and Pressure in Thermoplasmonic Gold Nanosphere-Water Systems", "ispublished": "pub", "full_text_status": "public", "keywords": "thermoplasmonics, transient absorption spectroscopy, molecular dynamics, hollow gold nanospheres,\nsurface plasmon resonance, heat transfer", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: November 23, 2020; Accepted: February 17, 2021; Published: February 23, 2021. \n\nWe acknowledge T. Yuzvinsky and the W.M. Keck Center for Nanoscale Optofluidics at University of California Santa Cruz for use of the FEI Quanta 3D dual beam microscope for SEM particle screening. We also acknowledge T. Yuzvinsky for fruitful discussion. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under contract no. DE-AC02-05CH11231. We acknowledge support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. Calculations were performed using the Cori cluster at the National Energy Research Scientific Computing Center (NERSC) at the LBNL supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Q.A. received support from American Chemical Society Petroleum Research Fund (PRF# 58754-DNI6). \n\nAuthor Contributions: S.A.L. and Q.A. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nn0c09804_si_001.pdf
", "abstract": "We offer a detailed investigation of the photophysical properties of plasmonic solid and hollow gold nanospheres suspended in water by combining ultrafast transient absorption (TA) spectroscopy with molecular dynamics (MD) simulations. TA reveals that hollow gold nanospheres (HGNs) exhibit faster excited state relaxation and larger amplitude acoustic phonon modes than solid gold nanoparticles of the same outer diameter. MD simulation carried out on full scale nanoparticle\u2013water models (over 10 million atoms) to simulate the temporal evolution (0\u2013100 ps) of the thermally excited particles (1000 or 1250 K) provides atomic-scale resolution of the spatiotemporal temperature and pressure maps, as well as visualization of the lattice vibrational modes. For the 1000 K HGN, temperatures upward of 500 K in the vicinity of the shell surface were observed, along with pressures up to several hundred MPa in the inner cavity, revealing potential use as a photoinduced nanoreactor. Our approach of combining TA and MD provides a path to better understanding how thermal\u2013structural properties (such as expansion and contraction) and thermal\u2013optical properties (such as modulated dielectrics) manifest themselves as TA signatures. The detailed picture of heat transfer at interfaces should help guide nanoparticle design for a wide range of applications that rely on photothermal conversion, including photothermal coupling agents for nanoparticle-mediated photothermal therapy and photocatalysts for light-driven chemical reactions.", "date": "2021-04-27", "date_type": "published", "publication": "ACS Nano", "volume": "15", "number": "4", "publisher": "American Chemical Society", "pagerange": "6276-6288", "id_number": "CaltechAUTHORS:20210224-122527044", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210224-122527044", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "American Chemical Society Petroleum Research Fund", "grant_number": "58754-DNI6" } ] }, "other_numbering_system": { "items": [ { "id": "1412", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsnano.0c09804", "primary_object": { "basename": "nn0c09804_si_001.pdf", "url": "https://authors.library.caltech.edu/records/bdqxq-3wm96/files/nn0c09804_si_001.pdf" }, "pub_year": "2021", "author_list": "Lindley, Sarah A.; An, Qi; et el." }, { "id": "https://authors.library.caltech.edu/records/0p5xg-31620", "eprint_id": 108586, "eprint_status": "archive", "datestamp": "2023-10-03 22:41:14", "lastmod": "2023-10-24 15:32:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Fontani-Herreros-Alex-M", "name": { "family": "Fontani-Herreros", "given": "Alex M." } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Dramatic HER Suppression on Ag Electrodes via Molecular Films for Highly Selective CO\u2082 to CO Reduction", "ispublished": "pub", "full_text_status": "public", "keywords": "electrocatalysis, CO\u2082RR, HER, solar fuels, modified electrodes, silver electrodes", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: January 24, 2021; Revised: March 13, 2021; Published: March 29, 2021. \n\nNMR, AFM, and XPS, SEM, and EDX measurements were collected at the NMR Facility (Division of Chemistry and Chemical Engineering), the Molecular Materials Research Center (Beckman Institute), and the Analytic Facilities (Division of Geological and Planetary Sciences) of the California Institute of Technology, respectively. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). J.C.P also acknowledges additional support from the Resnick Sustainability Institute at Caltech.\n\nThe authors declare no competing financial interest.\n\nAccepted Version - ACS_Catalysis_Ag_additives.pdf
Supplemental Material - cs1c00338_si_001.pdf
", "abstract": "The carbon dioxide reduction reaction (CO\u2082RR) in aqueous electrolytes suffers from efficiency loss due to the competitive hydrogen evolution reaction (HER). Developing efficient methods to suppress HER is a crucial step toward CO\u2082 utilization. Herein we report the selective conversion of CO\u2082 to CO on planar silver electrodes with Faradaic efficiencies >99% using simple pyridinium-based additives. Similar to our previous studies on copper electrodes, the additives form an organic film which alters CO\u2082RR selectivity. We report electrochemical kinetic and other mechanistic data to shed light on the role of these organic layers in suppressing HER. These data suggest that hydrogen production is selectively inhibited by the growth of a hydrophobic organic layer on the silver surface that limits proton but not CO\u2082 mass transport at certain applied potentials. The data also point to the involvement of a proton-transfer within the rate-determining step of the catalysis, instead of the commonly observed electron-transfer step for the case of planar Ag electrodes.", "date": "2021-04-16", "date_type": "published", "publication": "ACS Catalysis", "volume": "11", "number": "8", "publisher": "American Chemical Society", "pagerange": "4530-4537", "id_number": "CaltechAUTHORS:20210330-144253307", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210330-144253307", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acscatal.1c00338", "primary_object": { "basename": "ACS_Catalysis_Ag_additives.pdf", "url": "https://authors.library.caltech.edu/records/0p5xg-31620/files/ACS_Catalysis_Ag_additives.pdf" }, "related_objects": [ { "basename": "cs1c00338_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0p5xg-31620/files/cs1c00338_si_001.pdf" } ], "pub_year": "2021", "author_list": "Thevenon, Arnaud; Rosas-Hern\u00e1ndez, Alonso; et el." }, { "id": "https://authors.library.caltech.edu/records/p9s5b-en862", "eprint_id": 107980, "eprint_status": "archive", "datestamp": "2023-08-20 02:45:18", "lastmod": "2023-10-23 16:22:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Desai-Dhruv-C", "name": { "family": "Desai", "given": "Dhruv C." } }, { "id": "Zviazhynski-Bahdan", "name": { "family": "Zviazhynski", "given": "Bahdan" }, "orcid": "0000-0002-3862-8093" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Magnetotransport in semiconductors and two-dimensional materials from first principles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Physical Society. \n\nReceived 19 January 2021; revised 22 March 2021; accepted 23 March 2021; published 7 April 2021. \n\nThis work was supported by the National Science Foundation under Grant No. DMR-1750613. J.-J.Z. acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The development of some computational methods employed in this work was supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility located at Lawrence Berkeley National Laboratory, operated under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevB.103.L161103.pdf
Submitted - 2101.06457.pdf
", "abstract": "We demonstrate a first-principles method to study magnetotransport in materials by solving the Boltzmann transport equation (BTE) in the presence of an external magnetic field. Our approach employs ab initio electron-phonon interactions and takes spin-orbit coupling into account. We apply our method to various semiconductors (Si and GaAs) and two-dimensional (2D) materials (graphene) as representative case studies. The magnetoresistance, Hall mobility, and Hall factor in Si and GaAs are in very good agreement with experiments. In graphene, our method predicts a large magnetoresistance, consistent with experiments. Analysis of the steady-state electron occupations in graphene shows the dominant role of optical phonon scattering and the breaking of the relaxation time approximation. Our paper provides a detailed understanding of the microscopic mechanisms governing magnetotransport coefficients, establishing the BTE in a magnetic field as a broadly applicable first-principles tool to investigate transport in semiconductors and 2D materials.", "date": "2021-04-15", "date_type": "published", "publication": "Physical Review B", "volume": "103", "number": "16", "publisher": "American Physical Society", "pagerange": "Art. No. L161103", "id_number": "CaltechAUTHORS:20210210-082533037", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210210-082533037", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevB.103.L161103", "primary_object": { "basename": "2101.06457.pdf", "url": "https://authors.library.caltech.edu/records/p9s5b-en862/files/2101.06457.pdf" }, "related_objects": [ { "basename": "PhysRevB.103.L161103.pdf", "url": "https://authors.library.caltech.edu/records/p9s5b-en862/files/PhysRevB.103.L161103.pdf" } ], "pub_year": "2021", "author_list": "Desai, Dhruv C.; Zviazhynski, Bahdan; et el." }, { "id": "https://authors.library.caltech.edu/records/vvx94-7ry60", "eprint_id": 108073, "eprint_status": "archive", "datestamp": "2023-10-03 22:36:51", "lastmod": "2023-10-24 15:31:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ozden-Adnan", "name": { "family": "Ozden", "given": "Adnan" }, "orcid": "0000-0002-6924-1967" }, { "id": "Wang-Yuhang", "name": { "family": "Wang", "given": "Yuhang" }, "orcid": "0000-0001-5336-5183" }, { "id": "Li-Fengwang", "name": { "family": "Li", "given": "Fengwang" }, "orcid": "0000-0003-1531-2966" }, { "id": "Luo-Mingchuan", "name": { "family": "Luo", "given": "Mingchuan" } }, { "id": "Sisler-Jared", "name": { "family": "Sisler", "given": "Jared" } }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Burdyny-Thomas", "name": { "family": "Burdyny", "given": "Thomas" } }, { "id": "Lum-Yanwei", "name": { "family": "Lum", "given": "Yanwei" } }, { "id": "Yadegari-Hossein", "name": { "family": "Yadegari", "given": "Hossein" } }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Sargent-Edward-H", "name": { "family": "Sargent", "given": "Edward H." }, "orcid": "0000-0003-0396-6495" }, { "id": "Sinton-David", "name": { "family": "Sinton", "given": "David" }, "orcid": "0000-0003-2714-6408" } ] }, "title": "Cascade CO\u2082 electroreduction enables efficient carbonate-free production of ethylene", "ispublished": "pub", "full_text_status": "public", "keywords": "CO electroreduction; carbon utilization; ethylene electrolysis; electrolyser; membrane electrode assembly; solid-oxide electrolyser; catalyst design; molecular catalyst; energy efficiency", "note": "\u00a9 2021 Elsevier. \n\nReceived 19 October 2020, Revised 1 December 2020, Accepted 21 January 2021, Available online 15 February 2021. \n\nThe authors acknowledge Ontario Centre for the Characterization of Advanced Materials (OCCAM) for sample preparation and characterization facilities. Funding: this work received financial support from the Ontario Research Foundation: Research Excellence Program, the Natural Sciences and Engineering Research Council (NSERC) of Canada, the CIFAR Bio-Inspired Solar Energy program and TOTAL S.E. and the Joint Centre of Artificial Synthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE-SC0004993. D.S. acknowledges the NSERC E.W.R Steacie Memorial Fellowship. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). The authors thank Dr. Y.-F. Liao for the GIWAXS measurements at Spring-8 BL-12B2 beamline of NSRRC. The authors also thank Dr. T. Regier for their assistance at the SGM beamline of CLS. \n\nAuthor contributions. D.S. and E.H.S. supervised the project. A.O. carried out all the electrochemical experiments with advice from Y.W. and F.L. A.T., A.R.-H., J.C.P., and T.A. designed and synthesized the N-tolylpyridinium molecule and contributed to the manuscript editing. A.O. and F.L. carried out Raman spectroscopies. Y.W. performed the SEM and TEM analysis. A.O. performed the nuclear magnetic resonance spectroscopies. A.O. and Y.W. co-wrote the manuscript. J.S. performed the TEA modeling. T.B. conducted the CO diffusion modeling. M.L., Y.L., and H.Y. contributed to the discussions and manuscript editing. A.O., Y.W., and F.L. provided equal contributions to this study. All authors contributed to the manuscript. \n\nDeclaration of interests. A.O., Y.W., F.L., D.S., and E.H.S. have filled provisional patent application no. 63/135,277 regarding Cascade CO2 electroreduction systems.\n\nSubmitted - Manuscript-Joule.docx
Supplemental Material - 1-s20-S2542435121000386-mmc1.pdf
", "abstract": "CO\u2082 electroreduction provides a route to convert waste emissions into chemicals such as ethylene (C\u2082H\u2084). However, the direct transformation of CO\u2082-to-C\u2082H\u2084 suffers from CO\u2082 loss to carbonate, consuming up to 72% of energy input. A cascade approach\u2014coupling a solid-oxide CO\u2082-to-CO electrochemical cell (SOEC) with a CO-to-C\u2082H\u2084 membrane electrode assembly (MEA)\u2014would eliminate CO\u2082 loss to carbonate. However, this approach requires a CO-to-C\u2082H\u2084 MEA with energy efficiency well beyond demonstrations to date. Focusing on the MEA, we find that an N-tolyl substituted tetrahydro-bipyridine film improves the stabilization of key reaction intermediates, while an SSC ionomer enhances CO transport to the Cu surface, enabling a C\u2082H\u2084 faradaic efficiency of 65% at 150 mA cm\u207b\u00b2 for 110 h. Demonstrating a cascade SOEC-MEA approach, we achieve CO\u2082-to-C\u2082H\u2084 with a ~48% reduction in energy intensity compared with the direct route. We further reduce the energy intensity by coupling CO electroreduction (CORR) with glucose electrooxidation.", "date": "2021-03-17", "date_type": "published", "publication": "Joule", "volume": "5", "number": "3", "publisher": "Cell Press", "pagerange": "706-719", "id_number": "CaltechAUTHORS:20210216-140504601", "issn": "2542-4351", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210216-140504601", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ontario Research Foundation" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "TOTAL" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.joule.2021.01.007", "primary_object": { "basename": "Manuscript-Joule.docx", "url": "https://authors.library.caltech.edu/records/vvx94-7ry60/files/Manuscript-Joule.docx" }, "related_objects": [ { "basename": "1-s20-S2542435121000386-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/vvx94-7ry60/files/1-s20-S2542435121000386-mmc1.pdf" } ], "pub_year": "2021", "author_list": "Ozden, Adnan; Wang, Yuhang; et el." }, { "id": "https://authors.library.caltech.edu/records/qnbck-nr932", "eprint_id": 108223, "eprint_status": "archive", "datestamp": "2023-08-20 02:12:25", "lastmod": "2023-10-23 16:33:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Operando Electrochemical Spectroscopy for CO on Cu(100) at pH 1 to 13: Validation of Grand Canonical Potential Predictions", "ispublished": "pub", "full_text_status": "public", "keywords": "operando electrochemical PMIRS, density functional theory, GCP, operando CO vibration frequencies", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: December 18, 2020; Revised: February 8, 2021; Published: February 24, 2021. \n\nThe invaluable contributions of Prof. Manuel P. Soriaga on the seriatim implementation of operando analytical protocols for CO\u2082 reduction studies are gratefully acknowledged. Manny passed away on July 17, 2019 and will always be missed in the electrochemical surface science community. The experimental portion of this paper is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The computational studies were initiated with JCAP funding, but the final results in the figures are based on work performed by the Liquid Sunlight Alliance, which is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under Award Number DE-SC0021266. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a U.S. Department of Energy Office of Science User Facility operated under Contract No. DE-AC02-05CH11231. \n\nJ.H.B. and S.K. first authorship is equally shared. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs0c05564_si_001.pdf
Supplemental Material - cs0c05564_si_002.zip
", "abstract": "Electrochemical reduction of CO\u2082 to value-added products is an attractive strategy to address issues of increasing atmospheric CO\u2082 concentration. Cu is the only pure metal catalyst known to electrochemically convert CO\u2082 to appreciable amounts of oxygenates and hydrocarbons such as C\u2082H\u2085OH, CH\u2084, and C\u2082H\u2084, but the Faraday efficiencies are too low and the onset potentials are too high. To discover electrocatalytic systems better than Cu, we use in silico strategies based on new grand canonical potential (GCP) methods, but the complexity of the electrode\u2013electrolyte interface makes it difficult to validate the accuracy of GCP. Operando electrochemical polarization-modulation infrared spectroscopy (PMIRS) provides a performance benchmark for theoretical tools that account for the vibrational stretching frequencies of surface-bound CO, \u03bd_(CO), as a function of pH and applied potential U. We show here that GCP calculations of the surface coverages of H*, OH*, and CO* on Cu(100) as a function of U lead to excellent predictions of the potential-dependent \u03bd_(CO) and its shift with pH from 1 to 13. This validation justifies the use of GCP for predicting the performance of catalyst designs.", "date": "2021-03-05", "date_type": "published", "publication": "ACS Catalysis", "volume": "11", "number": "5", "publisher": "American Chemical Society", "pagerange": "3173-3181", "id_number": "CaltechAUTHORS:20210225-152852499", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210225-152852499", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1411", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.0c05564", "primary_object": { "basename": "cs0c05564_si_001.pdf", "url": "https://authors.library.caltech.edu/records/qnbck-nr932/files/cs0c05564_si_001.pdf" }, "related_objects": [ { "basename": "cs0c05564_si_002.zip", "url": "https://authors.library.caltech.edu/records/qnbck-nr932/files/cs0c05564_si_002.zip" } ], "pub_year": "2021", "author_list": "Baricuatro, Jack H.; Kwon, Soonho; et el." }, { "id": "https://authors.library.caltech.edu/records/jpz1d-m4m65", "eprint_id": 108087, "eprint_status": "archive", "datestamp": "2023-08-20 02:08:35", "lastmod": "2023-10-23 16:27:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Finke-Cody-E", "name": { "family": "Finke", "given": "Cody E." }, "orcid": "0000-0002-1343-1737" }, { "id": "Leandri-Hugo-F", "name": { "family": "Leandri", "given": "Hugo F." } }, { "id": "Karumb-Evody-Tshijik", "name": { "family": "Karumb", "given": "Evody Tshijik" } }, { "id": "Zheng-David", "name": { "family": "Zheng", "given": "David" } }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" }, { "id": "Fromer-Neil-A", "name": { "family": "Fromer", "given": "Neil A." } } ] }, "title": "Economically advantageous pathways for reducing greenhouse gas emissions from industrial hydrogen under common, current economic conditions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 The Royal Society of Chemistry. \n\nSubmitted 01 Dec 2020; Accepted 03 Feb 2021; First published 15 Feb 2021.\n\nSupporting data referenced above may be found in the ESI. This work was supported by the Department of Energy's Advanced Manufacturing Office Cyclotron Road Program. Funding was provided to C. E. F., H. F. L., and N. A. F., by the Resnick Sustainability Institute at Caltech. In part, this material is based upon work by C. E. F., E. T. K. and H. F. L. performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. C. E. F. was the primary concept generator and modeler for this work. H. F. L. performed the electrochemistry. D. Z. developed early versions of the model. N. A. F. aided in idea development. C. E. F., H. F. L., E. T. K., M. R. H., and N. A. F. prepared the manuscript and helped with its reviewing. All authors reviewed and contributed to the final manuscript. We are grateful to Fanfei Li for helping acquire techno-economic data and Prof. Jess Adkins at Caltech for being willing to relentlessly talk shop with us. \n\nConflicts of interest: H. F. L., D. Z., M. R. H., and N. A. F.'s institution (California Institute of Technology) has filed a U.S. patent application directly relating to the work described in the paper (patent application no. US20190376191A1, filed on May. 17, 2019). C. E. F., H. L., and E. T. K. are founders or employees of Brimstone Energy Inc., a company which has hydrogen cogeneration in its vision.\n\nSupplemental Material - d0ee03768k11.pdf
", "abstract": "Hydrogen is a major industrial chemical whose manufacture is responsible for \u223c3% of global carbon dioxide emissions. >95% of hydrogen is made via reforming fossil fuels which typically co-produces hydrogen and waste carbon dioxide. Nearly all other hydrogen is co-produced with other commodity chemicals. Unfortunately, many alternative, clean hydrogen production processes are small-scale because they require major reductions in capital cost or energy prices to be economical enough for industry. Because the climate problem is urgent, and the economics of future energy is uncertain, this paper seeks to expand the options for producing industrial-scale, clean hydrogen under common, present-day economic conditions. First, we build a model to understand the economic and carbon dioxide emissions constraints of sulfur electrolysis which is an emerging process that cogenerates hydrogen and co-salable sulfuric acid and has the potential to produce up to 36% of the world's current hydrogen demand under present-day, average US economic conditions. We also use our model to evaluate water electrolysis, which cogenerates hydrogen and waste oxygen, but is not economical under present-day average US economic conditions. We then propose criteria for identifying clean hydrogen production chemistries. Using these criteria, we find enough reactions to have the combined potential to make over 150% of the world's industrial hydrogen needs under present-day, average US economic conditions while reducing cost and reducing or eliminating CO\u2082 emissions. Given the urgency of the climate problem, we believe that an economic analysis, such as this is crucial to near-term CO\u2082 emissions reductions.", "date": "2021-03-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "14", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "1517-1529", "id_number": "CaltechAUTHORS:20210217-100658347", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210217-100658347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d0ee03768k", "primary_object": { "basename": "d0ee03768k11.pdf", "url": "https://authors.library.caltech.edu/records/jpz1d-m4m65/files/d0ee03768k11.pdf" }, "pub_year": "2021", "author_list": "Finke, Cody E.; Leandri, Hugo F.; et el." }, { "id": "https://authors.library.caltech.edu/records/gq5ga-cqh54", "eprint_id": 108107, "eprint_status": "archive", "datestamp": "2023-08-20 01:57:58", "lastmod": "2023-10-23 16:28:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Hongyan", "name": { "family": "Jiang", "given": "Hongyan" }, "orcid": "0000-0003-3559-2774" }, { "id": "Tao-Xuecheng", "name": { "family": "Tao", "given": "Xuecheng" }, "orcid": "0000-0003-2907-3839" }, { "id": "Kammler-Marvin", "name": { "family": "Kammler", "given": "Marvin" } }, { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Wodtke-Alec-M", "name": { "family": "Wodtke", "given": "Alec M." }, "orcid": "0000-0002-6509-2183" }, { "id": "Kandratsenka-Alexander", "name": { "family": "Kandratsenka", "given": "Alexander" }, "orcid": "0000-0003-2132-1957" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "B\u00fcnermann-Oliver", "name": { "family": "B\u00fcnermann", "given": "Oliver" }, "orcid": "0000-0001-9837-6548" } ] }, "title": "Small Nuclear Quantum Effects in Scattering of H and D from Graphene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: September 24, 2020; Accepted: February 10, 2021; Published: February 17, 2021. \n\nX.T. acknowledges support from the Department of Dynamics at Surfaces at the MPI for Biophysical Chemistry and ICASEC at the University of Goettingen during the visit. H.J., O.B., and A.M.W. acknowledge support the from the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation, 217133147/SFB 1073, project A04) and financial support from the Ministerium f\u00fcr Wissenschaft und Kultur (MWK) Niedersachsen and the Volkswagenstiftung under grant no. INST 186/902-1 to build the experimental apparatus. A.M.W., M.K., and A.K. also acknowledge the Max Planck Society for the Advancement of Science. F.D. and T.F.M. acknowledge that this material is based on work performed by the Joint Center for Artificial Photosynthesis, a U.S. Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under award DE-SC0004993; X.T. and T.F.M. acknowledge support from the DOE (DE-SC0019390) and also thank the National Energy Research Scientific Computing Center for the computational resources. We thank Dan Auerbach and Dirk Schwarzer for helpful discussions. \n\nAuthor Contributions: H.J. and X.T. contributed equally to this work. \n\nThe authors declare the following competing financial interest(s): Calculations performed in this work use the Entos Qcore simulation software, and Thomas Miller is a co-founder Entos, Inc.\n\nSupplemental Material - jz0c02933_si_001.pdf
", "abstract": "We study nuclear quantum effects in H/D sticking to graphene, comparing scattering experiments at near-zero coverage with classical, quantized, and transition-state calculations. The experiment shows H/D sticking probabilities that are indistinguishable from one another and markedly smaller than those expected from a consideration of zero-point energy shifts of the chemisorption transition state. Inclusion of dynamical effects and vibrational anharmonicity via ring-polymer molecular dynamics (RPMD) yields results that are in good agreement with the experimental results. RPMD also reveals that nuclear quantum effects, while modest, arise primarily from carbon and not from H/D motion, confirming the importance of a C atom rehybridization mechanism associated with H/D sticking on graphene.", "date": "2021-02-25", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "12", "number": "7", "publisher": "American Chemical Society", "pagerange": "1991-1996", "id_number": "CaltechAUTHORS:20210218-150439555", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210218-150439555", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of G\u00f6ttingen" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "217133147/SFB 1073" }, { "agency": "Ministerium f\u00fcr Wissenschaft und Kultur (MWK) Niedersachsen" }, { "agency": "Volkswagenstiftung", "grant_number": "INST 186/902-1" }, { "agency": "Max Planck Society" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019390" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.0c02933", "primary_object": { "basename": "jz0c02933_si_001.pdf", "url": "https://authors.library.caltech.edu/records/gq5ga-cqh54/files/jz0c02933_si_001.pdf" }, "pub_year": "2021", "author_list": "Jiang, Hongyan; Tao, Xuecheng; et el." }, { "id": "https://authors.library.caltech.edu/records/a5aa5-x0s63", "eprint_id": 108057, "eprint_status": "archive", "datestamp": "2023-08-20 01:57:26", "lastmod": "2023-10-23 16:26:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Jianchun", "name": { "family": "Wang", "given": "Jianchun" }, "orcid": "0000-0002-3998-8699" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Fenwick-Aidan-Q", "name": { "family": "Fenwick", "given": "Aidan Q." }, "orcid": "0000-0003-4442-0878" }, { "id": "Baroud-Turki-N", "name": { "family": "Baroud", "given": "Turki N." }, "orcid": "0000-0001-6430-9128" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Ko-Jeong-Hoon", "name": { "family": "Ko", "given": "Jeong Hoon" }, "orcid": "0000-0003-2000-3789" }, { "id": "Gan-Quan", "name": { "family": "Gan", "given": "Quan" }, "orcid": "0000-0001-5908-4163" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard III", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Selective CO\u2082 Electrochemical Reduction Enabled by a Tricomponent Copolymer Modifier on a Copper Surface", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrocatalysis, Selectivity, Electrodes, Polymers, Copolymers", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: November 30, 2020; Published: February 11, 2021. \n\nThis research benefited from the use of instrumentation made available by the Caltech CCE Multiuser Mass Spectrometry Laboratory. XPS data were collected at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. Nick Watkins is thanked for assistance with SEM experiments. Dr. Shunsuke Sato, Dr. Brendon J. McNicholas, and Dr. Yan Xu are thanked for their discussions. \n\nThis study was supported by the King Fahd University of Petroleum and Minerals (R.H.G.) and the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja0c12478_si_001.pdf
", "abstract": "Electrochemical CO\u2082 reduction over Cu could provide value-added multicarbon hydrocarbons and alcohols. Despite recent breakthroughs, it remains a significant challenge to design a catalytic system with high product selectivity. Here we demonstrate that a high selectivity of ethylene (55%) and C\u2082\u208a products (77%) could be achieved by a highly modular tricomponent copolymer modified Cu electrode, rivaling the best performance using other modified polycrystalline Cu foil catalysts. Such a copolymer can be conveniently prepared by a ring-opening metathesis polymerization, thereby offering a new degree of freedom for tuning the selectivity. Control experiments indicate all three components are essential for the selectivity enhancement. A surface characterization showed that the incorporation of a phenylpyridinium component increased the film robustness against delamination. It was also shown that its superior performance is not due to a morphology change of the Cu underneath. Molecular dynamics (MD) simulations indicate that a combination of increased local CO\u2082 concentration, increased porosity for gas diffusion, and the local electric field effect together contribute to the increased ethylene and C\u2082\u208a product selectivity.", "date": "2021-02-24", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "143", "number": "7", "publisher": "American Chemical Society", "pagerange": "2857-2865", "id_number": "CaltechAUTHORS:20210216-080252695", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210216-080252695", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "King Fahd University of Petroleum and Minerals (KFUPM)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1417", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.0c12478", "primary_object": { "basename": "ja0c12478_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a5aa5-x0s63/files/ja0c12478_si_001.pdf" }, "pub_year": "2021", "author_list": "Wang, Jianchun; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/8z5cx-46068", "eprint_id": 107416, "eprint_status": "archive", "datestamp": "2023-08-22 08:36:51", "lastmod": "2023-10-23 15:52:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kennedy-Kathleen-M", "name": { "family": "Kennedy", "given": "Kathleen M." }, "orcid": "0000-0002-7125-4871" }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul Andrew" }, "orcid": "0000-0003-3909-1790" }, { "id": "Cab\u00e1n-Acevedo-Miguel", "name": { "family": "Cab\u00e1n-Acevedo", "given": "Miguel" }, "orcid": "0000-0003-0054-8044" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Primary Corrosion Processes for Polymer-Embedded Free-Standing or Substrate-Supported Silicon Microwire Arrays in Aqueous Alkaline Electrolytes", "ispublished": "pub", "full_text_status": "public", "keywords": "microwires; corrosion; solar fuels; membrane-embedded", "note": "\u00a9 2021 American Chemical Society. \n\nReceived: October 27, 2020; Revised: December 18, 2020; Published: January 6, 2021. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy-Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We gratefully acknowledge the critical support and infrastructure provided for this work by the Kavli Nanoscience Institute at Caltech. \n\nAuthor Contributions: K.M.K. and P.K. conceived the idea and designed the study. P.K. fabricated the microwire arrays and contributed to figure design. K.M.K. performed the corrosion experiments, optical and SEM characterization, and wrote the text. M.C.A. performed the FIB studies and contributed substantially to the intellectual understanding of the corrosion process. K.M.P. wrote the Matlab code used to analyze the optical images and generate statistics. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nl0c04298_si_001.pdf
", "abstract": "Solar fuel devices have shown promise as a sustainable source of chemical fuels. However, long-term stability of light absorbing materials remains a substantial barrier to practical devices. Herein, multiple corrosion pathways in 1 M KOH(aq) have been defined for TiO\u2082-protected Si microwire arrays in a polymer membrane either attached to a substrate or free-standing. Top-down corrosion was observed in both morphologies through defects in the TiO\u2082 coating. For the substrate-based samples, bottom-up corrosion was observed through the substrate and up the adjacent wires. In the free-standing samples, uniform bottom-up corrosion was observed through the membrane with all wire material corroded within 10 days of immersion in the dark in 1 M KOH(aq).", "date": "2021-01-27", "date_type": "published", "publication": "Nano Letters", "volume": "21", "number": "2", "publisher": "American Chemical Society", "pagerange": "1056-1061", "id_number": "CaltechAUTHORS:20210112-091401361", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210112-091401361", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.nanolett.0c04298", "primary_object": { "basename": "nl0c04298_si_001.pdf", "url": "https://authors.library.caltech.edu/records/8z5cx-46068/files/nl0c04298_si_001.pdf" }, "pub_year": "2021", "author_list": "Kennedy, Kathleen M.; Kempler, Paul Andrew; et el." }, { "id": "https://authors.library.caltech.edu/records/qz1zk-egz88", "eprint_id": 106496, "eprint_status": "archive", "datestamp": "2023-08-20 01:29:06", "lastmod": "2023-10-20 23:33:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Banin-U", "name": { "family": "Banin", "given": "U." }, "orcid": "0000-0003-1698-2128" }, { "id": "Waiskopf-N", "name": { "family": "Waiskopf", "given": "N" } }, { "id": "Hammarstr\u00f6m-L", "name": { "family": "Hammarstr\u00f6m", "given": "L." }, "orcid": "0000-0002-9933-9084" }, { "id": "Boschloo-G", "name": { "family": "Boschloo", "given": "G." } }, { "id": "Freitag-M", "name": { "family": "Freitag", "given": "M." } }, { "id": "Johansson-E-M-J", "name": { "family": "Johansson", "given": "E. M. J." } }, { "id": "S\u00e1-J", "name": { "family": "S\u00e1", "given": "J." }, "orcid": "0000-0003-2124-9510" }, { "id": "Tian-Haining", "name": { "family": "Tian", "given": "H." }, "orcid": "0000-0001-6897-2808" }, { "id": "Johnston-M-B", "name": { "family": "Johnston", "given": "M. B." }, "orcid": "0000-0002-0301-8033" }, { "id": "Herz-L-M", "name": { "family": "Herz", "given": "L. M." }, "orcid": "0000-0001-9621-334X" }, { "id": "Milot-R-L", "name": { "family": "Milot", "given": "R. L." } }, { "id": "Kanatzidis-M-G", "name": { "family": "Kanatzidis", "given": "M. G." }, "orcid": "0000-0003-2037-4168" }, { "id": "Ke-W", "name": { "family": "Ke", "given": "W." } }, { "id": "Spanopoulos-I", "name": { "family": "Spanopoulos", "given": "I." } }, { "id": "Kohlstedt-K-L", "name": { "family": "Kohlstedt", "given": "K. L." }, "orcid": "0000-0001-8045-0930" }, { "id": "Schatz-G-C", "name": { "family": "Schatz", "given": "G. C." }, "orcid": "0000-0001-5837-4740" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "N." }, "orcid": "0000-0001-5245-0538" }, { "id": "Meyer-T", "name": { "family": "Meyer", "given": "T." }, "orcid": "0000-0002-7006-2608" }, { "id": "Nozik-A-J", "name": { "family": "Nozik", "given": "A. J." }, "orcid": "0000-0001-7176-7645" }, { "id": "Beard-M-C", "name": { "family": "Beard", "given": "M. C." }, "orcid": "0000-0002-2711-1355" }, { "id": "Armstrong-F", "name": { "family": "Armstrong", "given": "F." }, "orcid": "0000-0001-8041-2491" }, { "id": "Megarity-C-F", "name": { "family": "Megarity", "given": "C. F." } }, { "id": "Schmuttenmaer-C-A", "name": { "family": "Schmuttenmaer", "given": "C. A." }, "orcid": "0000-0001-9992-8578" }, { "id": "Batista-V-S", "name": { "family": "Batista", "given": "V. S." }, "orcid": "0000-0002-3262-1237" }, { "id": "Brudvig-G-W", "name": { "family": "Brudvig", "given": "G. W." }, "orcid": "0000-0002-7040-1892" } ] }, "title": "Nanotechnology for catalysis and solar energy conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Author(s). Published by IOP Publishing Ltd.\nOriginal content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 11 May 2020; Revised 11 September 2020; Accepted 30 September 2020; Published 5 November 2020. \n\nThis work was supported by the Israel Science Foundation (Grant No. 1867/17). U B thanks the Alfred & Erica Larisch memorial chair. \n\nThis work was supported by ONR Grant N00014-20-1-2725. \n\nThe authors acknowledge the support by the Center for Light Energy Activated Redox Processes (LEAP) Energy Frontier Research Center under the award DE-SC0001059. \n\nThe Department of Energy, Office of Basic Energy Sciences, grant DE-FG02-03ER15483, and the Department of Energy, Office of Science, through the Joint Center for Artificial Photosynthesis, award SC-0004993, are acknowledged for support that made preparation of this manuscript possible. \n\nSupport from the Solar Photochemistry program within the Division of Chemical Sciences, Geosciences, and Biosciences in the Office of Basic Energy of the Department of Energy is acknowledged. DOE funding was provided to NREL through Contract DE-AC36-086038308. \n\nC F M and F A A are supported by a grant (CF 327) from the EPA Cephalosporin Fund.\n\nPublished - Banin_2021_Nanotechnology_32_042003.pdf
", "abstract": "This roadmap on Nanotechnology for Catalysis and Solar Energy Conversion focuses on the application of nanotechnology in addressing the current challenges of energy conversion: 'high efficiency, stability, safety, and the potential for low-cost/scalable manufacturing' to quote from the contributed article by Nathan Lewis. This roadmap focuses on solar-to-fuel conversion, solar water splitting, solar photovoltaics and bio-catalysis. It includes dye-sensitized solar cells (DSSCs), perovskite solar cells, and organic photovoltaics. Smart engineering of colloidal quantum materials and nanostructured electrodes will improve solar-to-fuel conversion efficiency, as described in the articles by Waiskopf and Banin and Meyer. Semiconductor nanoparticles will also improve solar energy conversion efficiency, as discussed by Boschloo et al in their article on DSSCs. Perovskite solar cells have advanced rapidly in recent years, including new ideas on 2D and 3D hybrid halide perovskites, as described by Spanopoulos et al 'Next generation' solar cells using multiple exciton generation (MEG) from hot carriers, described in the article by Nozik and Beard, could lead to remarkable improvement in photovoltaic efficiency by using quantization effects in semiconductor nanostructures (quantum dots, wires or wells). These challenges will not be met without simultaneous improvement in nanoscale characterization methods. Terahertz spectroscopy, discussed in the article by Milot et al is one example of a method that is overcoming the difficulties associated with nanoscale materials characterization by avoiding electrical contacts to nanoparticles, allowing characterization during device operation, and enabling characterization of a single nanoparticle. Besides experimental advances, computational science is also meeting the challenges of nanomaterials synthesis. The article by Kohlstedt and Schatz discusses the computational frameworks being used to predict structure\u2013property relationships in materials and devices, including machine learning methods, with an emphasis on organic photovoltaics. The contribution by Megarity and Armstrong presents the 'electrochemical leaf' for improvements in electrochemistry and beyond. In addition, biohybrid approaches can take advantage of efficient and specific enzyme catalysts. These articles present the nanoscience and technology at the forefront of renewable energy development that will have significant benefits to society.", "date": "2021-01-22", "date_type": "published", "publication": "Nanotechnology", "volume": "32", "number": "4", "publisher": "IOP", "pagerange": "Art. No. 042003", "id_number": "CaltechAUTHORS:20201106-130122089", "issn": "0957-4484", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201106-130122089", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Israel Science Foundation", "grant_number": "1867/17" }, { "agency": "Alfred and Erica Larisch memorial chair" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-20-1-2725" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001059" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-086038308" }, { "agency": "EPA Cephalosporin Fund", "grant_number": "CF 327" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1088/1361-6528/abbce8", "primary_object": { "basename": "Banin_2021_Nanotechnology_32_042003.pdf", "url": "https://authors.library.caltech.edu/records/qz1zk-egz88/files/Banin_2021_Nanotechnology_32_042003.pdf" }, "pub_year": "2021", "author_list": "Banin, U.; Waiskopf, N; et el." }, { "id": "https://authors.library.caltech.edu/records/zaj0j-qem58", "eprint_id": 107175, "eprint_status": "archive", "datestamp": "2023-08-20 01:21:38", "lastmod": "2023-10-23 15:37:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shen-Xin", "name": { "family": "Shen", "given": "Xin" } }, { "id": "Yao-Maoqing", "name": { "family": "Yao", "given": "Maoqing" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Zhao-Tianshuo", "name": { "family": "Zhao", "given": "Tianshuo" } }, { "id": "He-Yulian", "name": { "family": "He", "given": "Yulian" } }, { "id": "Chi-Chun-Yung", "name": { "family": "Chi", "given": "Chun-Yung" } }, { "id": "Zhou-Chongwu", "name": { "family": "Zhou", "given": "Chongwu" }, "orcid": "0000-0001-8448-8450" }, { "id": "Dapkus-Paul-D", "name": { "family": "Dapkus", "given": "Paul Daniel" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" } ] }, "title": "Defect-Tolerant TiO\u2082-Coated and Discretized Photoanodes for >600 h of Stable Photoelectrochemical Water Oxidation", "ispublished": "pub", "full_text_status": "public", "keywords": "Photonics, Oxides, Absorption, Nanowires, Gallium arsenide", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: December 3, 2020; Accepted: December 9, 2020; Published: December 16, 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and under Award Number DE-SC0001013 to the Center for Energy Nanoscience, an Energy Frontier Research Center (EFRC). We thank the Materials Characterization Core at Yale West Campus for SEM characterization. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c02521_si_001.pdf
", "abstract": "Arrays of GaAs nanowires have been grown by selective-area metal\u2013organic chemical-vapor deposition (MOCVD) onto photoactive planar Si substrates. This tandem, vertical-wire-array-on-planar absorber was then coated by atomic layer deposition (ALD) of an amorphous TiO\u2082 (a-TiO\u2082) stabilization layer, followed by deposition of a NiO_x electrocatalyst layer. The tandem planar Si/nanowire GaAs/a-TiO\u2082/NiO_x photoanodes exhibited continuous solar-driven water oxidation in 1.0 M KOH(aq) for over 600 h without substantial photocurrent decay. The preservation of the nanowire morphology and structural integrity during >600 h of photoanodic operation confirms the benefits of mitigating and isolating nanoscale defects via the architecture of discretized absorbers on a self-passivating and insulating substrate. Nanoscale morphology and compositions of the photoanode after 600 h of testing were characterized to reveal the self-limiting corrosion behavior. It provides a promising approach to develop efficient but otherwise unstable absorbers such as III\u2013V materials into defect-tolerant, corrosion-resistant photoanodes.", "date": "2021-01-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "6", "number": "1", "publisher": "American Chemical Society", "pagerange": "193-200", "id_number": "CaltechAUTHORS:20201217-143607686", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201217-143607686", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001013" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.0c02521", "primary_object": { "basename": "nz0c02521_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zaj0j-qem58/files/nz0c02521_si_001.pdf" }, "pub_year": "2021", "author_list": "Shen, Xin; Yao, Maoqing; et el." }, { "id": "https://authors.library.caltech.edu/records/r32c1-ssf59", "eprint_id": 106934, "eprint_status": "archive", "datestamp": "2023-08-22 08:25:12", "lastmod": "2023-10-23 15:11:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Chen-Yalu", "name": { "family": "Chen", "given": "Yalu" }, "orcid": "0000-0002-0589-845X" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Artificial Intelligence and QM/MM with a Polarizable Reactive Force Field for Next-Generation Electrocatalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "machine learning; quantum mechanics; polarizable reactive force field; explicit solvent; vibrational frequency; catalyst; electrocatalysis; nanoparticles", "note": "\u00a9 2020 Published by Elsevier Inc. \n\nReceived 17 May 2020, Revised 28 July 2020, Accepted 6 November 2020, Available online 27 November 2020. \n\nWe thank the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993 and the Computational Materials Sciences Program funded by the US Department of Energy, Office of Science, Basic Energy Sciences, under award number DE-SC00014607. Although JCAP funded most of the calculations, the machine learning application was funded by the Liquid Sunlight Alliance (LiSA), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0021266. The calculations were carried out on the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. \n\nAuthor Contributions: S.N. and W.A.G. designed research. S.N. and Y.C. performed the calculations. S.N., Y.C., and W.A.G. analyzed data. S.N. and W.A.G. wrote the paper. S.K. and H.X. provided some data and programming scripts that were used in this research. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 1-s2.0-S2590238520306275-mmc1.pdf
", "abstract": "To develop new generations of electrocatalysts, we need the accuracy of full explicit solvent quantum mechanics (QM) for practical-sized nanoparticles and catalysts. To do this, we start with the RexPoN reactive force field that provides higher accuracy than density functional theory (DFT) for water and combine it with QM to accurately include long-range interactions and polarization effects to enable reactive simulations with QM accuracy in the presence of explicit solvent. We apply this RexPoN-embedded QM (ReQM) to reactive simulations of electrocatalysis, demonstrating that ReQM accurately replaces DFT water for computing the Raman frequencies of reaction intermediates during CO\u2082 reduction to ethylene. Then, we illustrate the power of this approach by combining with machine learning to predict the performance of about 10,000 surface sites and identify the active sites of solvated gold (Au) nanoparticles and dealloyed Au surfaces. This provides an accurate but practical way to design high-performance electrocatalysts.", "date": "2021-01-06", "date_type": "published", "publication": "Matter", "volume": "4", "number": "1", "publisher": "Cell Press", "pagerange": "195-216", "id_number": "CaltechAUTHORS:20201204-185233484", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201204-185233484", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0021266" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1403", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2020.11.010", "primary_object": { "basename": "1-s2.0-S2590238520306275-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/r32c1-ssf59/files/1-s2.0-S2590238520306275-mmc1.pdf" }, "pub_year": "2021", "author_list": "Naserifar, Saber; Chen, Yalu; et el." }, { "id": "https://authors.library.caltech.edu/records/np129-58b77", "eprint_id": 106813, "eprint_status": "archive", "datestamp": "2023-08-20 01:19:34", "lastmod": "2023-10-20 23:49:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." } }, { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Optical and electrochemical effects of H\u2082 and O\u2082 bubbles at upward-facing Si photoelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 31 Aug 2020; Accepted 12 Nov 2020; First published\t12 Nov 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. Silicon microwire arrays were fabricated in the Kavli Nanoscience Institute (KNI) at Caltech; we thank the KNI staff for their assistance with fabrication. We are grateful to Rick Gerhart for assistance in fabricating glassware for solar simulations. Additional instrumentation was provided by the Molecular Materials Research Center in the Beckman Institute at Caltech. We appreciate Bruce Brunschwig for providing helpful feedback on the manuscript. \n\nAuthor contributions: Si-\u03bcW Fabrication, P. A. K., Metallization, Z. P. I., Atomic Layer Deposition, W. Y., Scanning-Electron Microscopy, A. I. C., Investigation, P. A. K.; Writing \u2013 Original Draft, P. A. K. and N. S. L., Writing \u2013 Review and Editing, P. A. K., N. S. L., Z. P. I., W. Y., A. I. C., Funding Acquisition, N. S. L. Supervision, N. S. L. \n\nThe authors declare no competing interests.\n\nSupplemental Material - d0ee02796k1.pdf
Supplemental Material - d0ee02796k2.mp4
Supplemental Material - d0ee02796k3.mp4
", "abstract": "The effects of the size, contact-angle, and coverage of gas bubbles on solar fuels devices were characterized at cm-scale, upward-facing planar and microwire-array Si photoelectrodes in stagnant electrolytes. Experimental measurements were supported by ray-tracing simulations of surface attached gas bubble films. A dilute, redox-active tracer allowed for the quantification of the mass-transport effects of bubble coverage during photoanodic O\u2082 (g) evolution at upward-facing photoanodes in 1.0 M KOH(aq.). Measurements of the gas coverage at upward-facing p-Si photocathodes in 0.50 M H\u2082SO\u2084 (aq.) allowed for the nucleation rate and contact angle of H\u2082 (g) bubbles to be evaluated for systems having various surface free energies. Under simulated solar illumination, the rapid departure of small O\u2082 (g) bubbles produced stable photocurrents at upward-facing oxygen-evolving Si photoanodes and yielded increased mass-transport velocities relative to a stagnant electrolyte, indicating that bubbles can provide a net benefit to the photoelectrochemical performance of an upward-facing photoanode in solar fuels devices.", "date": "2021-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "14", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "414-423", "id_number": "CaltechAUTHORS:20201124-121041867", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201124-121041867", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/d0ee02796k", "primary_object": { "basename": "d0ee02796k2.mp4", "url": "https://authors.library.caltech.edu/records/np129-58b77/files/d0ee02796k2.mp4" }, "related_objects": [ { "basename": "d0ee02796k3.mp4", "url": "https://authors.library.caltech.edu/records/np129-58b77/files/d0ee02796k3.mp4" }, { "basename": "d0ee02796k1.pdf", "url": "https://authors.library.caltech.edu/records/np129-58b77/files/d0ee02796k1.pdf" } ], "pub_year": "2021", "author_list": "Kempler, Paul A.; Ifkovits, Zachary P.; et el." }, { "id": "https://authors.library.caltech.edu/records/mvrm0-qa846", "eprint_id": 106370, "eprint_status": "archive", "datestamp": "2023-08-20 01:01:54", "lastmod": "2023-10-20 23:24:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Boyd-David-A", "name": { "family": "Boyd", "given": "David A." } }, { "id": "Soedarmadji-Edwin", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Bi Alloying into Rare Earth Double Perovskites Enhances Synthesizability and Visible Light Absorption", "ispublished": "pub", "full_text_status": "public", "keywords": "high throughput experimentation, alloy, ink jet printing, double perovskite, band gap engineering, bismuth, rare earth,\nlanthanide, elpasolite", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: August 28, 2020; Revised: October 12, 2020; Published: October 29, 2020. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The optical analysis to infer phase behavior was supported by the Air Force Office of Scientific Research under award number FA9550-18-1-0136. \n\nAuthor Contributions: The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript. P.F.N. Synthesized and collected optical data on the libraries and contributed to manuscript preparation. L.Z. collected and analyzed XRD data. M.U. analyzed Raman data. D.A.B. collected and analyzed Raman data. E.S. designed scripts for extracting individual sample images and arranging in composition space. J.A.H. facilitated aggregation of results and their interpretation in the context of the literature and contributed to manuscript preparation. J.M.G. designed the library printing strategy and supported the design of analysis algorithms and visualization schemes, supervised, and contributed to manuscript preparation. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - co0c00177_si_001.pdf
", "abstract": "A high throughput combinatorial synthesis utilizing inkjet printing of precursor inks was used to rapidly evaluate Bi-alloying into double perovskite oxides for enhanced visible light absorption. The fast visual screening of photo image scans of the library plates identifies 4-metal oxide compositions displaying an increase in light absorption, which subsequent UV\u2013vis spectroscopy indicates is due to bandgap reduction. Structural characterization by X-ray diffraction (XRD) and Raman spectroscopy demonstrates that the visually darker composition range contains Bi-alloyed Sm\u2082MnNiO\u2086 (double perovskite structure), of the form (Bi,Sm)\u2082MnNiO\u2086. Bi alloying not only increases the visible absorption but also facilitates crystallization of this structure at the relatively low annealing temperature of 615 \u00b0C. Investigation of additional seven combinations of a rare earth (RE) and a transition metal (TM) with Bi and Mn indicates that Bi-alloying on the RE site occurs with similar effect in the family of rare earth oxide double perovskites.", "date": "2020-12-14", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "22", "number": "12", "publisher": "American Chemical Society", "pagerange": "895-901", "id_number": "CaltechAUTHORS:20201030-154047149", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201030-154047149", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.0c00177", "primary_object": { "basename": "co0c00177_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mvrm0-qa846/files/co0c00177_si_001.pdf" }, "pub_year": "2020", "author_list": "Newhouse, Paul F.; Zhou, Lan; et el." }, { "id": "https://authors.library.caltech.edu/records/5sh4v-r4k88", "eprint_id": 106356, "eprint_status": "archive", "datestamp": "2023-08-20 01:01:44", "lastmod": "2023-10-20 23:23:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sutherland-Duncan-R", "name": { "family": "Sutherland", "given": "Duncan R." } }, { "id": "Connolly-Aine-B", "name": { "family": "Connolly", "given": "Aine Boyer" }, "orcid": "0000-0002-2721-5621" }, { "id": "Amsler-Maximilian", "name": { "family": "Amsler", "given": "Maximilian" }, "orcid": "0000-0001-8350-2476" }, { "id": "Chang-Ming-Chiang", "name": { "family": "Chang", "given": "Ming-Chiang" }, "orcid": "0000-0003-1880-6654" }, { "id": "Gann-Katie-Rose", "name": { "family": "Gann", "given": "Katie Rose" } }, { "id": "Gupta-Vidit", "name": { "family": "Gupta", "given": "Vidit" }, "orcid": "0000-0002-4869-5820" }, { "id": "Ament-Sebastian-E", "name": { "family": "Ament", "given": "Sebastian" } }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" }, { "id": "van-Dover-R-Bruce", "name": { "family": "van Dover", "given": "R. Bruce" }, "orcid": "0000-0002-6166-5650" }, { "id": "Thompson-Michael-O", "name": { "family": "Thompson", "given": "Michael O." } } ] }, "title": "Optical Identification of Materials Transformations in Oxide Thin Films", "ispublished": "pub", "full_text_status": "restricted", "keywords": "laser spike annealing, reflectance spectroscopy, high-throughput experimentation, materials transformations,\nmetastable phases", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: August 13, 2020; Revised: October 3, 2020; Published: October 29, 2020. \n\nThe authors acknowledge the Air Force Office of Scientific Research for support under award FA9550-18-1-0136. This work is based upon research conducted at the Materials Solutions Network at CHESS (MSN-C), which is supported by the Air Force Research Laboratory under award FA8650-19-2-5220. This work was also performed in part at the Cornell NanoScale Facility, a member of the National Nanotechnology Coordinated Infrastructure (NNCI), which is supported by the National Science Foundation (Grant NNCI-2025233). M.A. acknowledges support from the Swiss National Science Foundation (project P4P4P2-180669). \n\nAuthor Contributions: D.R.S. and A.B.C. contributed equally to this work. \n\nThe authors declare no competing financial interest.", "abstract": "Recent advances in high-throughput experimentation for combinatorial studies have accelerated the discovery and analysis of materials across a wide range of compositions and synthesis conditions. However, many of the more powerful characterization methods are limited by speed, cost, availability, and/or resolution. To make efficient use of these methods, there is value in developing approaches for identifying critical compositions and conditions to be used as a priori knowledge for follow-up characterization with high-precision techniques, such as micrometer-scale synchrotron-based X-ray diffraction (XRD). Here, we demonstrate the use of optical microscopy and reflectance spectroscopy to identify likely phase-change boundaries in thin film libraries. These methods are used to delineate possible metastable phase boundaries following lateral-gradient laser spike annealing (lg-LSA) of oxide materials. The set of boundaries are then compared with definitive determinations of structural transformations obtained using high-resolution XRD. We demonstrate that the optical methods detect more than 95% of the structural transformations in a composition-gradient La-Mn-O library and a Ga2O3 sample, both subject to an extensive set of lg-LSA anneals. Our results provide quantitative support for the value of optically detected transformations as a priori data to guide subsequent structural characterization, ultimately accelerating and enhancing the efficient implementation of micrometer-resolution XRD experiments.", "date": "2020-12-14", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "22", "number": "12", "publisher": "American Chemical Society", "pagerange": "887-894", "id_number": "CaltechAUTHORS:20201030-105644203", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201030-105644203", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA8650-19-2-5220" }, { "agency": "NSF", "grant_number": "NNCI-2025233" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P4P4P2-180669" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.0c00172", "pub_year": "2020", "author_list": "Sutherland, Duncan R.; Connolly, Aine Boyer; et el." }, { "id": "https://authors.library.caltech.edu/records/11rhx-p4g59", "eprint_id": 106405, "eprint_status": "archive", "datestamp": "2023-08-20 00:52:23", "lastmod": "2023-10-20 23:27:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Flores-Espinosa-Michelle-M", "name": { "family": "Flores Espinosa", "given": "Michelle M." }, "orcid": "0000-0002-5697-1290" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xu-Mingjie", "name": { "family": "Xu", "given": "Mingjie" } }, { "id": "Abatemarco-Luca", "name": { "family": "Abatemarco", "given": "Luca" } }, { "id": "Choi-Chungseok", "name": { "family": "Choi", "given": "Chungseok" }, "orcid": "0000-0001-9169-1393" }, { "id": "Pan-Xiaoqing", "name": { "family": "Pan", "given": "Xiaoqing" }, "orcid": "0000-0002-0965-8568" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Zhao-Zhipeng", "name": { "family": "Zhao", "given": "Zipeng" }, "orcid": "0000-0003-1135-6742" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" } ] }, "title": "Compressed Intermetallic PdCu for Enhanced Electrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: September 14, 2020; Accepted: October 26, 2020; Published: November 3, 2020. \n\nY.H., W.A.G., Z.Z., and M.F.E. acknowledge the support from Office of Naval Research (N000141812155). T.C. was supported by the Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and the 111 Project. W.A.G. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation Grant No. ACI-1548562. The work at UC Irvine was supported by the National Science Foundation with Grants CBET 1159240, DMR1420620, and DMR-1506535. TEM work on JEM Grand ARM was conducted using the facilities in the Irvine Materials Research Institute (IMRI) at the University of California Irvine. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c01959_si_001.pdf
", "abstract": "Hydrogen evolution reaction (HER) is a key reaction in hydrogen production through water electrolysis. Platinum (Pt) is the best-known element for HER catalysis. Due to the scarcity of Pt, the development of non-Pt nanocatalysts is desired to achieve broad scale implementations. Here we demonstrate that the PdCu nanostructure containing an intermetallic B2 phase (PdCu-B2) shows a smaller Tafel slope, higher exchange current density, and lower overpotential for HER compared to commercial Pt/C in acidic conditions. Density functional theory (DFT) calculations demonstrate that the improved HER performance in acidic conditions can be attributed to the decrease in the hydrogen binding energy (HBE) on the compressed intermetallic PdCu-B2, shifting the HBE to a more optimal position even compared to Pt/C. In addition, PdCu-B2 exhibits the highest mass activity toward the formic acid oxidation reaction, making it a good anode catalyst candidate for formic-acid-based fuel cells.", "date": "2020-12-11", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "12", "publisher": "American Chemical Society", "pagerange": "3672-3680", "id_number": "CaltechAUTHORS:20201103-135137512", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201103-135137512", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141812155" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Jiangsu Higher Education Institutions" }, { "agency": "111 Project of China" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "NSF", "grant_number": "CBET-1159240" }, { "agency": "NSF", "grant_number": "DMR-1420620" }, { "agency": "NSF", "grant_number": "DMR-1506535" } ] }, "other_numbering_system": { "items": [ { "id": "1396", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.0c01959", "primary_object": { "basename": "nz0c01959_si_001.pdf", "url": "https://authors.library.caltech.edu/records/11rhx-p4g59/files/nz0c01959_si_001.pdf" }, "pub_year": "2020", "author_list": "Flores Espinosa, Michelle M.; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/szhan-9tf52", "eprint_id": 100901, "eprint_status": "archive", "datestamp": "2023-08-22 07:53:59", "lastmod": "2023-10-19 22:13:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Korzeniewski-Carol-L", "name": { "family": "Korzeniewski", "given": "Carol L." }, "orcid": "0000-0003-3672-0731" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Tracking the prelude of the electroreduction of carbon monoxide via its interaction with Cu(100): Studies by operando scanning tunneling microscopy and infrared spectroscopy", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Seriatim STM-PMIRS; Operando electrode-surface microscopy; Operando molecular vibrational spectroscopy; Potential-dependent CO adsorption on Cu(100)", "note": "\u00a9 2020 Published by Elsevier B.V. \n\nReceived 11 March 2019, Revised 21 January 2020, Accepted 23 January 2020, Available online 24 January 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "The first isolable intermediate in the electrochemical reduction of carbon dioxide is carbon monoxide. This species, or its hydrated form, formic acid, is also the primary end product from all but a handful of metallic electrodes; with the latter, hydrogen gas is generated, but it emanates from the reduction of water and not from CO\u2082. Only one electrode material, zerovalent copper, can spawn, in greater-than-trace quantities, a variety of species that are more highly reduced than CO. Hence, if the aim is to pursue a reaction trail of the reduction of CO\u2082 to products other than CO, it would be both logical and expedient to track the electrocatalytic reaction of CO itself. Heterogeneous electrocatalysis is a surface phenomenon; it transpires only when the reactant, CO in this case, chemisorbs on, or chemically interacts with, the Cu electrode surface. There is no electrocatalytic reaction if there is no CO adsorption. In ultrahigh vacuum, no CO resides on the Cu(100) surface at temperatures higher than 200 K. However, under electrochemical conditions, CO is chemisorbed on Cu at ambient temperatures at a given potential. We thus paired, in seriatim fashion, scanning tunneling microscopy (STM) and polarization-modulation IR reflection-absorption spectroscopy (PMIRS) to document the influence of applied potential on the coverage, the molecular orientation, and the adlattice structure of CO adsorbed on Cu(100) in alkaline solutions; the results are described in this paper.", "date": "2020-12-01", "date_type": "published", "publication": "Catalysis Today", "volume": "358", "publisher": "Elsevier", "pagerange": "210-214", "id_number": "CaltechAUTHORS:20200124-132304036", "issn": "0920-5861", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200124-132304036", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.cattod.2020.01.028", "pub_year": "2020", "author_list": "Baricuatro, Jack H.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/dd01c-94550", "eprint_id": 105630, "eprint_status": "archive", "datestamp": "2023-08-20 00:33:40", "lastmod": "2023-10-20 22:11:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "New Quantum Mechanics Based Methods for Multiscale Simulations with Applications to Reaction Mechanisms for Electrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Springer. \n\nPublished: 28 September 2020. \n\nThe research on CO\u2082 reduction was supported as part of the Joint Center for Artificial Photosynthesis, an Energy Innovation Hub funded by the U.S. Department of Energy, Office of Science. (DE-SC0004993). The research on ORR is funded by ONR (N00014-18-1-2155). The research on OER is funded by NSF (CBET-1805022). There is no direct funding for RexPoN, but it is supported by these other projects. \n\nDedication: To Robert Grasselli, pioneer in improving catalysis and catalysts through atomistic reasoning and mechanism. Inspiration for the Irsee Catalysis meetings and for my entry into the wonderful complex world of Heterogeneous catalysis. \n\nWe declare no Conflicts of Interest.\n\nAccepted Version - 1397-Goddard-IRSEE-VIII-Electrochem-20-01-11-modified-20-08-28-final.pdf
", "abstract": "Electrocatalysis may provide the solution to some of the most important energy and environmental problems facing society: converting solar energy during the day to fuel (H\u2082) that can provide power at night (hydrogen fuel cells) through water splitting, \u00b7reducing the CO\u2082 in the atmosphere to valuable chemicals (methane, ethylene, ethanol). However significant improvements must be made in the selectivity and activity of current electrocatalysts to obtain practical solutions. A great many experiments are underway to find such solutions, but the progress is slow. We consider that quantum mechanics based multiscale simulations can dramatically accelerate the progress by identifying the reaction mechanisms involved and the using in silico methods to predict the best modifications to Improve performance. We will discuss some of the progress in developing the methods needed and applying them to improving electrocatalysts.", "date": "2020-12", "date_type": "published", "publication": "Topics in Catalysis", "volume": "63", "number": "19-20", "publisher": "Springer", "pagerange": "1658-1666", "id_number": "CaltechAUTHORS:20200929-101500549", "issn": "1022-5528", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200929-101500549", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-18-1-2155" }, { "agency": "NSF", "grant_number": "CBET-1805022" } ] }, "other_numbering_system": { "items": [ { "id": "1397", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s11244-020-01369-x", "primary_object": { "basename": "1397-Goddard-IRSEE-VIII-Electrochem-20-01-11-modified-20-08-28-final.pdf", "url": "https://authors.library.caltech.edu/records/dd01c-94550/files/1397-Goddard-IRSEE-VIII-Electrochem-20-01-11-modified-20-08-28-final.pdf" }, "pub_year": "2020", "author_list": "Goddard, William A., III" }, { "id": "https://authors.library.caltech.edu/records/c5dvp-1kw67", "eprint_id": 90823, "eprint_status": "archive", "datestamp": "2023-08-22 07:43:07", "lastmod": "2023-10-19 14:55:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Abdellah-Mohamed", "name": { "family": "Abdellah", "given": "Mohamed" } }, { "id": "Habib-Adela", "name": { "family": "Habib", "given": "Adela" } }, { "id": "Gosztola-David-J", "name": { "family": "Gosztola", "given": "David J." }, "orcid": "0000-0003-2674-1379" }, { "id": "Hattori-Yocefu", "name": { "family": "Hattori", "given": "Yocefu" } }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Zheng-Kaibo", "name": { "family": "Zheng", "given": "Kaibo" } }, { "id": "Canton-Sophie-E", "name": { "family": "Canton", "given": "Sophie E." }, "orcid": "0000-0003-4337-8129" }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "S\u00e1-Jacinto", "name": { "family": "S\u00e1", "given": "Jacinto" }, "orcid": "0000-0003-2124-9510" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Ultrafast hot-hole injection modifies hot-electron dynamics in Au/p-GaN heterostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "Nanophotonics and plasmonics; Optoelectronic devices and components", "note": "\u00a9 2020 The Author(s), under exclusive licence to Springer Nature Limited. \n\nReceived 06 December 2018; Accepted 16 June 2020; Published 27 July 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE-SC0004993. A portion of the ultrafast spectroscopy work was performed at the Center for Nanoscale Materials, a US Department of Energy Office of Science User Facility, and supported by the US Department of Energy, Office of Science, under contract no. DE-AC02-06CH11357. G.T. acknowledges support from the Swiss National Science Foundation through the Early Postdoc. Mobility Fellowship, grant no. P2EZP2_159101 and the Advanced Mobility Fellowship, grant no. P300P2_171417. We also thank M. V. Pavliuk for assistance in conducting ultrafast transient absorption spectroscopy measurements from planar Au films on p-GaN substrates. \n\nData availability: The datasets generated and analysed during the study are available from the corresponding authors upon request. \n\nAuthor Contributions: These authors contributed equally: Giulia Tagliabue, Joseph S. DuChene, Mohamed Abdellah. \n\nJ.S.D., G.T. and H.A.A. conceived the idea, designed the experiments, analysed data and wrote the manuscript with contributions from all authors. M.A., Y.H. and J.S. performed infrared transient absorption spectroscopy experiments. M.A., K.Z., S.E.C. and D.J.G. performed visible transient absorption spectroscopy experiments. A.H. and R.S. performed ab initio theory calculations. J.S.D. and G.T. fabricated and characterized materials. W.-H.C. acquired absorption spectra of materials. H.A.A. supervised the project. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing interests.\n\nSubmitted - 1810.04238.pdf
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Supplemental Material - 41563_2020_737_MOESM1_ESM.pdf
", "abstract": "A fundamental understanding of hot-carrier dynamics in photo-excited metal nanostructures is needed to unlock their potential for photodetection and photocatalysis. Despite numerous studies on the ultrafast dynamics of hot electrons, so far, the temporal evolution of hot holes in metal\u2013semiconductor heterostructures remains unknown. Here, we report ultrafast (t\u2009<\u2009200\u2009fs) hot-hole injection from Au nanoparticles into the valence band of p-type GaN. The removal of hot holes from below the Au Fermi level is observed to substantially alter the thermalization dynamics of hot electrons, reducing the peak electronic temperature and the electron\u2013phonon coupling time of the Au nanoparticles. First-principles calculations reveal that hot-hole injection modifies the relaxation dynamics of hot electrons in Au nanoparticles by modulating the electronic structure of the metal on timescales commensurate with electron\u2013electron scattering. These results advance our understanding of hot-hole dynamics in metal\u2013semiconductor heterostructures and offer additional strategies for manipulating the dynamics of hot carriers on ultrafast timescales.", "date": "2020-12", "date_type": "published", "publication": "Nature Materials", "volume": "19", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "1312-1318", "id_number": "CaltechAUTHORS:20181112-073640797", "issn": "1476-1122", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181112-073640797", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41563-020-0737-1", "primary_object": { "basename": "41563_2020_737_Fig7_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig7_ESM.webp" }, "related_objects": [ { "basename": "41563_2020_737_Fig8_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig8_ESM.webp" }, { "basename": "41563_2020_737_Fig9_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig9_ESM.webp" }, { "basename": "41563_2020_737_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_MOESM1_ESM.pdf" }, { "basename": "1810.04238.pdf", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/1810.04238.pdf" }, { "basename": "41563_2020_737_Fig10_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig10_ESM.webp" }, { "basename": "41563_2020_737_Fig11_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig11_ESM.webp" }, { "basename": "41563_2020_737_Fig6_ESM.webp", "url": "https://authors.library.caltech.edu/records/c5dvp-1kw67/files/41563_2020_737_Fig6_ESM.webp" } ], "pub_year": "2020", "author_list": "Tagliabue, Giulia; DuChene, Joseph S.; et el." }, { "id": "https://authors.library.caltech.edu/records/9t53z-44f43", "eprint_id": 104604, "eprint_status": "archive", "datestamp": "2023-08-20 00:27:31", "lastmod": "2023-10-20 22:59:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ribson-Ryan-D", "name": { "family": "Ribson", "given": "Ryan D." } }, { "id": "Choi-Gyeongshin", "name": { "family": "Choi", "given": "Gyeongshin" } }, { "id": "Hadt-R-G", "name": { "family": "Hadt", "given": "Ryan G." }, "orcid": "0000-0001-6026-1358" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Controlling Singlet Fission with Coordination Chemistry-Induced Assembly of Dipyridyl Pyrrole Bipentacenes", "ispublished": "pub", "full_text_status": "public", "keywords": "Nuclear fission, Hydrocarbons, Absorption, Fluorescence, Aromatic compounds", "note": "\u00a9 2020 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: August 5, 2020; Published: November 10, 2020. \n\nThe authors thank Dr. Jay Winkler for assistance with time-resolved luminescence measurements, the Beckman Institute Laser Resource Center (BILRC) for access to the associated equipment, and Dr. David VanderVelde for NMR support and helpful discussions. Mike Takase and Larry Henling are acknowledged for crystallographic assistance. T.A. is grateful for the support provided by King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia, offered under the KFUPM-Caltech Research Collaboration and the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. Financial support from Caltech and the Dow Next Generation Educator Fund is gratefully acknowledged (R.G.H.). \n\nThe authors declare no competing financial interest.\n\nPublished - acscentsci.0c01044.pdf
Supplemental Material - oc0c01044_si_001.pdf
", "abstract": "Singlet fission has the potential to surpass current efficiency limits in next-generation photovoltaics and to find use in quantum information science. Despite the demonstration of singlet fission in various materials, there is still a great need for fundamental design principles that allow for tuning of photophysical parameters, including the rate of fission and triplet lifetimes. Here, we describe the synthesis and photophysical characterization of a novel bipentacene dipyridyl pyrrole (HDPP-Pent) and its Li- and K-coordinated derivatives. HDPP-Pent undergoes singlet fission at roughly 50% efficiency (\u03c4_(SF) = 730 ps), whereas coordination in the Li complex induces significant structural changes to generate a dimer, resulting in a 7-fold rate increase (\u03c4_(SF) = 100 ps) and more efficient singlet fission with virtually no sacrifice in triplet lifetime. We thus illustrate novel design principles to produce favorable singlet fission properties, wherein through-space control can be achieved via coordination chemistry-induced multipentacene assembly.", "date": "2020-11-25", "date_type": "published", "publication": "ACS Central Science", "volume": "6", "number": "11", "publisher": "American Chemical Society", "pagerange": "2088-2096", "id_number": "CaltechAUTHORS:20200728-104820571", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200728-104820571", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "King Fahd University of Petroleum and Minerals (KFUPM)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech" }, { "agency": "Dow Next Generation Educator Fund" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscentsci.0c01044", "pmcid": "PMC7706079", "primary_object": { "basename": "Controlling_Singlet_Fission_with_Coordination_Chemistry-Induced_Assembly_of_Dipyridyl_Pyrrole_Bipentacenes_v1.pdf", "url": "https://authors.library.caltech.edu/records/9t53z-44f43/files/Controlling_Singlet_Fission_with_Coordination_Chemistry-Induced_Assembly_of_Dipyridyl_Pyrrole_Bipentacenes_v1.pdf" }, "related_objects": [ { "basename": "acscentsci.0c01044.pdf", "url": "https://authors.library.caltech.edu/records/9t53z-44f43/files/acscentsci.0c01044.pdf" }, { "basename": "oc0c01044_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9t53z-44f43/files/oc0c01044_si_001.pdf" } ], "pub_year": "2020", "author_list": "Ribson, Ryan D.; Choi, Gyeongshin; et el." }, { "id": "https://authors.library.caltech.edu/records/eb8q2-9fd59", "eprint_id": 106589, "eprint_status": "archive", "datestamp": "2023-08-20 00:28:24", "lastmod": "2023-10-20 22:59:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bui-Justin-C", "name": { "family": "Bui", "given": "Justin C." }, "orcid": "0000-0003-4525-957X" }, { "id": "Digdaya-Ibadillah-A", "name": { "family": "Digdaya", "given": "Ibadillah" }, "orcid": "0000-0001-7349-0934" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Bell-Alexis-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" }, { "id": "Weber-Adam-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" } ] }, "title": "Understanding Multi-Ion Transport Mechanisms in Bipolar Membranes", "ispublished": "pub", "full_text_status": "public", "keywords": "bipolar membrane, transport, model, electrochemistry, ionomers, electrolysis, CO2 reduction, water splitting", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: July 14, 2020; Accepted: October 23, 2020; Published: November 10, 2020. \n\nThis material is based on work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993 and the National Institutes of Health under grant no. S10OD023532. J.C.B. acknowledges funding from the National Science Foundation Graduate Research Fellowship under grant no. DGE 1752814. The authors would also like to thank David Vermaas, Philomena Weng, and Andrew Crothers for insightful and fruitful discussions regarding the nature of ionic transport in bipolar membranes. \n\nThe authors declare no competing financial interest.\n\nCorrection to \"Understanding Multi-Ion Transport Mechanisms in Bipolar Membranes\"\nJustin C. Bui, Ibadillah Digdaya, Chengxiang Xiang, Alexis T. Bell, and Adam Z. Weber.\nACS Applied Materials & Interfaces Article ASAP;\nDOI: 10.1021/acsami.1c07630\n\nSupplemental Material - am0c12686_si_001.pdf
", "abstract": "Bipolar membranes (BPMs) have the potential to become critical components in electrochemical devices for a variety of electrolysis and electrosynthesis applications. Because they can operate under large pH gradients, BPMs enable favorable environments for electrocatalysis at the individual electrodes. Critical to the implementation of BPMs in these devices is understanding the kinetics of water dissociation that occurs within the BPM as well as the co- and counter-ion crossover through the BPM, which both present significant obstacles to developing efficient and stable BPM-electrolyzers. In this study, a continuum model of multi-ion transport in a BPM is developed and fit to experimental data. Specifically, concentration profiles are determined for all ionic species, and the importance of a water-dissociation catalyst is demonstrated. The model describes internal concentration polarization and co- and counter-ion crossover in BPMs, determining the mode of transport for ions within the BPM and revealing the significance of salt-ion crossover when operated with pH gradients relevant to electrolysis and electrosynthesis. Finally, a sensitivity analysis reveals that the performance and lifetime of BPMs can be improved substantially by using of thinner dissociation catalysts, managing water transport, modulating the thickness of the individual layers in the BPM to control salt-ion crossover, and increasing the ion-exchange capacity of the ion-exchange layers in order to amplify the water-dissociation kinetics at the interface.", "date": "2020-11-25", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "12", "number": "47", "publisher": "American Chemical Society", "pagerange": "52509-52526", "id_number": "CaltechAUTHORS:20201110-121459166", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201110-121459166", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NIH", "grant_number": "S10OD023532" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1752814" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.0c12686", "primary_object": { "basename": "am0c12686_si_001.pdf", "url": "https://authors.library.caltech.edu/records/eb8q2-9fd59/files/am0c12686_si_001.pdf" }, "pub_year": "2020", "author_list": "Bui, Justin C.; Digdaya, Ibadillah; et el." }, { "id": "https://authors.library.caltech.edu/records/d9826-7xc92", "eprint_id": 104651, "eprint_status": "archive", "datestamp": "2023-08-20 00:20:18", "lastmod": "2023-10-20 20:41:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" }, "orcid": "0000-0002-2955-9671" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Modeling the Performance of A Flow-Through Gas Diffusion Electrode for Electrochemical Reduction of CO or CO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Electrochemical Society (\"ECS\"). Published on behalf of ECS by IOP Publishing Limited. \n\nReceived 15 January 2020; Accepted Manuscript online 1 June 2020; Published 1 July 2020. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nPublished - Chen_2020_J._Electrochem._Soc._167_114503.pdf
Supplemental Material - JES_167_11_114503_suppdata.pdf
", "abstract": "A flow-through gas diffusion electrode (GDE) consisting of agglomerate catalysts for CO or CO\u2082 reduction, gas channels for reactants, aqueous electrolytes for ionic transport, and metallic current collectors was simulated and evaluated using a numerical model. The geometric partial current densities and Faradaic Efficiencies (FE) for CH\u2084, C\u2082H\u2084 and H\u2082 generation in GDEs were calculated and compared to the behavior of analogous aqueous-based planar electrodes. The pH-dependent kinetics for CH\u2084 and C\u2082H\u2084 generation were used to represent the intrinsic catalytic characteristics for the agglomerate catalyst. The modeling indicated that relative to planar electrodes for either CO reduction (COR) or CO\u2082 reduction (CO\u2082R), substantial increases in electrochemical reduction rates and Faradaic efficiencies are expected when flow-through GDEs are used. The spatially resolved pH and reaction rates within the flow-through GDEs were also simulated for two different operating pHs, and the resulting transport losses were analyzed quantitatively. For CO\u2082 reduction, substantial loss of CO\u2082 via chemical reaction with the locally alkaline electrolyte was observed due to the increased pH in operating GDEs.", "date": "2020-11-11", "date_type": "published", "publication": "Journal of The Electrochemical Society", "volume": "167", "number": "11", "publisher": "The Electrochemical Society", "pagerange": "Art. No. 114503", "id_number": "CaltechAUTHORS:20200730-073238681", "issn": "1945-7111", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200730-073238681", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/1945-7111/ab987a", "primary_object": { "basename": "Chen_2020_J._Electrochem._Soc._167_114503.pdf", "url": "https://authors.library.caltech.edu/records/d9826-7xc92/files/Chen_2020_J._Electrochem._Soc._167_114503.pdf" }, "related_objects": [ { "basename": "JES_167_11_114503_suppdata.pdf", "url": "https://authors.library.caltech.edu/records/d9826-7xc92/files/JES_167_11_114503_suppdata.pdf" } ], "pub_year": "2020", "author_list": "Chen, Yikai; Lewis, Nathan S.; et el." }, { "id": "https://authors.library.caltech.edu/records/z2w0e-q5s88", "eprint_id": 105755, "eprint_status": "archive", "datestamp": "2023-08-20 00:15:39", "lastmod": "2023-10-20 22:23:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Boyd-D-A", "name": { "family": "Boyd", "given": "David A." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" } ] }, "title": "Enhanced Bulk Transport in Copper Vanadate Photoanodes Identified by Combinatorial Alloying", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Elsevier Inc. \n\nReceived 3 July 2020, Revised 8 August 2020, Accepted 27 August 2020, Available online 1 October 2020. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy (award no. DE-SC0004993). \n\nAuthor Contributions: P.F.N. synthesized and collected optical and PEC data on the libraries and contributed to manuscript preparation. D.G. performed data analysis and visualization of the library data. L.Z. collected and analyzed XRD data. Y.W. collected library PEC data. M.U. analyzed Raman data. D.A.B. collected and analyzed Raman data. J.M.G. designed the library printing strategy and supported the design of analysis algorithms and visualization schemes. J.A.H. facilitated aggregation of results and their interpretation in the context of the literature. J.M.G. and J.A.H. supervised and contributed to manuscript preparation. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 1-s2.0-S2590238520304963-mmc1.pdf
", "abstract": "The impact of alloying on the performance of \u03b2-Cu\u2082V\u2082O\u2087 photoanodes was investigated using inkjet printing of composition libraries containing 1,809 Cu\u2082V\u2082O\u2087-based photoanodes. Six elements (Zr, Ca, Hf, Gd, La, and Lu) were alloyed and pairwise co-alloyed at concentrations up to 7 at % into Cu-rich, stoichiometric, and Cu-deficient host Cu\u2082V\u2082O\u2087. A 1.7-fold increase in oxygen evolution photocurrent in pH 9.2 electrolyte was obtained by alloying Ca into \u03b2-Cu\u2082V\u2082O\u2087. Experiments employing a hole scavenger to better characterize bulk charge separation and transport revealed a 2.2-fold increase in photoactivity via alloying with Hf, Zr, and La, which increased to 2.7-fold upon co-alloying these elements with Ca. Concurrent with increased photoactivity is substantially decreased photon absorption between 1.5 and 2 eV, a range reported to coincide with high exciton absorption in \u03b2-Cu\u2082V\u2082O\u2087, motivating further exploration of whether these co-alloy compositions may destabilize the excitonic state that appears to have limited performance to date.", "date": "2020-11-04", "date_type": "published", "publication": "Matter", "volume": "3", "number": "5", "publisher": "Cell Press", "pagerange": "1601-1613", "id_number": "CaltechAUTHORS:20201002-103843089", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-103843089", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2020.08.032", "primary_object": { "basename": "1-s2.0-S2590238520304963-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/z2w0e-q5s88/files/1-s2.0-S2590238520304963-mmc1.pdf" }, "pub_year": "2020", "author_list": "Newhouse, Paul F.; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/xjvca-5fq59", "eprint_id": 105772, "eprint_status": "archive", "datestamp": "2023-08-22 07:12:16", "lastmod": "2023-10-20 22:24:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Quaternary Oxide Photoanode Discovery Improves the Spectral Response and Photovoltage of Copper Vanadates", "ispublished": "pub", "full_text_status": "restricted", "keywords": "solar fuels; oxygen evolution reaction (OER); photoanode; copper vanadates; quaternary metal oxides; photoelectrochemistry; high-throughput experimentation", "note": "\u00a9 2020 Elsevier. \n\nReceived 3 July 2020, Revised 8 August 2020, Accepted 27 August 2020, Available online 1 October 2020. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (award DE-SC0004993). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under contract DEAC02-76SF00515. The authors thank Douglas van Campen and Apurva Mehta for assistance with synchrotron XRD measurements. \n\nAuthor Contributions. L.Z. synthesized the composition libraries, collected and analyzed the composition (XRF) and crystal structure (XRD) data, and performed data analysis and visualization. A.S., Y.W., Y.L., and K.K. collected and A.S., L.Z., and D.G. analyzed the PEC data. D.G. also developed data analysis and visualization algorithms. P.F.N. collected and analyzed the optical data. S.K.S., L.Z., and J.M.G. designed the composition spaces for exploration and performed synchrotron XRD measurements. J.M.G. also supervised the project and participated in data analysis and interpretation. L.Z. and J.M.G. wrote the manuscript with contributions from J.A.H. and input from each author. \n\nThe authors declare no competing interests.", "abstract": "Copper vanadates are a promising class of solar fuel photoanodes with broad spectral response and excellent operational stability. The present performance limitations of these photoanodes are most evident in the rapid decrease in photoactivity with decrease in either photon energy or applied bias, the former limiting efficient utilization of the solar spectrum and the latter limiting photovoltage. We designed high-throughput photoelectrochemical screening to characterize these two aspects of improving Cu-V-based photoanodes in quaternary oxide composition spaces of the form Cu-V-X-O, where X = Mg, Ca, Sr, Fe. The results reveal that alloying of 2+ cations onto the Cu site of copper vanadates can improve photoelectrochemical properties, and Sr-alloyed Cu\u2085V\u2082O\u2081\u2080 emerges as the most promising photoanode providing the best combination of photovoltage and spectral response. Six quaternary oxide phases are discovered as photoanodes with visible light activity below 1.23 V versus reversible hydrogen electrode, highlighting the high-throughput photoanode discovery.", "date": "2020-11-04", "date_type": "published", "publication": "Matter", "volume": "3", "number": "5", "publisher": "Cell Press", "pagerange": "1614-1630", "id_number": "CaltechAUTHORS:20201002-151459149", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201002-151459149", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2020.08.031", "pub_year": "2020", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/na9zw-j5x42", "eprint_id": 105852, "eprint_status": "archive", "datestamp": "2023-08-20 00:12:17", "lastmod": "2023-10-20 22:29:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." } }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" }, "orcid": "0000-0002-2955-9671" }, { "id": "Nunez-Paul-D", "name": { "family": "Nunez", "given": "Paul D." }, "orcid": "0000-0001-7039-0516" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Failure modes of protection layers produced by atomic layer deposition of amorphous TiO\u2082 on GaAs anodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 26 Jun 2020; Accepted 23 Sep 2020; First published 23 Sep 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We gratefully acknowledge a gift from the Lam Research Unlock Ideas program. Deposition of a-TiO\u2082 in a cleanroom was performed in the Kavli Nanoscience Institute (KNI) at Caltech, and we thank the KNI staff for their assistance during fabrication. \n\nThere are no conflicts of interest to declare.\n\nSupplemental Material - d0ee02032j1.pdf
", "abstract": "Amorphous titanium dioxide (a-TiO\u2082) films formed by atomic layer deposition can serve as protective coatings for semiconducting photoanodes in water-splitting cells using strongly alkaline aqueous electrolytes. Herein, we experimentally examine the mechanisms of failure for p\u207a-GaAs anodes coated with a-TiO\u2082 films (GaAs/a-TiO\u2082). Galvanic displacement of exposed GaAs by Au allowed imaging of pinholes in the a-TiO\u2082 coatings, and enabled collection of quantitative and statistical data associated with pinhole defects. A combination of imaging, electrochemical measurements, and quantitative analyses of corrosion products indicated that extrinsic pinholes were present in the a-TiO\u2082 films before electrochemical operation. During electrochemical operation these pinholes led to pitting corrosion of the underlying GaAs substrate. The dominant source of pinholes was the presence of atmospheric particulate matter on the GaAs surface during deposition of the a-TiO\u2082 layer. The pinhole density decreased substantially when the thickness of the a-TiO\u2082 coating increased beyond 45 nm, and approached zero when the thickness of the film exceeded 112 nm. The density of pinholes in films thinner than 45 nm decreased when the a-TiO\u2082 coating was deposited in an environmentally controlled cleanroom. Pinhole-free GaAs/a-TiO\u2082 devices were also tested via chronoamperometry to quantify the rate of pinhole formation during electrochemistry. The time-to-failure increased with thickness, suggesting that the failure mechanism may involve diffusion or migration through the film. However, other mechanisms may also contribute to the degradation of thicker films (>112 nm). Nevertheless, as previously hypothesized, extrinsic pinhole defects formed during deposition and testing control the short-term protective performance of the a-TiO\u2082 film for GaAs anodes evolving O\u2082 from water.", "date": "2020-11-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "13", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "4269-4279", "id_number": "CaltechAUTHORS:20201007-073929719", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201007-073929719", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/d0ee02032j", "primary_object": { "basename": "d0ee02032j1.pdf", "url": "https://authors.library.caltech.edu/records/na9zw-j5x42/files/d0ee02032j1.pdf" }, "pub_year": "2020", "author_list": "Buabthong, Pakpoom; Ifkovits, Zachary P.; et el." }, { "id": "https://authors.library.caltech.edu/records/cwck3-r7h84", "eprint_id": 106114, "eprint_status": "archive", "datestamp": "2023-08-20 00:12:26", "lastmod": "2023-10-20 23:06:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Enhanced stability of silicon for photoelectrochemical water oxidation through self-healing enabled by an alkaline protective electrolyte", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2020. \n\nSubmitted 16 Jul 2020; Accepted 06 Oct 2020; First published 06 Oct 2020. \n \nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. Research was in part carried out at the Molecular Materials Resource Center of the Beckman Institute. We thank M. H. Richter for assistance in automating day/night cycles. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d0ee02250k1.pdf
", "abstract": "Alkaline electrolytes impede the corrosion of Si photoanodes under positive potentials and/or illumination, due to the formation of a SiO_x layer that etches 2\u20133 orders of magnitude more slowly than Si. Hence during water oxidation under illumination, pinholes in protection layers on Si photoanodes result in the local formation of a protective, stabilizing passive oxide on the Si surface. However, operation under natural diurnal insolation cycles additionally requires protection strategies that minimize the dark corrosive etching rate of Si at pinholes. We show herein that addition of [Fe(CN)\u2086]\u00b3\u207b to 1.0 M KOH(aq) results in a self-healing process that extends the lifetime to >280 h of an np\u207a-Si(100) photoanode patterned with an array of Ni catalyst islands operated under simulated day/night cycles. The self-healing [Fe(CN)\u2086]\u00b3\u207b additive caused the exposed Si(100) surface to etch >180 times slower than the Si etch rate in 1.0 M KOH(aq) alone. No appreciable difference in etch rate or facet preference was observed between Si(100) and Si(111) surfaces in 1.0 M KOH(aq) with [Fe(CN)\u2086]\u00b3\u207b, indicating that the surface conformally oxidized before Si dissolved. The presence of [Fe(CN)\u2086]\u00b3\u207b minimally impacted the faradaic efficiency or overpotential of p\u207a-Si/Ni electrodes for the oxygen-evolution reaction.", "date": "2020-11-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "13", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "4132-4141", "id_number": "CaltechAUTHORS:20201016-131847563", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201016-131847563", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d0ee02250k", "primary_object": { "basename": "d0ee02250k1.pdf", "url": "https://authors.library.caltech.edu/records/cwck3-r7h84/files/d0ee02250k1.pdf" }, "pub_year": "2020", "author_list": "Fu, Harold J.; Moreno-Hernandez, Ivan A.; et el." }, { "id": "https://authors.library.caltech.edu/records/j02ha-dmz20", "eprint_id": 105375, "eprint_status": "archive", "datestamp": "2023-08-19 23:57:29", "lastmod": "2023-10-20 21:55:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Yi-Rung", "name": { "family": "Lin", "given": "Yi-Rung" }, "orcid": "0000-0003-0331-3822" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Peterson-Elizabeth-A", "name": { "family": "Peterson", "given": "Elizabeth A." }, "orcid": "0000-0001-5379-3604" }, { "id": "Went-Cora-M", "name": { "family": "Went", "given": "Cora M." }, "orcid": "0000-0001-7737-3348" }, { "id": "Al-Balushi-Zakaria-Y", "name": { "family": "Al Balushi", "given": "Zakaria Y." }, "orcid": "0000-0003-0589-1618" }, { "id": "Jariwala-Deep", "name": { "family": "Jariwala", "given": "Deep" }, "orcid": "0000-0002-3570-8768" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Chen-Li-Chyong", "name": { "family": "Chen", "given": "Li-Chyong" }, "orcid": "0000-0001-6373-7729" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Band Edge Tailoring in Few-Layer Two-Dimensional Molybdenum Sulfide/Selenide Alloys", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 17, 2020; Revised: September 11, 2020; Published: September 14, 2020. \n\nThis work was performed in the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993. X-ray photoelectron spectroscopy was carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. Y.-R.L. acknowledges supports from the Ministry of Science and Technology (MoST), Taiwan. Y.-R.L. also acknowledges financial support by the Center of Atomic Initiative for New Materials, National Taiwan University, from the Featured Areas Research Center Program within the framework of the Higher Education Sprout Project by the Ministry of Education in Taiwan (108L9008). \n\nThe authors declare no competing financial interest.\n\nAccepted Version - acs.jpcc.0c04719
Supplemental Material - jp0c04719_si_001.pdf
", "abstract": "Chemical alloying is a powerful approach to tune the electronic structure of semiconductors and has led to the synthesis of ternary and quaternary two-dimensional (2D) dichalcogenide semiconductor alloys (e.g., MoSSe\u2082, WSSe\u2082, etc.). To date, most of the studies have been focused on determining the chemical composition by evaluating the optical properties, primarily via photoluminescence and reflection spectroscopy of these materials in the 2D monolayer limit. However, a comprehensive study of alloying in multilayer films with direct measurement of electronic structure, combined with first-principles theory, is required for a complete understanding of this promising class of semiconductors. We have combined first-principles density functional theory calculations with experimental characterization of MoS_(2(1-x))Se_(2x) (where x ranges from 0 to 1) alloys using X-ray photoelectron spectroscopy to evaluate the valence and conduction band edge positions in each alloy. Moreover, our observations reveal that the valence band edge energies for molybdenum sulfide/selenide alloys increase as a function of increasing selenium concentration. These experimental results agree well with the results of density functional theory calculations showing a similar trend in calculated valence band edges. Our studies suggest that alloying is an effective technique for tuning the band edges of transition-metal dichalcogenides, with implications for applications such as solar cells and photoelectrochemical devices.", "date": "2020-10-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "124", "number": "42", "publisher": "American Chemical Society", "pagerange": "22893-22902", "id_number": "CaltechAUTHORS:20200914-111809687", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200914-111809687", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Ministry of Science and Technology (Taipei)" }, { "agency": "National Taiwan University" }, { "agency": "Ministry of Education (Taipei)", "grant_number": "108L9008" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.0c04719", "primary_object": { "basename": "acs.jpcc.0c04719", "url": "https://authors.library.caltech.edu/records/j02ha-dmz20/files/acs.jpcc.0c04719" }, "related_objects": [ { "basename": "jp0c04719_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j02ha-dmz20/files/jp0c04719_si_001.pdf" } ], "pub_year": "2020", "author_list": "Lin, Yi-Rung; Cheng, Wen-Hui; et el." }, { "id": "https://authors.library.caltech.edu/records/10ge0-5h540", "eprint_id": 106046, "eprint_status": "archive", "datestamp": "2023-08-22 06:58:30", "lastmod": "2023-10-20 23:02:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "Chu F." } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald C." }, "orcid": "0000-0002-0306-5462" }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." }, "orcid": "0000-0003-2467-6630" } ] }, "title": "Reprint of \"Selective conversion of CO into ethanol on Cu(511) surface reconstructed from Cu(pc): Operando studies by electrochemical scanning tunneling microscopy, mass spectrometry, quartz crystal nanobalance, and infrared spectroscopy\"", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electrochemically generated Cu(511) surface; Operando electrode-surface microscopy; Operando molecular vibrational spectroscopy; CO adsorption on Cu vicinal surface; Selective reduction of CO into ethanol", "note": "\u00a9 2019 Elsevier B.V. \n\nReceived 30 September 2019, Revised 20 November 2019, Accepted 26 November 2019, Available online 13 October 2020. \n\nA publisher's error resulted in this article appearing in the wrong issue. The article is reprinted here for the reader's convenience and for the continuity of the special issue. For citation purposes, please use the original publication details; Volume 857, 15 January 2020, 113704, DOI of original item: 10.1016/j.jelechem.2019.113704. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nAuthors contributions: J.H.B., Y.-G.K., C.F.T., A.C.J., K.D.C. and J.C.H. designed research. J.H.B., Y.-G.K., C.F.T., A.C.J., performed research. J.H.B., Y.-G.K., C.F.T., A.C.J., K.D.C. and J.C.H. analyzed data. J.H.B. wrote the paper. \n\nDeclaration of interest: None.", "abstract": "A polycrystalline copper, surface-terminated by a well-defined (511)-oriented facet, was electrochemically generated by a series of step-wise surface reconstruction and iterations of mild oxidative-reductive processes in 0.1 M KOH. The electrochemical reduction of CO on the resultant stepped surface was investigated by four surface-sensitive operando methodologies: electrochemical scanning tunneling microscopy (STM), electrochemical quartz crystal nanobalance (EQCN), differential electrochemical mass spectrometry (DEMS), and polarization-modulation infrared spectroscopy (PMIRS). The stepped surface catalyzed the facile conversion of CO into ethanol, the exclusive alcohol product at a low overpotential of \u22121.06 V (SHE) or \u2212 0.3 V (RHE). The chemisorption of CO was found to be a necessary prelude to ethanol production; i.e. the surface coverages, rather than solution concentrations, of CO and its surface-bound intermediates primarily dictate the reaction rates (current densities). Contrary to the expected predominance of undercoordinated step-site reactivity over the coordination chemistry of vicinal surfaces, vibrational spectroscopic evidence reveals the involvement of terrace-bound CO adsorbates during the multi-atomic transformations associated with the production of ethanol.", "date": "2020-10-15", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "875", "publisher": "Elsevier", "pagerange": "Art. No. 114757", "id_number": "CaltechAUTHORS:20201013-154709745", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20201013-154709745", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2020.114757", "pub_year": "2020", "author_list": "Baricuatro, Jack H.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/0cyx0-8rq40", "eprint_id": 104974, "eprint_status": "archive", "datestamp": "2023-08-19 23:43:48", "lastmod": "2023-10-20 21:01:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Buabthong-Pakpoom", "name": { "family": "Buabthong", "given": "Pakpoom" }, "orcid": "0000-0001-5538-138X" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Dalleska-N-F", "name": { "family": "Dalleska", "given": "Nathan F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-4453-9716" }, { "id": "Brinkert-Katharina", "name": { "family": "Brinkert", "given": "Katharina" }, "orcid": "0000-0002-3593-5047" } ] }, "title": "Cathodic NH\u2084\u207a leaching of nitrogen impurities in CoMo thin-film electrodes in aqueous acidic solutions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 01 May 2020; Accepted 05 Aug 2020; First published 05 Aug 2020. \n\nK. B. acknowledges funding from the fellowship program of the German National Academy of Sciences \u2013 Leopoldina, grant LPDS 2016-06. Acknowledgment is made to the donors of The American Chemical Society Petroleum Research Fund for partial support of this research. Sample preparation and analyses were performed at the Joint Center for Artificial Photosynthesis, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, which also provided support for N. S. L., W. Y., P. B. and C. G. R. We acknowledge use of instrumentation in the Molecular Materials Research Center of the Beckman Institute at Caltech. N. F. D. is grateful to the Linde Center for support. The Environmental Analysis Center is supported by the Beckman Institute at Caltech. W. Y. and C. G. R. acknowledge the Resnick Sustainability Institute at Caltech for fellowship support. Dr Fabai Wu and Prof. Victoria Orphan are acknowledged for providing the \u00b9\u2075NH\u2084Cl standard reagent for UPLC-MS analysis. Mr Christopher Kenseth is thanked for assistance with UPLC-MS analysis. Dr Yuanlong Huang is acknowledged for assistance with chemiluminescence analysis. All authors would like to acknowledge the reviewers for their valuable comments in the first round. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d0se00674b1.pdf
", "abstract": "Electrocatalytic reduction of dinitrogen (N\u2082) to ammonium (NH\u2084\u207a) in acidic aqueous solutions was investigated at ambient temperature and pressure using a cobalt\u2013molybdenum (CoMo) thin-film electrode prepared by magnetron reactive sputtering. Increased concentrations of ammonium ions (NH\u2084\u207a) were consistently detected in the electrolyte using ion chromatography (IC) after constant-potential electrolysis at various potentials (\u2264\u22120.29 V vs. RHE). Using a newly developed analytical method based on ammonia derivatization, performing the experiments with \u00b9\u2075N\u2082-labelled gas led however to the detection of increased \u00b9\u2074NH\u2084\u207a concentrations instead of \u00b9\u2075NH\u2084\u207a. X-ray photoelectron spectroscopic (XPS) analysis of the electrode surface revealed the presence of Mo N and Mo\u2013NH_x species. Several contamination sources were identified that led to substantial increases in the concentration of ammonium ions, including \u00b9\u2075NH\u2083 impurities in \u00b9\u2075N\u2082 gas. The observed ammonium concentrations can be consistently ascribed to leaching of nitrogen (\u00b9\u2074N) impurities incorporated in the CoMo film during the sputtering process. Researchers in the field are therefore urged to adopt extended protocols to identify and eliminate sources of ammonia contamination and to very carefully monitor the ammonium concentrations in each experimental step.", "date": "2020-10-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "4", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "5080-5087", "id_number": "CaltechAUTHORS:20200817-095314564", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200817-095314564", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2016-06" }, { "agency": "American Chemical Society Petroleum Research Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/d0se00674b", "primary_object": { "basename": "d0se00674b1.pdf", "url": "https://authors.library.caltech.edu/records/0cyx0-8rq40/files/d0se00674b1.pdf" }, "pub_year": "2020", "author_list": "Yu, Weilai; Buabthong, Pakpoom; et el." }, { "id": "https://authors.library.caltech.edu/records/8snf1-1v863", "eprint_id": 104529, "eprint_status": "archive", "datestamp": "2023-09-22 22:41:13", "lastmod": "2023-10-23 23:27:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Chungseok", "name": { "family": "Choi", "given": "Chungseok" }, "orcid": "0000-0001-9169-1393" }, { "id": "Kwon-Soonho", "name": { "family": "Kwon", "given": "Soonho" }, "orcid": "0000-0002-9225-3018" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xu-Mingjie", "name": { "family": "Xu", "given": "Mingjie" } }, { "id": "Tieu-Peter", "name": { "family": "Tieu", "given": "Peter" }, "orcid": "0000-0001-8727-2313" }, { "id": "Lee-Changsoo", "name": { "family": "Lee", "given": "Changsoo" } }, { "id": "Cai-Jin", "name": { "family": "Cai", "given": "Jin" } }, { "id": "Lee-Hyuck-Mo", "name": { "family": "Lee", "given": "Hyuck Mo" }, "orcid": "0000-0003-4556-6692" }, { "id": "Pan-Xiaoqing", "name": { "family": "Pan", "given": "Xiaoqing" }, "orcid": "0000-0002-0965-8568" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" } ] }, "title": "Highly active and stable stepped Cu surface for enhanced electrochemical CO\u2082 reduction to C\u2082H\u2084", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrocatalysis; Heterogeneous catalysis", "note": "\u00a9 2020 Nature Publishing Group. \n\nReceived 08 July 2019; Accepted 30 July 2020; Published 07 September 2020. \n\nThe TEM work was conducted using the facilities in the Electron Imaging Center at the California NanoSystems Institute at the University of California Los Angles and the Irvine Materials Research Institute at the University of California Irvine. C.C., J.C., X.D. and Y.H. acknowledge support from the Office of Naval Research (ONR) under grant no. N000141712608. S.K., T.C. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award no. DE-SC0004993. C.L., S.K. and H.M.L. used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant no. ACI-1548562. C.L. and H.M.L. were also supported by a National Research Foundation (NRF) of Korea grant funded by the Korean Government (no. NRF-2017R1E1A1A03071049). The work done at the University of California Irvine was supported by the Irvine Materials Research Institute and ExxonMobil. \n\nData availability: The data that support the findings of this study are available from the corresponding authors upon reasonable request. \n\nAuthor Contributions: C.C. designed and conducted most of the experiments, analysed all the data and prepared the manuscript. S.K., T.C. and W.A.G. performed the density theoretical calculations and prepared the manuscript. M.X., P.T. and X.P. took SEI and bright-field scanning transmission electron microscopy images. J.C., C.L., H.M.L and X.D. assisted in the experiments and the preparation of the manuscript. Y.H. initiated the study, oversaw the project and wrote the manuscript. All the authors discussed the results and contributed to the manuscript. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41929_2020_504_MOESM1_ESM.pdf
Supplemental Material - 41929_2020_504_MOESM2_ESM.txt
", "abstract": "Electrochemical CO\u2082 reduction to value-added chemical feedstocks is of considerable interest for renewable energy storage and renewable source generation while mitigating CO\u2082 emissions from human activity. Copper represents an effective catalyst in reducing CO\u2082 to hydrocarbons or oxygenates, but it is often plagued by a low product selectivity and limited long-term stability. Here we report that copper nanowires with rich surface steps exhibit a remarkably high Faradaic efficiency for C\u2082H\u2084 that can be maintained for over 200\u2009hours. Computational studies reveal that these steps are thermodynamically favoured compared with Cu(100) surface under the operating conditions and the stepped surface favours C\u2082 products by suppressing the C\u2081 pathway and hydrogen production.", "date": "2020-10", "date_type": "published", "publication": "Nature Catalysis", "volume": "3", "number": "10", "publisher": "Nature Publishing Group", "pagerange": "804-812", "id_number": "CaltechAUTHORS:20200723-121126169", "issn": "2520-1158", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200723-121126169", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141712608" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "National Research Foundation of Korea", "grant_number": "NRF-2017R1E1A1A03071049" }, { "agency": "Irvine Materials Research Institute" }, { "agency": "ExxonMobil" } ] }, "other_numbering_system": { "items": [ { "id": "1391", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41929-020-00504-x", "primary_object": { "basename": "41929_2020_504_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/8snf1-1v863/files/41929_2020_504_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41929_2020_504_MOESM2_ESM.txt", "url": "https://authors.library.caltech.edu/records/8snf1-1v863/files/41929_2020_504_MOESM2_ESM.txt" } ], "pub_year": "2020", "author_list": "Choi, Chungseok; Kwon, Soonho; et el." }, { "id": "https://authors.library.caltech.edu/records/q4n3y-8tm47", "eprint_id": 102655, "eprint_status": "archive", "datestamp": "2023-08-19 23:28:31", "lastmod": "2023-10-20 00:23:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" }, "orcid": "0000-0002-1763-5788" }, { "id": "Dreyer-C-E", "name": { "family": "Dreyer", "given": "Cyrus E." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Piezoelectric Electron-Phonon Interaction from Ab Initio Dynamical Quadrupoles: Impact on Charge Transport in Wurtzite GaN", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Physical Society. \n\nReceived 20 February 2020; accepted 27 August 2020; published 21 September 2020. \n\nV.\u2009J. thanks the Resnick Sustainability Institute at Caltech for fellowship support. J.\u2009P. acknowledges support by the Korea Foundation for Advanced Studies. This work was supported by the National Science Foundation under Grants No. DMR-1750613 for theory development and No. ACI-1642443 for code development. J.-J.\u2009Z. acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of some computational methods employed in this work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. C.\u2009E.\u2009D. acknowledges support from the National Science Foundation under Grant No. DMR-1918455. The Flatiron Institute is a division of the Simons Foundation. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevLett.125.136602.pdf
Submitted - 2002.08351.pdf
Supplemental Material - SuppInfo.pdf
", "abstract": "First-principles calculations of e\u2212ph interactions are becoming a pillar of electronic structure theory. However, the current approach is incomplete. The piezoelectric (PE) e\u2212ph interaction, a long-range scattering mechanism due to acoustic phonons in noncentrosymmetric polar materials, is not accurately described at present. Current calculations include short-range e\u2212ph interactions (obtained by interpolation) and the dipolelike Fr\u00f6lich long-range coupling in polar materials, but lack important quadrupole effects for acoustic modes and PE materials. Here we derive and compute the long-range e\u2212ph interaction due to dynamical quadrupoles, and apply this framework to investigate e\u2212ph interactions and the carrier mobility in the PE material wurtzite GaN. We show that the quadrupole contribution is essential to obtain accurate e\u2212ph matrix elements for acoustic modes and to compute PE scattering. Our work resolves the outstanding problem of correctly computing e\u2212ph interactions for acoustic modes from first principles, and enables studies of e\u2212ph coupling and charge transport in PE materials.", "date": "2020-09-25", "date_type": "published", "publication": "Physical Review Letters", "volume": "125", "number": "13", "publisher": "American Physical Society", "pagerange": "Art. No. 136602", "id_number": "CaltechAUTHORS:20200420-112051827", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200420-112051827", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1918455" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevLett.125.136602", "primary_object": { "basename": "2002.08351.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/2002.08351.pdf" }, "related_objects": [ { "basename": "PhysRevLett.125.136602.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/PhysRevLett.125.136602.pdf" }, { "basename": "SuppInfo.pdf", "url": "https://authors.library.caltech.edu/records/q4n3y-8tm47/files/SuppInfo.pdf" } ], "pub_year": "2020", "author_list": "Jhalani, Vatsal A.; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/e62n6-sva42", "eprint_id": 105197, "eprint_status": "archive", "datestamp": "2023-08-19 23:26:21", "lastmod": "2023-10-20 21:27:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chapovetsky-A", "name": { "family": "Chapovetsky", "given": "Alon" }, "orcid": "0000-0001-8095-8830" }, { "id": "Liu-Jeffrey-J", "name": { "family": "Liu", "given": "Jeffrey J." }, "orcid": "0000-0003-2147-6449" }, { "id": "Welborn-M", "name": { "family": "Welborn", "given": "Matthew" } }, { "id": "Luna-J-M", "name": { "family": "Luna", "given": "John M." } }, { "id": "Do-Thomas", "name": { "family": "Do", "given": "Thomas" } }, { "id": "Haiges-R", "name": { "family": "Haiges", "given": "Ralf" }, "orcid": "0000-0003-4151-3593" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Marinescu-S-C", "name": { "family": "Marinescu", "given": "Smaranda C." }, "orcid": "0000-0003-2106-8971" } ] }, "title": "Electronically Modified Cobalt Aminopyridine Complexes Reveal an Orthogonal Axis for Catalytic Optimization for CO\u2082 Reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: July 14, 2020; Published: August 31, 2020. \n\nThe research was primarily supported by the National Science Foundation (NSF) under the CAREER Award CHE-1555387 (experimental studies) and the Chemistry of Life Processes Program CHE-1611581 (theoretical studies). S.C.M. acknowledges additional support from the Alfred P. Sloan Foundation through a Sloan research fellowship, the University of Southern California (USC), and the USC Women in Science and Engineering program. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the DOE Office of Science under contract DE-AC02-05CH11231. M.W. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. We thank Alfred Sattelberger for helpful discussions. \n\nAccession Codes: CCDC 2016095\u20132016096 contain the supplementary crystallographic data for this paper. These data can be obtained free of charge via www.ccdc.cam.ac.uk/data_request/cif, or by emailing data_request@ccdc.cam.ac.uk, or by contacting The Cambridge Crystallographic Data Centre, 12 Union Road, Cambridge CB2 1EZ, UK; fax: +44 1223 336033. \n\nAuthor Contributions: The manuscript was written through contributions of all authors. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ic0c02086_si_001.pdf
", "abstract": "The design of effective electrocatalysts for carbon dioxide reduction requires understanding the mechanistic underpinnings governing the binding, reduction, and protonation of CO\u2082. A critical aspect to understanding and tuning these factors for optimal catalysis revolves around controlling the electronic environments of the primary and secondary coordination sphere. Herein we report a series of para-substituted cobalt aminopyridine macrocyclic catalysts 2\u20134 capable of carrying out the electrochemical reduction of CO\u2082 to CO. Under catalytic conditions, complexes 2\u20134, as well as the unsubstituted cobalt aminopyridine complex 1, exhibit i_(cat)/i_p values ranging from 144 to 781. Complexes 2 and 4 exhibit a pronounced precatalytic wave suggestive of an ECEC mechanism. A Hammett analysis reveals that ligand modifications with electron-donating groups enhance catalysis (\u03c1 < 0), indicative of positive charge buildup in the transition state. This trend also extends to the Co^(I/0) potential, where complexes possessing more negative E(CoI/0) reductions exhibit greater i_(cat)/i_p values. The reported modifications offer a synthetic lever to tune catalytic activity, orthogonal to our previous study of the role of pendant hydrogen bond donors.", "date": "2020-09-21", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "59", "number": "18", "publisher": "American Chemical Society", "pagerange": "13709-13718", "id_number": "CaltechAUTHORS:20200901-095615539", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200901-095615539", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1555387" }, { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "University of Southern California" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.inorgchem.0c02086", "primary_object": { "basename": "ic0c02086_si_001.pdf", "url": "https://authors.library.caltech.edu/records/e62n6-sva42/files/ic0c02086_si_001.pdf" }, "pub_year": "2020", "author_list": "Chapovetsky, Alon; Liu, Jeffrey J.; et el." }, { "id": "https://authors.library.caltech.edu/records/eg0bd-gsc78", "eprint_id": 103291, "eprint_status": "archive", "datestamp": "2023-08-19 23:21:45", "lastmod": "2023-10-20 15:52:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Park-Jinsoo", "name": { "family": "Park", "given": "Jinsoo" }, "orcid": "0000-0002-1763-5788" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Dreyer-C-E", "name": { "family": "Dreyer", "given": "Cyrus E." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Long-range quadrupole electron-phonon interaction from first principles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Physical Society. \n\nReceived 30 March 2020; accepted 29 May 2020; published 21 September 2020. \n\nJ.P. acknowledges support by the Korea Foundation for Advanced Studies. V.A.J. thanks the Resnick Sustainability Institute at Caltech for fellowship support. This work was supported by the National Science Foundation under Grants No. DMR-1750613 for theory development and No. ACI-1642443 for code development. J.-J.Z. acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of some computational methods employed in this work was supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. C.E.D. acknowledges support from the National Science Foundation under Grant No. DMR-1918455. The Flatiron Institute is a division of the Simons Foundation. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the US Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevB.102.125203.pdf
Submitted - 2003.13782.pdf
", "abstract": "Lattice vibrations in materials induce perturbations on the electron dynamics in the form of long-range (dipole and quadrupole) and short-range (octopole and higher) potentials. The dipole Fr\u00f6hlich term can be included in current first-principles electron-phonon (e-ph) calculations and is present only in polar materials. The quadrupole e-ph interaction is present in both polar and nonpolar materials, but currently it cannot be computed from first principles. Here we show an approach to compute the quadrupole e-ph interaction and include it in ab initio calculations of e-ph matrix elements. The accuracy of the approach is demonstrated by comparing with direct density functional perturbation theory calculations. We apply our method to silicon as a case of a nonpolar semiconductor and tetragonal PbTiO\u2083 as a case of a polar piezoelectric material. In both materials we find that the quadrupole term strongly impacts the e-ph matrix elements. Analysis of e-ph interactions for different phonon modes reveals that the quadrupole term mainly affects optical modes in silicon and acoustic modes in PbTiO\u2083, although the quadrupole term is needed for all modes to achieve quantitative accuracy. The effect of the quadrupole e-ph interaction on electron scattering processes and transport is shown to be important. Our approach enables accurate studies of e-ph interactions in broad classes of nonpolar, polar, and piezoelectric materials.", "date": "2020-09-15", "date_type": "published", "publication": "Physical Review B", "volume": "102", "number": "12", "publisher": "American Physical Society", "pagerange": "Art. No. 125203", "id_number": "CaltechAUTHORS:20200518-152636389", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200518-152636389", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Korea Foundation for Advanced Studies" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1918455" }, { "agency": "Simons Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.102.125203", "primary_object": { "basename": "2003.13782.pdf", "url": "https://authors.library.caltech.edu/records/eg0bd-gsc78/files/2003.13782.pdf" }, "related_objects": [ { "basename": "PhysRevB.102.125203.pdf", "url": "https://authors.library.caltech.edu/records/eg0bd-gsc78/files/PhysRevB.102.125203.pdf" } ], "pub_year": "2020", "author_list": "Park, Jinsoo; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/gk4wt-5vg02", "eprint_id": 104987, "eprint_status": "archive", "datestamp": "2023-08-19 23:20:04", "lastmod": "2023-10-20 21:01:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ozden-Adnan", "name": { "family": "Ozden", "given": "Adnan" }, "orcid": "0000-0002-6924-1967" }, { "id": "Li-Fengwang", "name": { "family": "Li", "given": "Fengwang" }, "orcid": "0000-0003-1531-2966" }, { "id": "Garc\u0131\u0301a-de-Arquer-F-Pelayo", "name": { "family": "Garc\u0131\u0301a de Arquer", "given": "F. Pelayo" }, "orcid": "0000-0003-2422-6234" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Wang-Yuhang", "name": { "family": "Wang", "given": "Yuhang" }, "orcid": "0000-0001-5336-5183" }, { "id": "Hung-Sung-Fu", "name": { "family": "Hung", "given": "Sung-Fu" } }, { "id": "Wang-Xue", "name": { "family": "Wang", "given": "Xue" } }, { "id": "Chen-Bin", "name": { "family": "Chen", "given": "Bin" }, "orcid": "0000-0002-2106-7664" }, { "id": "Li-Jun", "name": { "family": "Li", "given": "Jun" } }, { "id": "Wicks-Joshua", "name": { "family": "Wicks", "given": "Joshua" }, "orcid": "0000-0001-7819-1167" }, { "id": "Luo-Mingchuan", "name": { "family": "Luo", "given": "Mingchuan" } }, { "id": "Wang-Ziyun", "name": { "family": "Wang", "given": "Ziyun" }, "orcid": "0000-0002-2817-8367" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Sargent-Edward-H", "name": { "family": "Sargent", "given": "Edward H." }, "orcid": "0000-0003-0396-6495" }, { "id": "Sinton-David", "name": { "family": "Sinton", "given": "David" }, "orcid": "0000-0003-2714-6408" } ] }, "title": "High-Rate and Efficient Ethylene Electrosynthesis Using a Catalyst/Promoter/Transport Layer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 10, 2020; Accepted: August 6, 2020; Published: August 14, 2020. \n\nThis work was financially supported by the Ontario Research Fund: Research Excellence Program, the Natural Sciences and Engineering Research Council (NSERC) of Canada, the CIFAR Bio-Inspired Solar Energy program and the Joint Centre of Artificial Synthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE-SC0004993. X-ray absorption spectra were performed on SXRMB beamlines at the Canadian Light Source (CLS), which is supported by the Canada Foundation for Innovation, Natural Sciences and Engineering Research Council of Canada, the University of Saskatchewan, the Government of Saskatchewan, Western Economic Diversification Canada, the National Research Council Canada, and the Canadian Institutes of Health Research. The authors acknowledge Ontario Centre for the Characterization of Advanced Materials (OCCAM) for sample preparation and characterization facilities and thank Dr. Alexander H. Ip, Dr. Christine Gabardo and Mr. Colin P. O'Brien for useful discussions. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). J.L. acknowledges the Banting postdoctoral fellowship. D.S. acknowledges the NSERC E.W.R. Steacie Memorial Fellowship. \n\nAuthor Contributions: A.O. and F.L. contributed equally to this work. D.S. and E.H.S. supervised the project. A.O. conceived the idea and carried out the electrochemical experiments with advice from F.L.. A.T. and A.R.-H. synthesized and characterized the tetrahydro-phenanthrolinium. A.O. carried out Raman and EIS measurements. Y.W. and A.O. carried out SEM imaging. F.L. and S.F.H. designed the XAS measurements. S.-F.H. performed the XAS measurements. X.W. performed the NMR analysis and provided help in EIS measurements. B.C. and Y.W. performed the TEM analysis. J.W. performed XPS measurements. M.L., J.L., and Z.W. provided help in electrochemical experiments. A.O. and F.L. wrote the manuscript. F.P.G.A. provided help in manuscript writing. All authors discussed the results and assisted during manuscript preparation. \n\nThe authors declare no competing financial interest.\n\nSubmitted - Manuscript-clean-ACS.docx
Supplemental Material - nz0c01266_si_001.pdf
", "abstract": "Carbon dioxide (CO\u2082) electroreduction to valuable chemicals such as ethylene is an avenue to store renewable electricity and close the carbon cycle. Membrane electrode assembly (MEA) electrolyzers have attracted recent interest in light of their high stability and despite low productivity (a modest partial current density in CO\u2082-to-ethylene conversion of approximately 100 mA cm\u207b\u00b2). Here we present an adlayer functionalization catalyst design: a catalyst/tetrahydro-phenanthrolinium/ionomer (CTPI) interface in which the catalytically active copper is functionalized using a phenanthrolinium-derived film and a perfluorocarbon-based polymeric ionomer. We find, using electroanalytical tools and operando spectroscopies, that this hierarchical adlayer augments both the local CO\u2082 availability and the adsorption of the key reaction intermediate CO on the catalyst surface. Using this CTPI catalyst, we achieve an ethylene Faradaic efficiency of 66% at a partial current density of 208 mA cm\u207b\u00b2\u2014a 2-fold increase over the best prior MEA electrolyzer report\u2014and an improved full-cell energy efficiency of 21%.", "date": "2020-09-11", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "9", "publisher": "American Chemical Society", "pagerange": "2811-2818", "id_number": "CaltechAUTHORS:20200818-072409036", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200818-072409036", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ontario Research Fund-Research Excellence" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "University of Saskatchewan" }, { "agency": "Government of Saskatchewan" }, { "agency": "Western Economic Diversification Canada" }, { "agency": "National Research Council of Canada" }, { "agency": "Canadian Institutes of Health Research (CIHR)" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.0c01266", "primary_object": { "basename": "Manuscript-clean-ACS.docx", "url": "https://authors.library.caltech.edu/records/gk4wt-5vg02/files/Manuscript-clean-ACS.docx" }, "related_objects": [ { "basename": "nz0c01266_si_001.pdf", "url": "https://authors.library.caltech.edu/records/gk4wt-5vg02/files/nz0c01266_si_001.pdf" } ], "pub_year": "2020", "author_list": "Ozden, Adnan; Li, Fengwang; et el." }, { "id": "https://authors.library.caltech.edu/records/bxhz8-wd706", "eprint_id": 105298, "eprint_status": "archive", "datestamp": "2023-08-22 06:22:01", "lastmod": "2023-10-20 21:46:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Digdaya-Ibadillah-A", "name": { "family": "Digdaya", "given": "Ibadillah A." }, "orcid": "0000-0001-7349-0934" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Lin-Meng", "name": { "family": "Lin", "given": "Meng" }, "orcid": "0000-0001-7785-749X" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "A direct coupled electrochemical system for capture and conversion of CO\u2082 from oceanwater", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon capture and storage; Electrocatalysis; Energy", "note": "\u00a9 The Author(s) 2020. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 18 May 2020; Accepted 30 July 2020; Published 04 September 2020. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. M.L. acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, Grant P2ELP2_178290. The authors thank the support from Sempra Energy on the cost and energy analysis of CO\u2082 capture from oceanwater. The authors are grateful to Dr. Nathan F. Dalleska at Caltech for the ion chromatography characterization of the synthetic oceanwater. \n\nData availability: The data that support the findings of this study are available from the corresponding author upon reasonable request. \n\nCode availability: All code used in simulations supporting this article is available from M.L. \n\nAuthor Contributions: I.A.D., I.S. and C.X. developed the conceptual idea and designed the experiments. I.A.D. and I.S. executed the experiments. M.L. performed the multi-physics modeling and simulation. C.X. and H.A.A. advised and supervised the work. I.A.D., I.S., M.L., L.H., and C.X. interpreted the data and wrote the manuscript. W.-H.C. fabricated the Ag-GDE. All the authors contributed in the intellectual discussions and finalized the paper. \n\nThe authors declare no competing interests. \n\nPeer review information: Nature Communications thanks Thomas Burdyny, Matthew Eisaman and the other, anonymous, reviewer(s) for their contribution to the peer review of this work. Peer reviewer reports are available.\n\nPublished - s41467-020-18232-y.pdf
Supplemental Material - 41467_2020_18232_MOESM1_ESM.pdf
Supplemental Material - 41467_2020_18232_MOESM2_ESM.pdf
", "abstract": "Capture and conversion of CO\u2082 from oceanwater can lead to net-negative emissions and can provide carbon source for synthetic fuels and chemical feedstocks at the gigaton per year scale. Here, we report a direct coupled, proof-of-concept electrochemical system that uses a bipolar membrane electrodialysis (BPMED) cell and a vapor-fed CO\u2082 reduction (CO\u2082R) cell to capture and convert CO\u2082 from oceanwater. The BPMED cell replaces the commonly used water-splitting reaction with one-electron, reversible redox couples at the electrodes and demonstrates the ability to capture CO\u2082 at an electrochemical energy consumption of 155.4\u2009kJ\u2009mol\u207b\u00b9 or 0.98 kWh kg\u207b\u00b9 of CO\u2082 and a CO\u2082 capture efficiency of 71%. The direct coupled, vapor-fed CO\u2082R cell yields a total Faradaic efficiency of up to 95% for electrochemical CO\u2082 reduction to CO. The proof-of-concept system provides a unique technological pathway for CO\u2082 capture and conversion from oceanwater with only electrochemical processes.", "date": "2020-09-04", "date_type": "published", "publication": "Nature Communications", "volume": "11", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 4412", "id_number": "CaltechAUTHORS:20200909-135831840", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200909-135831840", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2ELP2_178290" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-020-18232-y", "pmcid": "PMC7474062", "primary_object": { "basename": "41467_2020_18232_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/bxhz8-wd706/files/41467_2020_18232_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2020_18232_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/bxhz8-wd706/files/41467_2020_18232_MOESM2_ESM.pdf" }, { "basename": "s41467-020-18232-y.pdf", "url": "https://authors.library.caltech.edu/records/bxhz8-wd706/files/s41467-020-18232-y.pdf" } ], "pub_year": "2020", "author_list": "Digdaya, Ibadillah A.; Sullivan, Ian; et el." }, { "id": "https://authors.library.caltech.edu/records/mfdwx-pw660", "eprint_id": 104531, "eprint_status": "archive", "datestamp": "2023-08-22 06:21:42", "lastmod": "2023-10-20 20:34:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Zhijiang", "name": { "family": "Wang", "given": "Zhijiang" }, "orcid": "0000-0001-9314-7922" }, { "id": "Yuan-Qi", "name": { "family": "Yuan", "given": "Qi" } }, { "id": "Shan-Jingjing", "name": { "family": "Shan", "given": "Jingjing" } }, { "id": "Jiang-Zhaohua", "name": { "family": "Jiang", "given": "Zhaohua" } }, { "id": "Xu-Ping", "name": { "family": "Xu", "given": "Ping" }, "orcid": "0000-0002-7984-776X" }, { "id": "Hu-Yongfeng", "name": { "family": "Hu", "given": "Yongfeng" } }, { "id": "Zhou-Jigang", "name": { "family": "Zhou", "given": "Jigang" }, "orcid": "0000-0001-6644-2862" }, { "id": "Wu-Lina", "name": { "family": "Wu", "given": "Lina" } }, { "id": "Niu-Zhuangzhuang", "name": { "family": "Niu", "given": "Zhuangzhuang" } }, { "id": "Sun-Jianmin", "name": { "family": "Sun", "given": "Jianmin" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Highly Selective Electrocatalytic Reduction of CO\u2082 into Methane on Cu\u2013Bi Nanoalloys", "ispublished": "pub", "full_text_status": "public", "keywords": "CO2 reduction reaction; Cu alloy; methane; DFT; faraday efficiency", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: April 25, 2020; Accepted: July 23, 2020; Published: July 23, 2020. \n\nThis work was supported by the National Natural Science Foundation of China (51572062, 81771903, and 21972034). This work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The computations used the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation Grant Number ACI-1053575. This work is also a project supported by the Fund for Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions. XAS analysis was performed at the Canadian Light Source, a national research facility of the University of Saskatchewan, which is supported by the Canada Foundation for Innovation (CFI), the Natural Sciences and Engineering Research Council (NSERC), the National Research Council (NRC), the Canadian Institutes of Health Research (CIHR), the Government of Saskatchewan, and the University of Saskatchewan. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz0c01261_si_001.pdf
", "abstract": "Methane (CH\u2084), the main component of natural gas, is one of the most valuable products facilitating energy storage via electricity conversion. However, the poor selectivity and high overpotential for CH\u2084 formation with metallic Cu catalysts prevent realistic applications. Introducing a second element to tune the electronic state of Cu has been widely used as an effective method to improve catalytic performance, but achieving high selectivity and activity toward CH\u2084 remains challenging. Here, we successfully synthesized Cu\u2013Bi NPs, which exhibit a CH\u2084 Faradaic efficiency (FE) as high as 70.6% at \u22121.2 V versus reversible hydrogen electrode (RHE). The FE of Cu\u2013Bi NPs has increased by approximately 25-fold compared with that of Cu NPs. DFT calculations showed that alloying Cu with Bi significantly decreases the formation energy of *COH formation, the rate-determining step, which explains the improved performance. Further analysis showed that Cu that has been partially oxidized because of electron withdrawal by Bi is the most possible active site.", "date": "2020-09-03", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "11", "number": "17", "publisher": "American Chemical Society", "pagerange": "7261-7266", "id_number": "CaltechAUTHORS:20200723-122438908", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200723-122438908", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "51572062" }, { "agency": "National Natural Science Foundation of China", "grant_number": "81771903" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21972034" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Priority Academic Program Development of Jiangsu Higher Education Institutions" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "National Research Council of Canada" }, { "agency": "Canadian Institutes of Health Research (CIHR)" }, { "agency": "Government of Saskatchewan" }, { "agency": "University of Saskatchewan" } ] }, "other_numbering_system": { "items": [ { "id": "1388", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.0c01261", "primary_object": { "basename": "jz0c01261_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mfdwx-pw660/files/jz0c01261_si_001.pdf" }, "pub_year": "2020", "author_list": "Wang, Zhijiang; Yuan, Qi; et el." }, { "id": "https://authors.library.caltech.edu/records/sbanf-s8t86", "eprint_id": 104264, "eprint_status": "archive", "datestamp": "2023-08-19 22:56:39", "lastmod": "2023-10-20 19:14:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Si Microwire-Array Photocathodes Decorated with Cu Allow CO\u2082 Reduction with Minimal Parasitic Absorption of Sunlight", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: June 21, 2020; Accepted: July 7, 2020; Published: July 7, 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. Fabrication of the Si microwire arrays was performed in the Kavli Nanoscience Institute (KNI) at Caltech, and we thank the KNI staff for their assistance during fabrication. XPS data were collected at the Molecular Materials Resource Center of the Beckman Institute. \n\nAuthor Contributions: Si \u03bcW sample fabrication, P.A.K.; Cu foil preparation, M.H.R.; investigation, P.A.K., M.H.R., and W.H.C.; writing, P.A.K., M.H.R., B.S.B., and N.S.L.; funding acquisition, N.S.L. and B.S.B.; supervision, N.S.L. and B.S.B. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c01334_si_001.pdf
", "abstract": "High loadings of Cu were integrated on the light-facing side of Si microwire arrays used under simulated sunlight for the photoelectrochemical reduction of CO\u2082 (aq) to hydrocarbons in 0.10 M KHCO\u2083 (aq). Radial-junction n\u207ap-Si microwire arrays decorated with Cu exhibited absolute photocurrent densities comparable to an uncovered Si surface. Moreover, with respect to a Cu foil electrode, the positive shift in the onset potential for hydrocarbon formation at n\u207ap-Si/Cu microwire arrays was equal to or greater than the photovoltage of the semiconductor alone. Selective electrodeposition of Cu on the tips and sidewalls of Si microwires was responsible for the minimal parasitic reflection and absorption exhibited by the catalyst, such that light-limited, absolute current densities >25 mA\u00b7cm\u207b\u00b2 were sustained for 48 h under simulated sunlight. Photoelectrodes prepared from semiconductors with low diode quality factors and electrocatalysts with large Tafel slopes are shown to benefit from increased microstructured surface area. Si microwire arrays are thus suitable for photoelectrochemical reactions requiring high loadings of metallic and reflective electrocatalysts.", "date": "2020-08-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "8", "publisher": "American Chemical Society", "pagerange": "2528-2534", "id_number": "CaltechAUTHORS:20200707-161346609", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200707-161346609", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acsenergylett.0c01334", "primary_object": { "basename": "nz0c01334_si_001.pdf", "url": "https://authors.library.caltech.edu/records/sbanf-s8t86/files/nz0c01334_si_001.pdf" }, "pub_year": "2020", "author_list": "Kempler, Paul A.; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/5y8dd-5x714", "eprint_id": 104358, "eprint_status": "archive", "datestamp": "2023-08-19 22:33:12", "lastmod": "2023-10-20 19:20:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Fan", "name": { "family": "Yang", "given": "Fan" } }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Plymale-N-T", "name": { "family": "Plymale", "given": "Noah T." }, "orcid": "0000-0003-2564-8009" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Evaluation of sputtered nickel oxide, cobalt oxide and nickel\u2013cobalt oxide on n-type silicon photoanodes for solar-driven O\u2082(g) evolution from water", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nReceived 8th April 2020; Accepted 26th June 2020; First published 30 Jun 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award DE-SC0004993 to the Joint Center for Artificial Photosynthesis (JCAP), a DOE funded Energy Innovation Hub. UV-vis absorption and Atomic Force Microscope studies were performed at the Molecular Materials Resource Center (MMRC) in the Beckman Institute at the California Institute of Technology. Paul Kempler and Weilai Yu are thanked for assistance with editing the manuscript. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d0ta03725g1.pdf
", "abstract": "Thin films of nickel oxide (NiO_x), cobalt oxide (CoO_x) and nickel\u2013cobalt oxide (NiCoO_x) were sputtered onto n-Si(111) surfaces to produce a series of integrated, protected Si photoanodes that did not require deposition of a separate heterogeneous electrocatalyst for water oxidation. The p-type transparent conductive oxides (p-TCOs) acted as multi-functional transparent, antireflective, electrically conductive, chemically stable coatings that also were active electrocatalysts for the oxidation of water to O\u2082(g). Relative to the formal potential for water oxidation to O\u2082, E^(o\u2032)(O\u2082/H\u2082O), under simulated Air Mass (AM)1.5 illumination the p-TCO-coated n-Si(111) photoanodes produced mutually similar open-circuit potentials of \u2212270 \u00b1 20 mV, but different photocurrent densities at E^(o\u2032)(O\u2082/H\u2082O), of 28 \u00b1 0.3 mA cm\u207b\u00b2 for NiO_x, 18 \u00b1 0.3 mA cm\u207b\u00b2 for CoO_x and 24 \u00b1 0.5 mA cm\u207b\u00b2 for NiCoO_x. The p-TCOs all provided protection from oxide growth for extended time periods, and produced stable photocurrent densities from n-Si in 1.0 M KOH(aq) (ACS grade) under potential control at E^(o\u2032)(O\u2082/H\u2082O) for >400 h of continuous operation under 100 mW cm\u22122 of simulated AM1.5 illumination.", "date": "2020-07-28", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "8", "number": "28", "publisher": "Royal Society of Chemistry", "pagerange": "13955-13963", "id_number": "CaltechAUTHORS:20200713-130247847", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200713-130247847", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d0ta03725g", "primary_object": { "basename": "d0ta03725g1.pdf", "url": "https://authors.library.caltech.edu/records/5y8dd-5x714/files/d0ta03725g1.pdf" }, "pub_year": "2020", "author_list": "Yang, Fan; Zhou, Xinghao; et el." }, { "id": "https://authors.library.caltech.edu/records/y5n4f-9b980", "eprint_id": 104072, "eprint_status": "archive", "datestamp": "2023-08-19 22:28:09", "lastmod": "2023-10-20 19:03:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Soo-Hong", "name": { "family": "Lee", "given": "Soo Hong" }, "orcid": "0000-0002-2734-9654" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Larson-David-M", "name": { "family": "Larson", "given": "David M." }, "orcid": "0000-0001-9634-9175" }, { "id": "Liu-Guiji", "name": { "family": "Liu", "given": "Guiji" }, "orcid": "0000-0002-3943-4119" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Drisdell-Walter-S", "name": { "family": "Drisdell", "given": "Walter S." }, "orcid": "0000-0002-8693-4562" } ] }, "title": "Correlating Oxidation State and Surface Area to Activity from Operando Studies of Copper CO Electroreduction Catalysts in a Gas-fed Device", "ispublished": "pub", "full_text_status": "public", "keywords": "Operando X-ray absorption spectroscopy, electrochemical CO reduction, oxide-derived\ncopper electrocatalyst, gas diffusion electrode, oxidation state", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: April 13, 2020; Revised: June 11, 2020; Published: June 25, 2020. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515. \n\nAuthor Contributions: S.H.L. and I.S. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs0c01670_si_001.pdf
", "abstract": "The rational design of high-performance electrocatalysts requires a detailed understanding of dynamic changes in catalyst properties, including oxidation states, surface area, and morphology under realistic working conditions. Oxide-derived Cu catalysts exhibit a remarkable selectivity toward multicarbon products for the electrochemical CO reduction reaction (CORR), but the exact role of the oxide remains elusive for explaining the performance enhancements. Here, we used operando X-ray absorption spectroscopy (XAS) coupled with simultaneous measurements of the catalyst activity and selectivity by gas chromatography (GC) to study the relationship between oxidation states of Cu-based catalysts and the activity for ethylene (C\u2082H\u2084) production in a CO gas-fed cell. By utilizing a custom-built XAS cell, oxidation states of Cu catalysts can be probed in device-relevant settings and under high current densities (>80 mA cm\u207b\u00b2) for the CORR. By employing an electrochemical oxidation process, we found that the Cu oxidation states and specific ion species do not correlate with C\u2082H\u2084 production. The difference in the CORR activity is also investigated in relation to electrochemical surface area (ECSA) changes. While the hydrogen evolution reaction (HER) activity is positively correlated to the ECSA changes, the increased C\u2082H\u2084 activity is not proportional to the ECSA. Ex situ characterization from microscopic techniques suggests that the changes in the C\u2082H\u2084 activity and selectivity may arise from a morphological transformation that evolves into a more active structure. These comprehensive results give rise to the development of a cell regeneration method that can restore the performance of the Cu catalyst without cell disassembly. Our study establishes a basis for the rational design of highly active electrocatalysts for broad-range reactions in a gas-fed device.", "date": "2020-07-17", "date_type": "published", "publication": "ACS Catalysis", "volume": "10", "number": "14", "publisher": "American Chemical Society", "pagerange": "8000-8011", "id_number": "CaltechAUTHORS:20200626-103612366", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200626-103612366", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.0c01670", "primary_object": { "basename": "cs0c01670_si_001.pdf", "url": "https://authors.library.caltech.edu/records/y5n4f-9b980/files/cs0c01670_si_001.pdf" }, "pub_year": "2020", "author_list": "Lee, Soo Hong; Sullivan, Ian; et el." }, { "id": "https://authors.library.caltech.edu/records/yncck-x6j92", "eprint_id": 104339, "eprint_status": "archive", "datestamp": "2023-08-19 22:24:10", "lastmod": "2023-10-20 19:19:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yu-Weilai", "name": { "family": "Yu", "given": "Weilai" }, "orcid": "0000-0002-9420-0702" }, { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Mueller-Thomas", "name": { "family": "Mueller", "given": "Thomas" } }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Atomic force microscopy: Emerging illuminated and operando techniques for solar fuel research", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 Published under license by AIP Publishing. \n\nSubmitted: 6 April 2020; Accepted: 5 June 2020; Published Online: 10 July 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The authors would like to thank the Beckman Institute at the California Institute of Technology for continuous support. \n\nAuthors' Contributions: W.Y. and H.J.F. contributed equally to this work. \n\nData Availability: The data that support the findings of this study are available within the article.\n\nPublished - 5.0009858.pdf
", "abstract": "Integrated photoelectrochemical devices rely on the synergy between components to efficiently generate sustainable fuels from sunlight. The micro- and/or nanoscale characteristics of the components and their interfaces often control critical processes of the device, such as charge-carrier generation, electron and ion transport, surface potentials, and electrocatalysis. Understanding the spatial properties and structure\u2013property relationships of these components can provide insight into designing scalable and efficient solar fuel components and systems. These processes can be probed ex situ or in situ with nanometer-scale spatial resolution using emerging scanning-probe techniques based on atomic force microscopy (AFM). In this Perspective, we summarize recent developments of AFM-based techniques relevant to solar fuel research. We review recent progress in AFM for (1) steady-state and dynamic light-induced surface photovoltage measurements; (2) nanoelectrical conductive measurements to resolve charge-carrier heterogeneity and junction energetics; (3) operando investigations of morphological changes, as well as surface electrochemical potentials, currents, and photovoltages in liquids. Opportunities for research include: (1) control of ambient conditions for performing AFM measurements; (2) in situ visualization of corrosion and morphological evolution of electrodes; (3) operando AFM techniques to allow nanoscale mapping of local catalytic activities and photo-induced currents and potentials.", "date": "2020-07-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "153", "number": "2", "publisher": "American Institute of Physics", "pagerange": "Art. No. 020902", "id_number": "CaltechAUTHORS:20200710-151813992", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200710-151813992", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/5.0009858", "primary_object": { "basename": "5.0009858.pdf", "url": "https://authors.library.caltech.edu/records/yncck-x6j92/files/5.0009858.pdf" }, "pub_year": "2020", "author_list": "Yu, Weilai; Fu, Harold J.; et el." }, { "id": "https://authors.library.caltech.edu/records/0n46z-ac620", "eprint_id": 102985, "eprint_status": "archive", "datestamp": "2023-08-22 05:20:20", "lastmod": "2023-10-20 00:40:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Zemin", "name": { "family": "Zhang", "given": "Zemin" } }, { "id": "Lindley-S-A", "name": { "family": "Lindley", "given": "Sarah A." } }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Han-Weihua", "name": { "family": "Han", "given": "Weihua" } }, { "id": "Xie-Erqing", "name": { "family": "Xie", "given": "Erqing" } }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Cooper-J-K", "name": { "family": "Cooper", "given": "Jason K." }, "orcid": "0000-0002-7953-4229" } ] }, "title": "Fermi Level Engineering of Passivation and Electron Transport Materials for p-Type CuBi\u2082O\u2084 Employing a High\u2010Throughput Methodology", "ispublished": "pub", "full_text_status": "public", "keywords": "fermi level engineering; high\u2010throughput methodology; passivation layer; p\u2010type semiconductor; solar photochemistry", "note": "\u00a9 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: January 31, 2020; Revised: March 17, 2020; Published online: May 4, 2020. \n\nZ.Z. and S.A.L. contributed equally to this work. This material was based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of U.S. Department of Energy under Award Number DE\u2010SC0004993. EDX mapping was performed at the Molecular Foundry, supported by the Office of Science, Office of Basic Energy Science, of the U.S. Department of Energy under Contract No. DE\u2010AC02\u201005CH11231. Z.Z. also acknowledges the Chinese scholarship council (CSC) for providing funding. \n\nThe authors declare no conflict of interest.\n\nSupplemental Material - adfm202000948-sup-0001-suppmat.pdf
", "abstract": "Metal oxide semiconductors are promising for solar photochemistry if the issues of excessive charge carrier recombination and material degradation can be resolved, which are both influenced by surface quality and interface chemistry. Coating the semiconductor with an overlayer to passivate surface states is a common remedial strategy but is less desirable than application of a functional coating that can improve carrier extraction and reduce recombination while mitigating corrosion. In this work, a data\u2010driven materials science approach utilizing high\u2010throughput methodologies, including inkjet printing and scanning droplet electrochemical cell measurements, is used to create and evaluate multi\u2010element coating libraries to discover new classes of candidate passivation and electron\u2010selective contact materials for p\u2010type CuBi\u2082O\u2084. The optimized overlayer (Cu_(1.5)TiO\u2082) improves the onset potential by 110 mV, the photocurrent by 2.8\u00d7, and the absorbed photon\u2010to\u2010current efficiency by 15.5% compared to non\u2010coated photoelectrodes. It is shown that these enhancements are related to reduced surface recombination through passivation of surface defect states as well as improved carrier extraction efficiency through Fermi level engineering. This work presents a generalizable, high\u2010throughput method to design and optimize passivation materials for a variety of semiconductors, providing a powerful platform for development of high\u2010performance photoelectrodes for incorporation into solar\u2010fuel generation systems.", "date": "2020-06-10", "date_type": "published", "publication": "Advanced Functional Materials", "volume": "30", "number": "24", "publisher": "Wiley", "pagerange": "Art. No. 2000948", "id_number": "CaltechAUTHORS:20200504-153132620", "issn": "1616-301X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200504-153132620", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010AC02\u201005CH11231" }, { "agency": "Chinese Scholarship Council" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/adfm.202000948", "primary_object": { "basename": "adfm202000948-sup-0001-suppmat.pdf", "url": "https://authors.library.caltech.edu/records/0n46z-ac620/files/adfm202000948-sup-0001-suppmat.pdf" }, "pub_year": "2020", "author_list": "Zhang, Zemin; Lindley, Sarah A.; et el." }, { "id": "https://authors.library.caltech.edu/records/0wga1-nev35", "eprint_id": 102941, "eprint_status": "archive", "datestamp": "2023-08-19 21:48:01", "lastmod": "2023-10-20 00:38:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combinatorial synthesis of oxysulfides in the lanthanum-bismuth-copper system", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial synthesis, oxysulfide, thermal processing, solar fuels", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 5, 2020; Revised: March 10, 2020; Published: April 30, 2020. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). \n\nAuthor Contributions: M.U. and L.Z. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - co0c00015_si_001.pdf
", "abstract": "Establishing synthesis methods for a target material constitutes a grand challenge in materials research, which is compounded with use-inspired specifications on the format of the material. Solar photochemistry using thin film materials is a promising technology for which many complex materials are being proposed, and the present work describes application of combinatorial methods to explore the synthesis of predicted La\u2013Bi\u2013Cu oxysulfide photocathodes, in particular alloys of LaCuOS and BiCuOS. The variation in concentration of three cations and two anions in thin film materials, and crystallization thereof, is achieved by a combination of reactive sputtering and thermal processes including reactive annealing and rapid thermal processing. Composition and structural characterization establish composition-processing-structure relationships that highlight the breadth of processing conditions required for synthesis of LaCuOS and BiCuOS. The relative irreducibility of La oxides and limited diffusion indicate the need for high temperature processing, which conflicts with the temperature limits for mitigating evaporation of Bi and S. Collectively the results indicate that alloys of these phases will require reactive annealing protocols that are uniquely tailored to each composition, motivating advancement of dynamic processing capabilities to further automate discovery of synthesis routes.", "date": "2020-06-08", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "22", "number": "6", "publisher": "American Chemical Society", "pagerange": "319-326", "id_number": "CaltechAUTHORS:20200430-151239863", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200430-151239863", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.0c00015", "primary_object": { "basename": "co0c00015_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0wga1-nev35/files/co0c00015_si_001.pdf" }, "pub_year": "2020", "author_list": "Umehara, Mitsutaro; Zhou, Lan; et el." }, { "id": "https://authors.library.caltech.edu/records/0fjhz-dpz46", "eprint_id": 103095, "eprint_status": "archive", "datestamp": "2023-08-22 05:18:35", "lastmod": "2023-10-20 00:46:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ye-Yifan", "name": { "family": "Ye", "given": "Yifan" } }, { "id": "Qian-Jin", "name": { "family": "Qian", "given": "Jin" }, "orcid": "0000-0002-0162-0477" }, { "id": "Yang-Hao", "name": { "family": "Yang", "given": "Hao" }, "orcid": "0000-0002-8241-6231" }, { "id": "Su-Hongyang", "name": { "family": "Su", "given": "Hongyang" } }, { "id": "Lee-Kyung-Jae", "name": { "family": "Lee", "given": "Kyung-Jae" } }, { "id": "Etxebarria-A", "name": { "family": "Etxebarria", "given": "Ane" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" } ] }, "title": "Synergy between Silver-Copper Surface Alloy Composition and Carbon Dioxide Adsorption and Activation", "ispublished": "pub", "full_text_status": "public", "keywords": "CO2 adsorption; CO2 activation; Surface reconstruction; Density Functional Theory (DFT); Ambient Pressure XPS (APXPS)", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 3, 2020; Accepted: May 8, 2020; Published: May 8, 2020. \n\nThis work was supported through the Office of Science, Office of Basic Energy Science (BES), of the US Department of Energy (DOE) under Award DE-SC0004993 to the Joint Center for Artificial Photosynthesis, DOE Energy Innovation Hubs. The Advanced Light Source was supported by the Director, Office of Science, Office of BES, of the US DOE under contract DE-AC02-05CH11231. H.Y. and H.S. gratefully acknowledge the China Scholarship Council (CSC, nos. 201608320161 and 201706340112) for financial support. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which was supported by the National Science Foundation grant number ACI-1548562. Y.Y., J.Q., and E.J.C. were partially supported by an Early Career Award in the Condensed Phase and Interfacial Molecular Science Program, in the Chemical Sciences Geosciences and Biosciences Division of the Office of Basic Energy Sciences of the U.S. Department of Energy under contract no. DE-AC02-05CH11231. T.C. and H.Y. thank the financial support by the National Natural Science Foundation of China (21975148), the Natural Science Foundation of Jiangsu Higher Education Institutions (SBK20190810), Jiangsu Province High-Level Talents (JNHB-106), and the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD). T.C. and H.Y. were supported by grants from startup supports of Soochow University and the Program for Jiangsu Specially-Appointed Professors to T.C. H.Y. thanks the China Postdoctoral Science Foundation (2019M660128) for financial support. This work was partly supported by the Collaborative Innovation Center of Suzhou Nano Science & Technology. \n\nAuthor Contributions: Y.Y., J.Q., and H.Y. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - am0c02057_si_001.pdf
", "abstract": "Bimetallic electrocatalysts provide a promising strategy for improving performance, especially in the enhancement of selectivity of CO\u2082 reduction reactions. However, the first step of CO\u2082 activation on bimetallic materials remains obscure. Considering bimetallic silver\u2013copper (AgCu) as an example, we coupled ambient pressure X-ray photoelectron spectroscopy (APXPS) and quantum mechanics (QM) to examine CO\u2082 adsorption and activation on AgCu exposed to CO\u2082 with and without H\u2082O at 298 K. The interplay between adsorbed species and the surface alloy composition of Cu and Ag is studied in atomic details. The APXPS experiment and density functional theory (DFT) calculations indicate that the clean sample has a Ag-rich surface layer. Upon adsorption of CO\u2082 and surface O, we found that it is thermodynamically more favorable to induce subsurface Cu atoms substitution for some surface Ag atoms, modifying the stability and activation of CO\u2082-related chemisorbed species. We further characterized this substitution effect by correlating the new adsorption species with the observed binding energy (BE) shift and intensity change in APXPS.", "date": "2020-06-03", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "12", "number": "22", "publisher": "American Chemical Society", "pagerange": "25374-25382", "id_number": "CaltechAUTHORS:20200511-094745730", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200511-094745730", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "China Scholarship Council", "grant_number": "201608320161" }, { "agency": "China Scholarship Council", "grant_number": "201706340112" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21975148" }, { "agency": "Natural Science Foundation of Jiangsu Higher Education Institutions", "grant_number": "SBK20190810" }, { "agency": "Jiangsu Province High-Level Talents", "grant_number": "JNHB-106" }, { "agency": "Jiangsu Higher Education Institutions" }, { "agency": "Soochow University" }, { "agency": "China Postdoctoral Science Foundation", "grant_number": "2019M660128" }, { "agency": "Suzhou Nano Science and Technology" } ] }, "other_numbering_system": { "items": [ { "id": "1381", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.0c02057", "primary_object": { "basename": "am0c02057_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0fjhz-dpz46/files/am0c02057_si_001.pdf" }, "pub_year": "2020", "author_list": "Ye, Yifan; Qian, Jin; et el." }, { "id": "https://authors.library.caltech.edu/records/8aks8-76f41", "eprint_id": 103312, "eprint_status": "archive", "datestamp": "2023-08-19 21:44:14", "lastmod": "2023-10-20 15:54:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Coridan-Robert-H", "name": { "family": "Coridan", "given": "Robert H." }, "orcid": "0000-0003-1916-4446" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Effects of bubbles on the electrochemical behavior of hydrogen-evolving Si microwire arrays oriented against gravity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 03 Feb 2020; Accepted 08 Apr 2020; First published 08 Apr 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. High-speed microscopy experiments were supported by the National Science Foundation under Grant No. 1732096 (R. H. C.). Fabrication of the Si microwire arrays was performed in the Kavli Nanoscience Institute (KNI) at Caltech, and we thank the KNI staff for their assistance during fabrication. We thank K. M. P. and B. S. B. for helpful discussions on experimental design. \n\nAuthor contributions: Conceptualization, P. A. K., and N. S. L.; Methodology, P. A. K., Investigation, P. A. K. and R. H. C.; Writing\u2014Original Draft, P. A. K. and N. S. L.; Writing\u2014Review & Editing, N. S. L., P. A. K., R. H. C.; Funding Acquisition, N. S. L. and R. H. C.; Supervision, N. S. L. \n\nThe authors declare no competing interests.\n\nSupplemental Material - d0ee00356e1.mp4
Supplemental Material - d0ee00356e2.pdf
Supplemental Material - d0ee00356e3.mp4
", "abstract": "The size-distribution, coverage, electrochemical impedance, and mass-transport properties of H\u2082 gas-bubble films were measured for both planar and microwire-array platinized n\u207a-Si cathodes performing the hydrogen-evolution reaction in 0.50 M H\u2082SO\u2084 (aq). Inverted, planar n\u207a-Si/Ti/Pt cathodes produced large, stationary bubbles which contributed to substantial increases in ohmic potential drops. In contrast, regardless of orientation, microwire array n\u207a-Si/Ti/Pt cathodes exhibited a smaller layer of bubbles on the surface, and the formation of bubbles did not substantially increase the steady-state overpotential for H\u2082 (g) production. Experiments using an electroactive tracer species indicated that even when oriented against gravity, bubbles enhanced mass transport at the electrode surface. Microconvection due to growing and coalescing bubbles dominated effects due to macroconvection of gliding bubbles on Si microwire array cathodes. Electrodes that maintained a large number of small bubbles on the surface simultaneously exhibited low concentrations of dissolved hydrogen and small ohmic potential drops, thus exhibiting the lowest steady-state overpotentials. The results indicate that microstructured electrodes can operate acceptably for unassisted solar-driven water splitting in the absence of external convection and can function regardless of the orientation of the electrode with respect to the gravitational force vector.", "date": "2020-06-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "13", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1808-1817", "id_number": "CaltechAUTHORS:20200519-103638391", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200519-103638391", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-1732096" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/d0ee00356e", "primary_object": { "basename": "d0ee00356e1.mp4", "url": "https://authors.library.caltech.edu/records/8aks8-76f41/files/d0ee00356e1.mp4" }, "related_objects": [ { "basename": "d0ee00356e2.pdf", "url": "https://authors.library.caltech.edu/records/8aks8-76f41/files/d0ee00356e2.pdf" }, { "basename": "d0ee00356e3.mp4", "url": "https://authors.library.caltech.edu/records/8aks8-76f41/files/d0ee00356e3.mp4" } ], "pub_year": "2020", "author_list": "Kempler, Paul A.; Coridan, Robert H.; et el." }, { "id": "https://authors.library.caltech.edu/records/ew3bm-az688", "eprint_id": 104325, "eprint_status": "archive", "datestamp": "2023-08-19 21:32:51", "lastmod": "2023-10-20 19:18:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cao-Jinshan", "name": { "family": "Cao", "given": "Jinshan" } }, { "id": "Cheng-Zhiqiang", "name": { "family": "Cheng", "given": "Zhiqiang" }, "orcid": "0000-0003-2824-9126" }, { "id": "Kang-Lijuan", "name": { "family": "Kang", "given": "Lijuan" } }, { "id": "Lin-Meng", "name": { "family": "Lin", "given": "Meng" }, "orcid": "0000-0001-7785-749X" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" } } ] }, "title": "Patterned nanofiber air filters with high optical transparency, robust mechanical strength, and effective PM_(2.5) capture capability", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. Attribution-NonCommercial 3.0 Unported (CC BY-NC 3.0) \n\nSubmitted 01 Mar 2020; Accepted 07 May 2020; First published\t27 May 2020. \n\nThis work is supported by Jilin Province Innovation Capacity Building Fund Project (2019C050-9), Jilin Provincial Department of Science and Technology Natural Science Foundation (20180101212JC) and Changchun Science and Technology Project (18DY023). \n\nThere are no conflicts to declare.\n\nPublished - d0ra01967d.pdf
Supplemental Material - d0ra01967d1.pdf
", "abstract": "PM_(2.5), due to its small particle size, strong activity, ease of the attachment of toxic substances and long residence time in the atmosphere, has a great impact on human health and daily production. In this work, we have presented patterned nanofiber air filters with high optical transparency, robust mechanical strength and effective PM_(2.5) capture capability. Here, to fabricate a transparency air filter by a facile electrospinning method, we chose three kinds of patterned wire meshes with micro-structures as negative receiver substrates and directly electrospun polymer fibers onto the supporting meshes. Compared with randomly oriented nanofibers (named \"RO NFs\" in this paper) and commercially available facemasks, the patterned air filters showed great mechanical properties, and the water contact angles on their surfaces were about 122\u2013143\u00b0 (the water contact angle for RO NFs was 81\u00b0). In addition, the patterned nanofibers exhibited high porosity (>80%), and their mean pore size was about 0.5838\u20130.8686 \u03bcm (the mean pore size of RO NFs was 0.4374 \u03bcm). The results indicate that the transparent patterned air filters have the best PM_(2.5) filtration efficiency of 99.99% at a high transmittance of \u223c69% under simulated haze pollution.", "date": "2020-05-27", "date_type": "published", "publication": "RSC Advances", "volume": "10", "number": "34", "publisher": "Royal Society of Chemistry", "pagerange": "20155-20161", "id_number": "CaltechAUTHORS:20200710-105128397", "issn": "2046-2069", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200710-105128397", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Jilin Province Innovation Capacity Building Fund", "grant_number": "2019C050-9" }, { "agency": "Jilin Provincial Department of Science and Technology Natural Science Foundation", "grant_number": "20180101212JC" }, { "agency": "Changchun Science and Technology", "grant_number": "18DY023" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d0ra01967d", "primary_object": { "basename": "d0ra01967d.pdf", "url": "https://authors.library.caltech.edu/records/ew3bm-az688/files/d0ra01967d.pdf" }, "related_objects": [ { "basename": "d0ra01967d1.pdf", "url": "https://authors.library.caltech.edu/records/ew3bm-az688/files/d0ra01967d1.pdf" } ], "pub_year": "2020", "author_list": "Cao, Jinshan; Cheng, Zhiqiang; et el." }, { "id": "https://authors.library.caltech.edu/records/t6jmn-kwn71", "eprint_id": 102532, "eprint_status": "archive", "datestamp": "2023-08-19 21:31:50", "lastmod": "2023-10-20 00:17:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tagliabue-G", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "DuChene-J-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Habib-A", "name": { "family": "Habib", "given": "Adela" } }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Hot Hole versus Hot Electron Transport at Copper/GaN Heterojunction Interfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "plasmonics, hot carriers, photodetection, hot holes, p-type GaN, copper", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: January 25, 2020; Accepted: April 14, 2020; Published: April 14, 2020. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. G.T. acknowledges support from the Swiss National Science Foundation through the Advanced Postdoc Mobility Fellowship, Grant No. P300P2_171417. A.H. and R.S. acknowledge startup funding from Rensselaer Polytechnic Institute. All theoretical calculations were performed at the Center for Computational Innovations at Rensselaer Polytechnic Institute. \n\nAuthor Contributions: G.T., J.S.D., and H.A.A. conceived of the idea and designed the experiments. G.T. performed all materials synthesis and device characterization. A.H. and R.S. performed all theoretical calculations. G.T. and J.S.D. wrote the manuscript with contributions from all authors. H.A.A. supervised the project. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nn0c00713_si_001.pdf
", "abstract": "Among all plasmonic metals, copper (Cu) has the greatest potential for realizing optoelectronic and photochemical hot-carrier devices, thanks to its CMOS compatibility and outstanding catalytic properties. Yet, relative to gold (Au) or silver (Ag), Cu has rarely been studied and the fundamental properties of its photoexcited hot carriers are not well understood. Here, we demonstrate that Cu nanoantennas on p-type gallium nitride (p-GaN) enable hot-hole-driven photodetection across the visible spectrum. Importantly, we combine experimental measurements of the internal quantum efficiency (IQE) with ab initio theoretical modeling to clarify the competing roles of hot-carrier energy and mean-free path on the performance of hot-hole devices above and below the interband threshold of the metal. We also examine Cu-based plasmonic photodetectors on corresponding n-type GaN substrates that operate via the collection of hot electrons. By comparing hot hole and hot electron photodetectors that employ the same metal/semiconductor interface (Cu/GaN), we further elucidate the relative advantages and limitations of these complementary plasmonic systems. In particular, we find that harnessing hot holes with p-type semiconductors is a promising strategy for plasmon-driven photodetection across the visible and ultraviolet regimes. Given the technological relevance of Cu and the fundamental insights provided by our combined experimental and theoretical approach, we anticipate that our studies will have a broad impact on the design of hot-carrier optoelectronic devices and plasmon-driven photocatalytic systems.", "date": "2020-05-26", "date_type": "published", "publication": "ACS Nano", "volume": "14", "number": "5", "publisher": "American Chemical Society", "pagerange": "5788-5797", "id_number": "CaltechAUTHORS:20200414-133115396", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200414-133115396", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" }, { "agency": "Rensselaer Polytechnic Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsnano.0c00713", "primary_object": { "basename": "nn0c00713_si_001.pdf", "url": "https://authors.library.caltech.edu/records/t6jmn-kwn71/files/nn0c00713_si_001.pdf" }, "pub_year": "2020", "author_list": "Tagliabue, Giulia; DuChene, Joseph S.; et el." }, { "id": "https://authors.library.caltech.edu/records/yxbvn-61w10", "eprint_id": 102940, "eprint_status": "archive", "datestamp": "2023-08-19 21:26:41", "lastmod": "2023-10-20 00:38:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Yalamanchili-S", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Conformal SnO_x heterojunction coatings for stabilized photoelectrochemical water oxidation using arrays of silicon microcones", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2020. \n\nReceived 29th January 2020. Accepted 19th April 2020. First published 30 Apr 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and in part by the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect those of NSF or DOE. Fabrication was performed in Kavli Nanoscience Institute (KNI) at Caltech, and we thank KNI staff for their assistance during fabrication. I. M. H acknowledges a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. We thank C. Garland for assistance with transmission-electron microscopy measurements. \n\nThere are no conflicts to declare.\n\nSupplemental Material - d0ta01144d1.pdf
", "abstract": "The efficiency of photoelectrodes towards fuel-forming reactions is strongly affected by surface-based charge recombination, charge-transfer losses, and parasitic light absorption by electrocatalysts. We report a protective tin oxide (SnO_x) layer formed by atomic-layer deposition that limits surface recombination at n-Si/SnO_x heterojunctions and produces \u223c620 mV of photovoltage on planar n-Si photoanodes. The SnO_x layer can be deposited conformally on high aspect-ratio three-dimensional structures such as Si microcone arrays. Atomic-level control of the SnO_x thickness enabled highly conductive contacts to electrolytes, allowing the direct electrodeposition of NiFeOOH, CoO_x, and IrO_x electrocatalysts for photoelectrochemical water oxidation with minimal parasitic absorption losses. SnO_x-coated n-Si microcone arrays coupled to electrodeposited catalysts exhibited photocurrent densities of \u223c42 mA cm\u207b\u00b2 and a photovoltage of \u223c490 mV under 100 mW cm\u207b\u00b2 of simulated solar illumination. The SnO_x layer can be integrated with amorphous TiO\u2082 to form a protective SnO_x/TiO\u2082 bilayer that exhibits the beneficial properties of both materials. Photoanodes coated with SnO_x/TiO\u2082 exhibited a similar photovoltage to that of SnO_x-coated photoanodes, and showed >480 h of stable photocurrent for planar photoelectrodes and >140 h of stable photocurrent for n-Si microcone arrays under continuous simulated solar illumination in alkaline electrolytes.", "date": "2020-05-14", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "8", "number": "18", "publisher": "Royal Society of Chemistry", "pagerange": "9292-9301", "id_number": "CaltechAUTHORS:20200430-151239546", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200430-151239546", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/d0ta01144d", "primary_object": { "basename": "d0ta01144d1.pdf", "url": "https://authors.library.caltech.edu/records/yxbvn-61w10/files/d0ta01144d1.pdf" }, "pub_year": "2020", "author_list": "Moreno-Hernandez, Ivan A.; Yalamanchili, Sisir; et el." }, { "id": "https://authors.library.caltech.edu/records/4y3nf-wxy97", "eprint_id": 102719, "eprint_status": "archive", "datestamp": "2023-08-19 21:25:51", "lastmod": "2023-10-20 00:26:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yalu", "name": { "family": "Chen", "given": "Yalu" }, "orcid": "0000-0002-0589-845X" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Atomistic Explanation of the Dramatically Improved Oxygen Reduction Reaction of Jagged Platinum Nanowires, 50 times better than Pt", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: December 8, 2019; Published: April 22, 2020. \n\nThis research was supported by ONR (N00014-18-1-2155). Y.C. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work uses the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant Number ACI-1053575, and the computational resources of Caltech High Performance Computing Center (HPC). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja9b13218_si_001.pdf
", "abstract": "Pt is the best catalyst for the oxygen reduction reactions (ORRs), but it is far too slow. Huang and co-workers showed that dealloying 5 nm Ni7Pt3 nanowires (NW) led to 2 nm pure Pt jagged NW (J-PtNW) with ORRs 50 times faster than Pt/C. They suggested that the undercoordinated surface Pt atoms, mechanical strain, and high electrochemically active surface area (ECSA) are the main contributors. We report here multiscale atomic simulations that further explain this remarkably accelerated ORR activity from an atomistic perspective. We used the ReaxFF reactive force field to convert the 5 nm Ni\u2087Pt\u2083 NW to the jagged 2 nm NW. We applied quantum mechanics to find that 14.4% of the surface sites are barrierless for O_(ads) + H\u2082O_(ads) \u2192 2OH_(ads), the rate-determining step (RDS). The reason is that the concave nature of many surface sites pushes the OH bond of the H\u2082O_(ads) close to the O_(ads), leading to a dramatically reduced barrier. We used this observation to predict the performance improvement of the J-PtNW relative to Pt (111). Assuming every surface site reacts independently with this predicted rate leads to a 212-fold enhancement at 298.15 K, compared to 50 times experimentally. The atomic structures of the active sites provide insights for designing high-performance electrocatalysts for ORR.", "date": "2020-05-13", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "142", "number": "19", "publisher": "American Chemical Society", "pagerange": "8625-8632", "id_number": "CaltechAUTHORS:20200422-125311157", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200422-125311157", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-18-1-2155" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1378", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.9b13218", "primary_object": { "basename": "ja9b13218_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4y3nf-wxy97/files/ja9b13218_si_001.pdf" }, "pub_year": "2020", "author_list": "Chen, Yalu; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/j30z7-ass97", "eprint_id": 102193, "eprint_status": "archive", "datestamp": "2023-08-19 21:23:52", "lastmod": "2023-10-19 23:56:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "On the successes and opportunities for discovery of metal oxide photoanodes for solar fuels generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: January 10, 2020; Accepted: March 31, 2020; Published: March 31, 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c00067_si_001.pdf
", "abstract": "The importance of metal oxide photoanodes in solar fuels technology has garnered concerted efforts in photoanode discovery in recent decades, which complement parallel efforts in development of analytical techniques and optimization strategies using standard photoanodes such as TiO\u2082, Fe2O\u2083 and BiVO\u2084. Theoretical guidance of high throughput experiments has been particularly effective in dramatically increasing the portfolio of metal oxide photoanodes, motivating a new era of photoanode development where the characterization and optimization techniques developed on traditional materials are applied to nascent photoanodes that exhibit visible light photoresponse. The compendium of metal oxide photoanodes presented in the present work can also serve as the basis for further technique development, with a primary goal to establish workflows for discovery of materials that perform better against the critical criteria of operational stability, visible light photoresponse, and photovoltage suitable for tandem absorber architectures.", "date": "2020-05-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "5", "publisher": "American Chemical Society", "pagerange": "1413-1421", "id_number": "CaltechAUTHORS:20200331-093744929", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200331-093744929", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.0c00067", "primary_object": { "basename": "nz0c00067_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j30z7-ass97/files/nz0c00067_si_001.pdf" }, "pub_year": "2020", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/hwv5q-9xz07", "eprint_id": 103091, "eprint_status": "archive", "datestamp": "2023-08-19 21:23:29", "lastmod": "2023-10-20 00:46:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hossain-Md-Delowar", "name": { "family": "Hossain", "given": "Md Delowar" }, "orcid": "0000-0003-3440-8306" }, { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Yu-Ted-H", "name": { "family": "Yu", "given": "Ted H." }, "orcid": "0000-0003-3202-0981" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Luo-Zhengtang", "name": { "family": "Luo", "given": "Zhengtang" }, "orcid": "0000-0002-5134-9240" } ] }, "title": "Reaction mechanism and kinetics for CO\u2082 reduction on nickel single atom catalysts from quantum mechanics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2020. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 30 September 2019; Accepted 07 April 2020; Published 07 May 2020. \n\nThis project was supported by the Research Grant Council of Hong Kong SAR (Project numbers 16204818), NSFC-RGC Joint Research Scheme (N_HKUST607/17), the Innovation and Technology Commission (ITC-CNERC14SC01), the Guangzhou Science & Technology (Project 201704030134). This work was also supported by the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The calculations were performed on computer clusters at the materials and process simulation center (MSC) at Caltech, the high-performance computing (HPC) facility at Caltech, and the HKUST (funded by the School of Engineering). \n\nData availability: The data that support the findings of this study are available from the corresponding author upon request. \n\nAuthor Contributions: M.D.H., W.A.G., and Z.T.L. conceived the idea and designed the research. M.D.H. performed all the calculations. M.D.H., Y.H., and T.H.Y. participated in discussions analyzing the data obtained from the calculations. M.D.H., W.A.G., and Z.T.L. wrote the paper with helpful comments from Y.H. and T.H.Y. \n\nThe authors declare no competing interests.\n\nPublished - s41467-020-16119-6.pdf
Supplemental Material - 41467_2020_16119_MOESM1_ESM.pdf
Supplemental Material - 41467_2020_16119_MOESM2_ESM.docx
Supplemental Material - 41467_2020_16119_MOESM3_ESM.pdf
", "abstract": "Experiments have shown that graphene-supported Ni-single atom catalysts (Ni-SACs) provide a promising strategy for the electrochemical reduction of CO\u2082 to CO, but the nature of the Ni sites (Ni-N\u2082C\u2082, Ni-N\u2083C\u2081, Ni-N\u2084) in Ni-SACs has not been determined experimentally. Here, we apply the recently developed grand canonical potential kinetics (GCP-K) formulation of quantum mechanics to predict the kinetics as a function of applied potential (U) to determine faradic efficiency, turn over frequency, and Tafel slope for CO and H\u2082 production for all three sites. We predict an onset potential (at 10\u2009mA\u2009cm\u207b\u00b2) U_(onset)\u2009=\u2009\u22120.84\u2009V (vs. RHE) for Ni-N\u2082C\u2082 site and U_(onset)\u2009=\u2009\u22120.92\u2009V for Ni-N\u2083C\u2081 site in agreement with experiments, and U_(onset)\u2009=\u2009\u22121.03\u2009V for Ni-N\u2084. We predict that the highest current is for Ni-N\u2084, leading to 700\u2009mA\u2009cm\u207b\u00b2 at U\u2009=\u2009\u22121.12\u2009V. To help determine the actual sites in the experiments, we predict the XPS binding energy shift and CO vibrational frequency for each site.", "date": "2020-05-07", "date_type": "published", "publication": "Nature Communications", "volume": "11", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2256", "id_number": "CaltechAUTHORS:20200511-085432577", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200511-085432577", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Research Grant Council of Hong Kong", "grant_number": "16204818" }, { "agency": "National Natural Science Foundation of China", "grant_number": "N_HKUST607/17" }, { "agency": "Innovation and Technology Commission (Hong Kong)", "grant_number": "ITC-CNERC14SC01" }, { "agency": "Guangzhou Science and Technology Plan", "grant_number": "201704030134" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1376", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-020-16119-6", "pmcid": "PMC7205999", "primary_object": { "basename": "41467_2020_16119_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/hwv5q-9xz07/files/41467_2020_16119_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2020_16119_MOESM2_ESM.docx", "url": "https://authors.library.caltech.edu/records/hwv5q-9xz07/files/41467_2020_16119_MOESM2_ESM.docx" }, { "basename": "41467_2020_16119_MOESM3_ESM.pdf", "url": "https://authors.library.caltech.edu/records/hwv5q-9xz07/files/41467_2020_16119_MOESM3_ESM.pdf" }, { "basename": "s41467-020-16119-6.pdf", "url": "https://authors.library.caltech.edu/records/hwv5q-9xz07/files/s41467-020-16119-6.pdf" } ], "pub_year": "2020", "author_list": "Hossain, Md Delowar; Huang, Yufeng; et el." }, { "id": "https://authors.library.caltech.edu/records/3k5vv-8sc48", "eprint_id": 102022, "eprint_status": "archive", "datestamp": "2023-08-19 21:04:11", "lastmod": "2023-10-20 22:21:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sato-Shunsuke", "name": { "family": "Sato", "given": "Shunsuke" }, "orcid": "0000-0001-8178-7367" }, { "id": "McNicholas-B-J", "name": { "family": "McNicholas", "given": "Brendon J." }, "orcid": "0000-0002-3654-681X" }, { "id": "Grubbs-R-H", "name": { "family": "Grubbs", "given": "Robert H." }, "orcid": "0000-0002-0057-7817" } ] }, "title": "Aqueous electrocatalytic CO\u2082 reduction using metal complexes dispersed in polymer ion gels", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nSubmitted 01 Feb 2020; Accepted 11 Mar 2020; First published 16 Mar 2020. \n\nThis study was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of energy under Award Number DE-SC0004993. The authors would like to thank, N. F. Dalleska for GC-MS experimental support.\n\nSupplemental Material - d0cc00791a1_si.pdf
Erratum - d0cc90165b.pdf
", "abstract": "We use fac-[Re(bpy)(CO)\u2083Cl] ([Re\u2013Cl]) dispersed in polymer ion gel (PIG) ([Re]\u2013PIG) to carry out electrocatalytic CO\u2082 reduction in water. Electrolysis at \u22120.68 V vs. RHE in a CO\u2082-saturated KOH and K\u2082CO\u2083 solution produces CO with over 90% Faradaic efficiency. The PIG electrode is readily combined with water oxidation catalysts to generate a full electrochemical cell. Additionally, we provide evidence that the PIG electrode can be implemented with other molecular catalysts.", "date": "2020-04-25", "date_type": "published", "publication": "Chemical Communications", "volume": "56", "number": "32", "publisher": "Royal Society of Chemistry", "pagerange": "4440-4443", "id_number": "CaltechAUTHORS:20200320-095812618", "issn": "1359-7345", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200320-095812618", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/d0cc00791a", "primary_object": { "basename": "d0cc00791a1_si.pdf", "url": "https://authors.library.caltech.edu/records/3k5vv-8sc48/files/d0cc00791a1_si.pdf" }, "related_objects": [ { "basename": "d0cc90165b.pdf", "url": "https://authors.library.caltech.edu/records/3k5vv-8sc48/files/d0cc90165b.pdf" } ], "pub_year": "2020", "author_list": "Sato, Shunsuke; McNicholas, Brendon J.; et el." }, { "id": "https://authors.library.caltech.edu/records/b8ame-xhh49", "eprint_id": 101999, "eprint_status": "archive", "datestamp": "2023-08-19 20:55:48", "lastmod": "2023-10-19 23:43:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Kun", "name": { "family": "Jiang", "given": "Kun" }, "orcid": "0000-0003-3148-5058" }, { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Zeng-Guosong", "name": { "family": "Zeng", "given": "Guosong" } }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Bell-Alexis-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" } ] }, "title": "Effects of Surface Roughness on the Electrochemical Reduction of CO\u2082 over Cu", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 29, 2020; Accepted: March 19, 2020; Published: March 19, 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. K.J. acknowledges the startup funding from Shanghai Jiao Tong University. We also acknowledge Ms. Lien-Chun Weng, Dr. Zhou Lin, and Prof. Martin Head-Gordon for insightful discussions. \n\nAuthor Contributions: K.J. and Y.H. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c00482_si_001.pdf
Supplemental Material - nz0c00482_si_002.mp4
", "abstract": "We have investigated the role of surface roughening on the CO\u2082 reduction reaction (CO\u2082RR) over Cu. The activity and product selectivity of Cu surfaces roughened by plasma pretreatment in Ar, O\u2082, or N\u2082 were compared with that of electrochemically polished Cu samples. Differences in total and product current densities, the ratio of current densities for HER (the hydrogen evolution reaction) to CO\u2082RR, and the ratio of current densities for C\u2082\u208a to C\u2081 products depend on the electrochemically active surface and are nearly independent of plasma composition. Theoretical analysis of an electropolished and roughened Cu surface reveals a higher fraction of undercoordinated Cu sites on the roughened surface, sites that bind CO preferentially. Roughened surfaces also contain square sites similar to those on a Cu(100) surface but with neighboring step sites, which adsorb OC\u2013COH, a precursor to C\u2082\u208a products. These findings explain the increases in the formation of oxygenates and hydrocarbons relative to CO and the ratio of oxygenates to hydrocarbons observed with increasing surface roughness.", "date": "2020-04-10", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "4", "publisher": "American Chemical Society", "pagerange": "1206-1214", "id_number": "CaltechAUTHORS:20200319-124814828", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200319-124814828", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Shanghai Jiao Tong University" } ] }, "other_numbering_system": { "items": [ { "id": "1373", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.0c00482", "primary_object": { "basename": "nz0c00482_si_001.pdf", "url": "https://authors.library.caltech.edu/records/b8ame-xhh49/files/nz0c00482_si_001.pdf" }, "related_objects": [ { "basename": "nz0c00482_si_002.mp4", "url": "https://authors.library.caltech.edu/records/b8ame-xhh49/files/nz0c00482_si_002.mp4" } ], "pub_year": "2020", "author_list": "Jiang, Kun; Huang, Yufeng; et el." }, { "id": "https://authors.library.caltech.edu/records/7s8vj-hpt40", "eprint_id": 101944, "eprint_status": "archive", "datestamp": "2023-08-19 20:54:31", "lastmod": "2023-10-19 23:40:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Lublow-M", "name": { "family": "Lublow", "given": "Michael" } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Genesis and Propagation of Fractal Structures During Photoelectrochemical Etching of n-Silicon", "ispublished": "pub", "full_text_status": "public", "keywords": "Fractal structures, Silicon, Photoelectrochemistry, Photoelectron spectroscopy", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: December 18, 2019; Accepted: March 16, 2020; Published: March 16, 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. HJL is grateful for support by DFG project Le1192-4. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. Dedicated to the memory of Hans-Joachim Lewerenz. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - am9b22900_si_001.pdf
Supplemental Material - am9b22900_si_002.mp4
", "abstract": "The genesis, propagation, and dimensions of fractal-etch patterns that form anodically on front- or back-illuminated n-Si(100) photoelectrodes in contact with 11.9 M NH\u2084F(aq) has been investigated during either linear-sweep voltammetry or when the electrode was held at a constant potential (E = +6.0 V versus Ag/AgCl). Optical images collected in situ during electrochemical experiments revealed the location and underlying mechanism of initiation and propagation of the structures on the surface. X-ray photoelectron spectroscopic (XPS) data collected for samples emersed from the electrolyte at varied times provided detailed information about the chemistry of the surface during fractal etching. The fractal structure was strongly influenced by the orientation of the crystalline Si sample. The etch patterns were initially generated at points along the circumference of bubbles that formed upon immersion of n-Si(100) samples in the electrolyte, most likely due to the electrochemical and electronic isolation of areas beneath bubbles. XPS data showed the presence of a tensile-stressed silicon surface throughout the etching process as well as the presence of SiO_xF_y on the surface. The two-dimensional fractal dimension D_(f,2D) of the patterns increased with etching time to a maximum observed value of D_(f,2D)=1.82. Promotion of fractal etching near etch masks that electrochemically and electronically isolated areas of the photoelectrode surface enabled the selective placement of highly branched structures at desired locations on an electrode surface.", "date": "2020-04-08", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "12", "number": "14", "publisher": "American Chemical Society", "pagerange": "17018-17028", "id_number": "CaltechAUTHORS:20200317-132013328", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200317-132013328", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "Le1192-4" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.9b22900", "primary_object": { "basename": "am9b22900_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7s8vj-hpt40/files/am9b22900_si_001.pdf" }, "related_objects": [ { "basename": "am9b22900_si_002.mp4", "url": "https://authors.library.caltech.edu/records/7s8vj-hpt40/files/am9b22900_si_002.mp4" } ], "pub_year": "2020", "author_list": "Richter, Matthias H.; Lublow, Michael; et el." }, { "id": "https://authors.library.caltech.edu/records/5htxd-c1q08", "eprint_id": 101732, "eprint_status": "archive", "datestamp": "2023-08-19 20:54:18", "lastmod": "2023-10-19 22:59:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Li-Xueqian", "name": { "family": "Li", "given": "Xueqian" }, "orcid": "0000-0002-1197-3743" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Optical Excitation of a Nanoparticle Cu/p-NiO Photocathode Improves Reaction Selectivity for CO\u2082 Reduction in Aqueous Electrolytes", "ispublished": "pub", "full_text_status": "public", "keywords": "artificial photosynthesis, photoelectrochemistry, hot holes, plasmonic\nphotocathode, CO2 reduction", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: November 25, 2019; Revised: March 3, 2020; Published: March 5, 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. G.T. acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, grant no. P2EZP2_159101, and the Advanced Mobility Fellowship, grant no. P300P2_171417. A.J.W. acknowledges support from the Resnick Sustainability Institute at the California Institute of Technology and the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 1745301. We thank Professor Brian McCloskey for sharing the design of the photoelectrochemical cell for temperature-controlled CO\u2082 reduction experiments. We also thank Dr. Matthias Richter for XPS characterization of p-type NiO and Cu/p-NiO films, which was performed at the Molecular Materials Research Center in the Beckman Institute of the California Institute of Technology. \n\nAuthor Contributions: J.S.D. and H.A.A. conceived the idea, designed the experiments, and wrote the manuscript. J.S.D. performed all photoelectrochemical experiments with assistance from A.J.W. and X.L. J.S.D., G.T., A.J.W., and X.L. fabricated and characterized devices. W.-H.C. performed optical characterization of materials and assisted with calibration and maintenance of gas chromatography equipment. H.A.A. supervised the project. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nl9b04895_si_001.pdf
", "abstract": "We report the light-induced modification of catalytic selectivity for photoelectrochemical CO\u2082 reduction in aqueous media using copper (Cu) nanoparticles dispersed onto p-type nickel oxide (p-NiO) photocathodes. Optical excitation of Cu nanoparticles generates hot electrons available for driving CO\u2082 reduction on the Cu surface, while charge separation is accomplished by hot-hole injection from the Cu nanoparticles into the underlying p-NiO support. Photoelectrochemical studies demonstrate that optical excitation of plasmonic Cu/p-NiO photocathodes imparts increased selectivity for CO\u2082 reduction over hydrogen evolution in aqueous electrolytes. Specifically, we observed that plasmon-driven CO\u2082 reduction increased the production of carbon monoxide and formate, while simultaneously reducing the evolution of hydrogen. Our results demonstrate an optical route toward steering the selectivity of artificial photosynthetic systems with plasmon-driven photocathodes for photoelectrochemical CO\u2082 reduction in aqueous media.", "date": "2020-04-08", "date_type": "published", "publication": "Nano Letters", "volume": "20", "number": "4", "publisher": "American Chemical Society", "pagerange": "2348-2358", "id_number": "CaltechAUTHORS:20200305-145718553", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200305-145718553", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.9b04895", "primary_object": { "basename": "nl9b04895_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5htxd-c1q08/files/nl9b04895_si_001.pdf" }, "pub_year": "2020", "author_list": "DuChene, Joseph S.; Tagliabue, Giulia; et el." }, { "id": "https://authors.library.caltech.edu/records/4xrqs-g9f79", "eprint_id": 109780, "eprint_status": "archive", "datestamp": "2023-08-19 20:54:08", "lastmod": "2023-10-20 22:21:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gauthier-Joseph-A", "name": { "family": "Gauthier", "given": "Joseph A." }, "orcid": "0000-0001-9542-0988" }, { "id": "Chen-Leanne-D", "name": { "family": "Chen", "given": "Leanne D." }, "orcid": "0000-0001-9700-972X" }, { "id": "Bajdich-Michal", "name": { "family": "Bajdich", "given": "Michal" }, "orcid": "0000-0003-1168-8616" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" } ] }, "title": "Implications of the fractional charge of hydroxide at the electrochemical interface", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 the Owner Societies. \n\nSubmitted 01 Nov 2019; Accepted 14 Feb 2020; First published\t03 Mar 2020. \n\nThis work was performed under the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work uses computational resources at the Stanford Research Computing Center and also of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility, supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Some of the computing for this project was performed on the Sherlock cluster. KC acknowledges support by a research grant (9455) from VILLUM FONDEN. \n\nThere are no conflicts to declare.\n\nSubmitted - implications-of-the-fractional-charge-of-hydroxide-at-the-electrochemical-interface.pdf
Supplemental Material - c9cp05952k1.pdf
", "abstract": "Rational design of materials that efficiently convert electrical energy into chemical bonds will ultimately depend on a thorough understanding of the electrochemical interface at the atomic level. Towards this goal, the use of density functional theory (DFT) at the generalized gradient approximation (GGA) level has been applied widely in the past 15 years. In the calculation of electrochemical reaction energetics using GGA-DFT, it is frequently implicitly assumed that ions in the Helmholtz plane have unit charge. However, the ion charge is observed to be fractional near the interface through both a capacitor model and through Bader charge partitioning. In this work, we show that this spurious charge transfer can be effectively mitigated by continuum charging of the electrolyte. We then show that, similar to hydronium, the observed fractional charge of hydroxide is not due to a GGA level self-interaction error, as the partial charge is observed even when using hybrid level exchange\u2013correlation functionals.", "date": "2020-04-07", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "22", "number": "13", "publisher": "Royal Society of Chemistry", "pagerange": "6964-6969", "id_number": "CaltechAUTHORS:20210712-221642048", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210712-221642048", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Villum Foundation", "grant_number": "9455" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9cp05952k", "primary_object": { "basename": "c9cp05952k1.pdf", "url": "https://authors.library.caltech.edu/records/4xrqs-g9f79/files/c9cp05952k1.pdf" }, "related_objects": [ { "basename": "implications-of-the-fractional-charge-of-hydroxide-at-the-electrochemical-interface.pdf", "url": "https://authors.library.caltech.edu/records/4xrqs-g9f79/files/implications-of-the-fractional-charge-of-hydroxide-at-the-electrochemical-interface.pdf" } ], "pub_year": "2020", "author_list": "Gauthier, Joseph A.; Chen, Leanne D.; et el." }, { "id": "https://authors.library.caltech.edu/records/d8kbs-eg786", "eprint_id": 101846, "eprint_status": "archive", "datestamp": "2023-08-22 04:25:14", "lastmod": "2023-10-19 23:34:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yao-Yonggang", "name": { "family": "Yao", "given": "Yonggang" } }, { "id": "Huang-Zhennan", "name": { "family": "Huang", "given": "Zhennan" } }, { "id": "Li-Tangyuan", "name": { "family": "Li", "given": "Tangyuan" } }, { "id": "Wang-Hang", "name": { "family": "Wang", "given": "Hang" } }, { "id": "Liu-Yifan", "name": { "family": "Liu", "given": "Yifan" } }, { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Mao-Yimin", "name": { "family": "Mao", "given": "Yimin" } }, { "id": "Gao-Jinlong", "name": { "family": "Gao", "given": "Jinlong" } }, { "id": "Jiao-Miaolun", "name": { "family": "Jiao", "given": "Miaolun" } }, { "id": "Dong-Qi", "name": { "family": "Dong", "given": "Qi" } }, { "id": "Dai-Jiaqi", "name": { "family": "Dai", "given": "Jiaqi" } }, { "id": "Xie-Pengfei", "name": { "family": "Xie", "given": "Pengfei" } }, { "id": "Xie-Hua", "name": { "family": "Xie", "given": "Hua" } }, { "id": "Lacey-Steven-D", "name": { "family": "Lacey", "given": "Steven D." } }, { "id": "Takeuchi-Ichiro", "name": { "family": "Takeuchi", "given": "Ichiro" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Jiang-Rongzhong", "name": { "family": "Jiang", "given": "Rongzhong" } }, { "id": "Wang-Chao", "name": { "family": "Wang", "given": "Chao" } }, { "id": "Taylor-Andre-D", "name": { "family": "Taylor", "given": "Andre D." } }, { "id": "Shahbazian-Yassar-R", "name": { "family": "Shahbazian-Yassar", "given": "Reza" } }, { "id": "Hu-Liangbing", "name": { "family": "Hu", "given": "Liangbing" } } ] }, "title": "High-throughput, combinatorial synthesis of multimetallic nanoclusters", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial; high-throughput synthesis; multimetallic nanoclusters; thermal shock; oxygen reduction reaction", "note": "\u00a9 2020 the Author(s). Published by PNAS. This open access article is distributed under Creative Commons Attribution-NonCommercial-NoDerivatives License 4.0 (CC BY-NC-ND). \n\nEdited by Catherine J. Murphy, University of Illinois Urbana\u2013Champaign, Urbana, IL, and approved February 6, 2020 (received for review March 8, 2019). PNAS first published March 10, 2020. \n\nThis work was supported by the Maryland Nanocenter, its Surface Analysis Center, and the AIMLab. R.S.-Y. was supported by NSF Division of Materials Research Award 1809439. R.J. thanks the Electrochemistry Branch, Combat Capabilities Development Command Army Research Laboratory for helpful collaboration in electrocatalysis. Y.L. and C.W. were supported by the Young Investigator Program of the Army Research Office (Grant W911 NF-15-1-0123). Scanning droplet cell measurements were supported by the Office of Science of the US Department of Energy under Award DE-SC0004993. Y.M. thanks Peter Z. Zavalij for his helpful discussion. This research used resources of the Advanced Photon Source, a US Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Argonne National Laboratory under Contract DE-AC02-06CH11357. The identification of any commercial product or trade name does not imply endorsement or recommendation by the National Institute of Standards and Technology. \n\nData Availability: All data are available within the main text and SI Appendix. \n\nAuthor contributions: Y.Y. and L.H. designed research; Y.Y., Z.H., T.L., H.W., Y.L., Y.M., J.G., M.J., Q.D., P.X., H.X., S.D.L., and R.J. performed research; Z.H., H.S.S., Y.M., J.D., J.M.G., and R.S.-Y. contributed new reagents/analytic tools; Y.Y., T.L., H.W., Y.L., H.S.S., Y.M., J.G., M.J., Q.D., P.X., I.T., J.M.G., R.J., C.W., A.D.T., R.S.-Y., and L.H. analyzed data; Y.Y. and L.H. wrote the paper; and T.L., I.T., C.W., A.D.T., and R.S.-Y. revised the manuscript. \n\nY.Y., Z.H., T.L., and H.W. contributed equally to this work. \n\nThe authors declare no competing interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at https://www.pnas.org/lookup/suppl/doi:10.1073/pnas.1903721117/-/DCSupplemental.\n\nPublished - 6316.full.pdf
Supplemental Material - pnas.1903721117.sapp.pdf
Supplemental Material - pnas.1903721117.sm01.mov
", "abstract": "Multimetallic nanoclusters (MMNCs) offer unique and tailorable surface chemistries that hold great potential for numerous catalytic applications. The efficient exploration of this vast chemical space necessitates an accelerated discovery pipeline that supersedes traditional \"trial-and-error\" experimentation while guaranteeing uniform microstructures despite compositional complexity. Herein, we report the high-throughput synthesis of an extensive series of ultrafine and homogeneous alloy MMNCs, achieved by 1) a flexible compositional design by formulation in the precursor solution phase and 2) the ultrafast synthesis of alloy MMNCs using thermal shock heating (i.e., \u223c1,650 K, \u223c500 ms). This approach is remarkably facile and easily accessible compared to conventional vapor-phase deposition, and the particle size and structural uniformity enable comparative studies across compositionally different MMNCs. Rapid electrochemical screening is demonstrated by using a scanning droplet cell, enabling us to discover two promising electrocatalysts, which we subsequently validated using a rotating disk setup. This demonstrated high-throughput material discovery pipeline presents a paradigm for facile and accelerated exploration of MMNCs for a broad range of applications.", "date": "2020-03-24", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "117", "number": "12", "publisher": "National Academy of Sciences", "pagerange": "6316-6322", "id_number": "CaltechAUTHORS:20200310-155236320", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200310-155236320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Maryland Nanocenter" }, { "agency": "NSF", "grant_number": "DMR-1809439" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-15-1-0123" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1903721117", "pmcid": "PMC7104385", "primary_object": { "basename": "6316.full.pdf", "url": "https://authors.library.caltech.edu/records/d8kbs-eg786/files/6316.full.pdf" }, "related_objects": [ { "basename": "pnas.1903721117.sapp.pdf", "url": "https://authors.library.caltech.edu/records/d8kbs-eg786/files/pnas.1903721117.sapp.pdf" }, { "basename": "pnas.1903721117.sm01.mov", "url": "https://authors.library.caltech.edu/records/d8kbs-eg786/files/pnas.1903721117.sm01.mov" } ], "pub_year": "2020", "author_list": "Yao, Yonggang; Huang, Zhennan; et el." }, { "id": "https://authors.library.caltech.edu/records/37y1k-4kp94", "eprint_id": 100643, "eprint_status": "archive", "datestamp": "2023-08-22 04:21:34", "lastmod": "2023-10-23 16:14:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Rohr-Brian", "name": { "family": "Rohr", "given": "Brian" }, "orcid": "0000-0003-4696-0149" }, { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Aykol-Muratahan", "name": { "family": "Aykol", "given": "Muratahan" }, "orcid": "0000-0001-6433-7217" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Benchmarking the Acceleration of Materials Discovery by Sequential Learning", "ispublished": "pub", "full_text_status": "public", "keywords": "active learning; autonomous science; oxygen evolution reaction", "note": "\u00a9 2020 The Royal Society of Chemistry. This Open Access Article is licensed under a Creative Commons Attribution 3.0 Unported Licence. \n\nReceived 27th November 2019, Accepted 27th January 2020, First published on 29th January 2020. \n\nThis work was funded by Toyota Research Institute through the Accelerated Materials Design and Discovery program (machine learning and simulation of sequential learning); by the Joint Center for Artificial Photosynthesis, a US Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under Award Number DE-SC0004993 (data acquisition); and by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award DE-SC0020383 (data curation and establishment of baselines). \n\nData and code availability: All catalyst data is visualized in Fig. 2 or the ESI\u2020 and is available for interactive visualization and download at http://data.matr.io/ACE-I. Source code for benchmarking sequential learning runs against random sample selection and demonstrating the sequential learning is available at http://https://github.com/SantoshSuram-TRI/ACE-I. The compilation of data is available in that repository and also at http://https://data.caltech.edu/records/1345 (DOI: 10.22002/D1.1345). \n\nConflicts of interest: B. R., H. S., S. S. and J. G. filed a provisional patent application on active learning enabled experimental catalyst materials discovery: US app. no. 62/837,379. The remaining authors declare no competing interests.\n\nPublished - c9sc05999g.pdf
Submitted - benchmark_seq_learning_chemrxiv_submit1.pdf
Supplemental Material - c9sc05999g1_si.pdf
", "abstract": "Sequential learning (SL) strategies, i.e. iteratively updating a machine learning model to guide experiments, have been proposed to significantly accelerate materials discovery and research. Applications on computational datasets and a handful of optimization experiments have demonstrated the promise of SL, motivating a quantitative evaluation of its ability to accelerate materials discovery, specifically in the case of physical experiments. The benchmarking effort in the present work quantifies the performance of SL algorithms with respect to a breadth of research goals: discovery of any \"good\" material, discovery of all \"good\" materials, and discovery of a model that accurately predicts the performance of new materials. To benchmark the effectiveness of different machine learning models against these goals, we use datasets in which the performance of all materials in the search space is known from high-throughput synthesis and electrochemistry experiments. Each dataset contains all pseudo-quaternary metal oxide combinations from a set of six elements (chemical space), the performance metric chosen is the electrocatalytic activity (overpotential) for the oxygen evolution reaction (OER). A diverse set of SL schemes is tested on four chemical spaces, each containing 2121 catalysts. The presented work suggests that research can be accelerated by up to a factor of 20 compared to random acquisition in specific scenarios. The results also show that certain choices of SL models are ill-suited for a given research goal resulting in substantial deceleration compared to random acquisition methods. The results provide quantitative guidance on how to tune an SL strategy for a given research goal and demonstrate the need for a new generation of materials-aware SL algorithms to further accelerate materials discovery.", "date": "2020-03-14", "date_type": "published", "publication": "Chemical Science", "volume": "11", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2696-2706", "id_number": "CaltechAUTHORS:20200110-151145517", "issn": "2041-6520", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200110-151145517", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Toyota Research Institute" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0020383" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9sc05999g", "primary_object": { "basename": "benchmark_seq_learning_chemrxiv_submit1.pdf", "url": "https://authors.library.caltech.edu/records/37y1k-4kp94/files/benchmark_seq_learning_chemrxiv_submit1.pdf" }, "related_objects": [ { "basename": "c9sc05999g.pdf", "url": "https://authors.library.caltech.edu/records/37y1k-4kp94/files/c9sc05999g.pdf" }, { "basename": "c9sc05999g1_si.pdf", "url": "https://authors.library.caltech.edu/records/37y1k-4kp94/files/c9sc05999g1_si.pdf" } ], "pub_year": "2020", "author_list": "Rohr, Brian; Stein, Helge S.; et el." }, { "id": "https://authors.library.caltech.edu/records/ynj8h-ca285", "eprint_id": 101691, "eprint_status": "archive", "datestamp": "2023-08-19 20:33:35", "lastmod": "2023-10-19 22:57:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Dunn-Emily", "name": { "family": "Dunn", "given": "Emily" } }, { "id": "DuChene-J-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Bicarbonate or Carbonate Processes for Coupling Carbon Dioxide Capture and Electrochemical Conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: February 2, 2020; Accepted: February 26, 2020. Publication Date: March 3, 2020. \n\nThis work is done within the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number De-SC0004993. A.J.W. acknowledges support from the Resnick Sustainability Institute at Caltech for fellowship support and from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 174530. \n\nAuthor Contributions: A.J.W, J.S.D, and H.A.A. conceived the idea and examined the feasibility of such a process. A.J.W. and E.D. performed all of the calculations and research required to complete the energy analysis of various systems. J.S.D. advised throughout the process and provided valuable input for determining the viability of various proposed processes. A.J.W., J.S.D, and H.A.A. wrote the Viewpoint, and all authors commented on the manuscript. \n\nAny opinions, findings, and conclusions expressed in this material are those of the authors and do not necessary reflect those of DOE or NSF. Views expressed in this Viewpoint are those of the authors and not necessarily the views of the ACS. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz0c00234_si_001.pdf
", "abstract": "Designing a scalable system to capture CO\u2082 from the air and convert it into valuable chemicals, fuels, and materials could be transformational for mitigating climate change. Climate models predict that negative greenhouse gas emissions will be required by the year 2050 in order to stay below a 2 \u00b0C change in global temperature. The processes of CO\u2082 capture, CO\u2082 conversion, and finally product separation all require significant energy inputs; devising a system that simultaneously minimizes the energy required for all steps is an important challenge. To date, a variety of prototype or pilot-level CO\u2082 capture and/or conversion systems have been designed and built targeting the individual objectives of either capture or conversion. One approach has focused on CO\u2082 removal from the atmosphere and storage of pure pressurized CO\u2082. Other efforts have concentrated on CO\u2082 conversion processes, such as electrochemical reduction or fermentation. Only a few concepts or analyses have been developed for complete end-to-end processes that perform both CO\u2082 capture and transformation.", "date": "2020-03-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "3", "publisher": "American Chemical Society", "pagerange": "940-945", "id_number": "CaltechAUTHORS:20200304-074750016", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200304-074750016", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-174530" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.0c00234", "primary_object": { "basename": "nz0c00234_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ynj8h-ca285/files/nz0c00234_si_001.pdf" }, "pub_year": "2020", "author_list": "Welch, Alex J.; Dunn, Emily; et el." }, { "id": "https://authors.library.caltech.edu/records/0hch1-hpn96", "eprint_id": 101157, "eprint_status": "archive", "datestamp": "2023-08-22 04:19:47", "lastmod": "2023-10-19 22:29:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jeong-Hyung-Mo", "name": { "family": "Jeong", "given": "Hyung Mo" } }, { "id": "Kwon-Youngkook", "name": { "family": "Kwon", "given": "Youngkook" } }, { "id": "Won-Jong-Ho", "name": { "family": "Won", "given": "Jong Ho" } }, { "id": "Lum-Yanwei", "name": { "family": "Lum", "given": "Yanwei" } }, { "id": "Cheng-Mu\u2010Jeng", "name": { "family": "Cheng", "given": "Mu\u2010Jeng" } }, { "id": "Kim-Kwang-Ho", "name": { "family": "Kim", "given": "Kwang Ho" } }, { "id": "Head\u2010Gordon-M", "name": { "family": "Head\u2010Gordon", "given": "Martin" } }, { "id": "Kang-Jeung-Ku", "name": { "family": "Kang", "given": "Jeung Ku" }, "orcid": "0000-0003-3409-7544" } ] }, "title": "Atomic-Scale Spacing between Copper Facets for the Electrochemical Reduction of Carbon Dioxide", "ispublished": "pub", "full_text_status": "public", "keywords": "3D tomography; Cu nanoparticles; C2+ fuels; CO2 reduction, C\u2013C coupling reactions", "note": "\u00a9 2020 Wiley\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: October 18, 2019; Revised: December 5, 2019; Published online: 30 January 2020. \n\nH.M.J. and Y.K. contributed equally to this work. This work was mainly supported by the Global Frontier R&D Program on Center for Hybrid Interface Materials, the Korea Center for Artificial Photosynthesis (2009\u20100093881), and the National Research Foundation of Korea (2017M2A2A6A01070673, 2018R1C1B6004358 and 2019M3E6A1104196) funded by the Ministry of Science and ICT, Republic of Korea. In addition, Y.K. was supported by the Next Generation Carbon Upcycling project (2017M1A2A2043122) through the National Research Foundation funded by the Ministry of Science and ICT, Republic of Korea. M.J.C. acknowledges financial support from the Ministry of Science and Technology of the Republic of China under MOST 107\u20102113\u2010M\u2010006\u2010008\u2010MY2. Product analysis for electrochemical CO\u2082 reduction was carried out at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award number DE\u2010SC0004993. \n\nThe authors thank Mr. Hyung\u2010bin Bae at KAIST analysis center for research advancement (KARA) for technical assistance in TEM analysis. \n\nThe authors declare no conflict of interest.\n\nSupplemental Material - aenm201903423-sup-0001-suppmat.pdf
", "abstract": "Copper (Cu) offers a means for producing value\u2010added fuels through the electrochemical reduction of carbon dioxide (CO\u2082), i.e., the CO\u2082 reduction reaction (CO\u2082RR), but designing Cu catalysts with significant Faradaic efficiency to C\u2082\u208a products remains as a great challenge. This work demonstrates that the high activity and selectivity of Cu to C\u2082\u208a products can be achieved by atomic\u2010scale spacings between two facets of Cu particles. These spacings are created by lithiating CuO_x particles, removing lithium oxides formed, and electrochemically reducing CuO_x to metallic Cu. Also, the range of spacing (d_s) is confirmed via the 3D tomographs using the Cs\u2010corrected scanning transmission electron microscopy (3D tomo\u2010STEM), and the operando X\u2010ray absorption spectra show that oxidized Cu reduces to the metallic state during the CO\u2082RR. Moreover, control of d_s to 5\u20136 \u00c5 allows a current density exceeding that of unmodified CuO_x nanoparticles by about 12 folds and a Faradaic efficiency of \u224880% to C\u2082\u208a. Density functional theory calculations support that d_s of 5\u20136 \u00c5 maximizes the binding energies of CO\u2082 reduction intermediates and promotes C\u2013C coupling reactions. Consequently, this study suggests that control of d_s can be used to realize the high activity and C\u2082\u208a product selectivity for the CO\u2082RR.", "date": "2020-03-10", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "10", "number": "10", "publisher": "Wiley", "pagerange": "Art. No. 1903423", "id_number": "CaltechAUTHORS:20200206-111205774", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200206-111205774", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Korea Center for Artificial Photosynthesis", "grant_number": "2009\u20100093881" }, { "agency": "National Research Foundation of Korea", "grant_number": "2017M2A2A6A01070673" }, { "agency": "National Research Foundation of Korea", "grant_number": "2018R1C1B6004358" }, { "agency": "National Research Foundation of Korea", "grant_number": "2019M3E6A1104196" }, { "agency": "Ministry of Science and ICT (Korea)" }, { "agency": "National Research Foundation of Korea", "grant_number": "2017M1A2A2043122" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 107\u20102113\u2010M\u2010006\u2010008\u2010MY2" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201903423", "primary_object": { "basename": "aenm201903423-sup-0001-suppmat.pdf", "url": "https://authors.library.caltech.edu/records/0hch1-hpn96/files/aenm201903423-sup-0001-suppmat.pdf" }, "pub_year": "2020", "author_list": "Jeong, Hyung Mo; Kwon, Youngkook; et el." }, { "id": "https://authors.library.caltech.edu/records/pp53y-mvb03", "eprint_id": 100371, "eprint_status": "archive", "datestamp": "2023-08-19 20:25:38", "lastmod": "2023-10-18 19:54:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spitler-Mark-T", "name": { "family": "Spitler", "given": "Mark T." }, "orcid": "0000-0003-4153-989X" }, { "id": "Modestino-Miguel-A", "name": { "family": "Modestino", "given": "Miguel A." }, "orcid": "0000-0003-2100-7335" }, { "id": "Deutsch-Todd-G", "name": { "family": "Deutsch", "given": "Todd G." }, "orcid": "0000-0001-6577-1226" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang X." }, "orcid": "0000-0002-1698-6754" }, { "id": "Durrant-James-R", "name": { "family": "Durrant", "given": "James R." }, "orcid": "0000-0001-8353-7345" }, { "id": "Esposito-Daniel-V", "name": { "family": "Esposito", "given": "Daniel V." }, "orcid": "0000-0002-0550-801X" }, { "id": "Haussener-Sophia", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Maldonado-Stephen", "name": { "family": "Maldonado", "given": "Stephen" }, "orcid": "0000-0002-2917-4851" }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Parkinson-Bruce-Alan", "name": { "family": "Parkinson", "given": "Bruce A." }, "orcid": "0000-0002-8950-1922" }, { "id": "Ginlet-David-S", "name": { "family": "Ginley", "given": "David S." } }, { "id": "Houle-Frances-A", "name": { "family": "Houle", "given": "Frances A." }, "orcid": "0000-0001-5571-2548" }, { "id": "Hannappel-Thomas", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" }, { "id": "Neale-Nathan-R", "name": { "family": "Neale", "given": "Nathan R." }, "orcid": "0000-0001-5654-1664" }, { "id": "Nocera-Daniel-G", "name": { "family": "Nocera", "given": "Daniel G." }, "orcid": "0000-0001-5055-320X" }, { "id": "McIntyre-Paul-C", "name": { "family": "McIntyre", "given": "Paul C." } } ] }, "title": "Practical challenges in the development of photoelectrochemical solar fuels production", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2020. \n\nThe article was received on 27 Sep 2019, accepted on 24 Nov 2019 and first published on 04 Dec 2019. \n\nThis perspective derives from a Workshop on the \"Practical Challenges in the Development of Photoelectrochemical Solar Fuels Production\" held on August 13, 2018 in conjunction with the Gerischer Electrochemistry Today Symposium in Boulder, Colorado, August 14\u201316, 2018. The authors acknowledge the generous support of this workshop by the Renewable and Sustainable Energy Institute (RASEI) at CU Boulder and the National Renewable Energy Laboratory (NREL). \n\nAll authors contributed equally to this work, with the sequence of the authors reflecting the order of their contribution in the text. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c9se00869a1_si.pdf
", "abstract": "This article addresses the challenges presented by photoelectrochemical solar fuels technology in a discussion that begins with a functioning device and proceeds to the more fundamental science of its component parts. In this flow of discussion issues are addressed that frame the discussion for the next, increasingly more fundamental topic. The analysis begins with a discussion of the need for an analytical facility for confirmation of reported efficiencies of solar fuels device prototypes and then progressively narrows its scope to prototype design, the discovery of novel materials and the design of durable interfacial structures for fuels evolution. Molecular hydrogen will be considered first as the target fuel since many of the challenges with hydrogen production are general and applicable to the more complex CO\u2082 reduction, which will be treated as a supplementary subject.", "date": "2020-03-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "4", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "985-995", "id_number": "CaltechAUTHORS:20191219-112734154", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191219-112734154", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Renewable Energy Laboratory" }, { "agency": "University of Colorado" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9se00869a", "primary_object": { "basename": "c9se00869a1_si.pdf", "url": "https://authors.library.caltech.edu/records/pp53y-mvb03/files/c9se00869a1_si.pdf" }, "pub_year": "2020", "author_list": "Spitler, Mark T.; Modestino, Miguel A.; et el." }, { "id": "https://authors.library.caltech.edu/records/p5691-g7h46", "eprint_id": 101650, "eprint_status": "archive", "datestamp": "2023-08-22 04:12:36", "lastmod": "2023-10-19 22:55:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nam-Dae-Hyun", "name": { "family": "Nam", "given": "Dae-Hyun" }, "orcid": "0000-0002-0871-1355" }, { "id": "De-Luna-Phil", "name": { "family": "De Luna", "given": "Phil" }, "orcid": "0000-0002-7729-8816" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Li-Fengwang", "name": { "family": "Li", "given": "Fengwang" }, "orcid": "0000-0003-1531-2966" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Shekhah-Osama", "name": { "family": "Shekhah", "given": "Osama" }, "orcid": "0000-0003-1861-9226" }, { "id": "Eddaoudi-Mohamed", "name": { "family": "Eddaoudi", "given": "Mohamed" }, "orcid": "0000-0003-1916-9837" }, { "id": "Sargent-Edward-H", "name": { "family": "Sargent", "given": "Edward H." }, "orcid": "0000-0003-0396-6495" } ] }, "title": "Molecular enhancement of heterogeneous CO\u2082 reduction", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Engineering; Materials science", "note": "\u00a9 2020 Springer Nature Limited. \n\nReceived 16 January 2019; Accepted 08 January 2020; Published 25 February 2020. \n\nThis work was in part supported financially by the Natural Sciences and Engineering Research Council of Canada, the Ontario Research Fund: Research Excellence Program (ORF-RE-RE08-034), the Natural Resources Canada Clean Growth Program (CGP-17-0455) and CIFAR Bio-Inspired Solar Energy Program (FL-000719). This work was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy InnovationHub, supported through the Office of Science of the US Department of Energy under award no. DESC0004993, and was also based on work supported by the King Abdullah University of Science and Technology (KAUST) Office of Sponsored Research (OSR) under award no. OSR-2018-CPF-3665-03 and OSR-2019-CCF-1972.04. P.D.L. acknowledges the Natural Sciences and Engineering Research Council of Canada for support in the form of a Canada Graduate Scholarship and A.T. acknowledges the European Union's Horizon 2020 research and innovation programme under the Marie Sk\u0142odowska-Curie Action H2020-MSCA-IF-2017 (793471). \n\nThese authors contributed equally: Dae-Hyun Nam, Phil De Luna. \n\nThe authors declare no competing interests.", "abstract": "The electrocatalytic carbon dioxide reduction reaction (CO\u2082RR) addresses the need for storage of renewable energy in valuable carbon-based fuels and feedstocks, yet challenges remain in the improvement of electrosynthesis pathways for highly selective hydrocarbon production. To improve catalysis further, it is of increasing interest to lever synergies between heterogeneous and homogeneous approaches. Organic molecules or metal complexes adjacent to heterogeneous active sites provide additional binding interactions that may tune the stability of intermediates, improving catalytic performance by increasing Faradaic efficiency (product selectivity), as well as decreasing overpotential. We offer a forward-looking perspective on molecularly enhanced heterogeneous catalysis for CO\u2082RR. We discuss four categories of molecularly enhanced strategies: molecular-additive-modified heterogeneous catalysts, immobilized organometallic complex catalysts, reticular catalysts and metal-free polymer catalysts. We introduce present-day challenges in molecular strategies and describe a vision for CO2RR electrocatalysis towards multi-carbon products. These strategies provide potential avenues to address the challenges of catalyst activity, selectivity and stability in the further development of CO\u2082RR.", "date": "2020-03", "date_type": "published", "publication": "Nature Materials", "volume": "19", "number": "3", "publisher": "Nature Publishing Group", "pagerange": "266-276", "id_number": "CaltechAUTHORS:20200302-110558568", "issn": "1476-1122", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200302-110558568", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Ontario Research Fund", "grant_number": "ORF-RE-RE08-034" }, { "agency": "Natural Resources Canada", "grant_number": "CGP-17-0455" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)", "grant_number": "FL-000719" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DESC0004993" }, { "agency": "King Abdullah University of Science and Technology (KAUST)", "grant_number": "OSR-2018-CPF-3665-03" }, { "agency": "King Abdullah University of Science and Technology (KAUST)", "grant_number": "OSR-2019-CCF-1972.04" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41563-020-0610-2", "pub_year": "2020", "author_list": "Nam, Dae-Hyun; De Luna, Phil; et el." }, { "id": "https://authors.library.caltech.edu/records/45w8y-nh516", "eprint_id": 100639, "eprint_status": "archive", "datestamp": "2023-08-22 04:06:25", "lastmod": "2023-10-23 16:14:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-Aniketa", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Persson-Kristin-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combinatorial screening yields discovery of 29 metal oxide photoanodes for solar fuel generation", "ispublished": "pub", "full_text_status": "public", "keywords": "solar fuels; photoanode; metal oxide", "note": "\u00a9 2020 The Royal Society of Chemistry. \n\nReceived 18th December 2019, Accepted 29th January 2020, First published on 31st January 2020. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. There are no conflicts to declare.\n\nSubmitted - photoanodes_2019disc_submit1_chemrxiv.pdf
Supplemental Material - c9ta13829c1_si.pdf
", "abstract": "Combinatorial synthesis combined with high throughput electrochemistry enabled discovery of 29 ternary oxide photoanodes, 15 with visible light response for oxygen evolution. Y\u2083Fe\u2085O\u2081\u2082 and trigonal V\u2082CoO\u2086 emerge as particularly promising candidates due to their photorepsonse at sub-2.4 eV illumination.", "date": "2020-02-28", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "8", "number": "8", "publisher": "Royal Society of Chemistry", "pagerange": "4239-4243", "id_number": "CaltechAUTHORS:20200110-145307662", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200110-145307662", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9ta13829c", "primary_object": { "basename": "c9ta13829c1_si.pdf", "url": "https://authors.library.caltech.edu/records/45w8y-nh516/files/c9ta13829c1_si.pdf" }, "related_objects": [ { "basename": "photoanodes_2019disc_submit1_chemrxiv.pdf", "url": "https://authors.library.caltech.edu/records/45w8y-nh516/files/photoanodes_2019disc_submit1_chemrxiv.pdf" } ], "pub_year": "2020", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/qy9xr-bw259", "eprint_id": 100605, "eprint_status": "archive", "datestamp": "2023-08-19 19:58:21", "lastmod": "2023-10-18 21:39:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Larson-David-M", "name": { "family": "Larson", "given": "David M." } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "CO\u2082 Reduction to CO with 19% Efficiency in a Solar-Driven Gas Diffusion Electrode Flow Cell under Outdoor Solar Illumination", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: November 26, 2019; Accepted: January 8, 2020; Published: January 9, 2020. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. \n\nAuthor Contributions: W.H.C., M.H.R., and H.A.A. conceived of the experimental study. W.H.C. and M.H.R. executed the experiments and did the data analysis. D.M.L., I.S., B.S.B., and C.X. provided technical support and scientific discussion. W.H.C., M.H.R., B.S.B., and H.A.A. wrote the paper and all authors commented on the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz9b02576_si_001.pdf
", "abstract": "Solar-driven reduction of carbon dioxide represents a carbon-neutral pathway for the synthesis of fuels and chemicals. We report here results for solar-driven CO\u2082 reduction using a gas diffusion electrode (GDE) directly powered by a photovoltaic cell. A GaInP/GaInAs/Ge triple-junction photovoltaic cell was used to power a reverse-assembled gas diffusion electrode employing a Ag nanoparticle catalyst layer. The device had a solar-to-CO energy conversion efficiency of 19.1% under simulated AM 1.5G illumination at 1 Sun. The use of a reverse-assembled GDE prevented transition from a wetted to a flooded catalyst bed and allowed the device to operate stably for >150 h with no loss in efficiency. Outdoor measurements were performed under ambient solar illumination in Pasadena, California, resulting in a peak solar-to-CO efficiency of 18.7% with a CO production rate of 47 mg\u00b7cm\u207b\u00b2 per day and a diurnal-averaged solar-to-fuel conversion efficiency of 5.8%.", "date": "2020-02-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "5", "number": "2", "publisher": "American Chemical Society", "pagerange": "470-476", "id_number": "CaltechAUTHORS:20200109-143243316", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200109-143243316", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.9b02576", "primary_object": { "basename": "nz9b02576_si_001.pdf", "url": "https://authors.library.caltech.edu/records/qy9xr-bw259/files/nz9b02576_si_001.pdf" }, "pub_year": "2020", "author_list": "Cheng, Wen-Hui; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/gtwtk-8pm63", "eprint_id": 100673, "eprint_status": "archive", "datestamp": "2023-08-19 19:53:12", "lastmod": "2023-10-18 21:44:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ge-Lei", "name": { "family": "Ge", "given": "Lei" } }, { "id": "Yuan-Hao", "name": { "family": "Yuan", "given": "Hao" }, "orcid": "0000-0003-3323-2855" }, { "id": "Min-Yuxiang", "name": { "family": "Min", "given": "Yuxiang" } }, { "id": "Li-Li", "name": { "family": "Li", "given": "Li" }, "orcid": "0000-0001-9260-823X" }, { "id": "Chen-Shiqian", "name": { "family": "Chen", "given": "Shiqian" } }, { "id": "Xu-Lai", "name": { "family": "Xu", "given": "Lai" }, "orcid": "0000-0003-2473-3359" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Predicted Optimal Bifunctional Electrocatalysts for the Hydrogen Evolution Reaction and the Oxygen Evolution Reaction Using Chalcogenide Heterostructures Based on Machine Learning Analysis of in Silico Quantum Mechanics Based High Throughput Screening", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2020 American Chemical Society. \n\nReceived: December 29, 2019; Accepted: January 11, 2020; Published: January 11, 2020. \n\nWe acknowledge financial support from National Key R&D Program of China (Grant No. 2017YFB0701600), the National Natural Science Foundation of China (Grant No. 91961120), Caltech-Soochow Multiscale nanoMaterials Genome Center (MnG), Innovative and Entrepreneurial Doctor (World-Famous Universities) in Jiangsu Province, Talent in Demand in the city of Suzhou. This project is also funded by the Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), the 111 Project, and Joint International Research Laboratory of Carbon-Based Functional Materials and Devices. The Caltech studies were supported by the US NSF (CBET-1805022) and the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz9b03875_si_001.pdf
", "abstract": "Two-dimensional van der Waals heterostructure materials, particularly transition metal dichalcogenides (TMDC), have proved to be excellent photoabsorbers for solar radiation, but performance for such electrocatalysis processes as water splitting to form H\u2082 and O\u2082 is not adequate. We propose that dramatically improved performance may be achieved by combining two independent TMDC while optimizing such descriptors as rotational angle, bond length, distance between layers, and the ratio of the bandgaps of two component materials. In this paper we apply the least absolute shrinkage and selection operator (LASSO) process of artificial intelligence incorporating these descriptors together with quantum mechanics (density functional theory) to predict novel structures with predicted superior performance. Our predicted best system is MoTe\u2082/WTe\u2082 with a rotation of 300\u00b0, which is predicted to have an overpotential of 0.03 V for HER and 0.17 V for OER, dramatically improved over current electrocatalysts for water splitting.", "date": "2020-02-06", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "11", "number": "3", "publisher": "American Chemical Society", "pagerange": "869-876", "id_number": "CaltechAUTHORS:20200113-103102011", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20200113-103102011", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFB0701600" }, { "agency": "National Natural Science Foundation of China", "grant_number": "91961120" }, { "agency": "Caltech-Soochow Multiscale nanoMaterials Genome Center (MnG)" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Jiangsu Higher Education Institutions" }, { "agency": "111 Project of China" }, { "agency": "Joint International Research Laboratory of Carbon-Based Functional Materials and Devices" }, { "agency": "NSF", "grant_number": "CBET-1805022" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1364", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.9b03875", "primary_object": { "basename": "jz9b03875_si_001.pdf", "url": "https://authors.library.caltech.edu/records/gtwtk-8pm63/files/jz9b03875_si_001.pdf" }, "pub_year": "2020", "author_list": "Ge, Lei; Yuan, Hao; et el." }, { "id": "https://authors.library.caltech.edu/records/1bywh-85964", "eprint_id": 98698, "eprint_status": "archive", "datestamp": "2023-08-22 03:41:03", "lastmod": "2023-10-18 17:34:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Fengwang", "name": { "family": "Li", "given": "Fengwang" }, "orcid": "0000-0003-1531-2966" }, { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Han-Zhiji", "name": { "family": "Han", "given": "Zhiji" }, "orcid": "0000-0001-9349-1571" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Molecular tuning of CO\u2082-to-ethylene conversion", "ispublished": "pub", "full_text_status": "public", "keywords": "Catalysis; Renewable energy", "note": "\u00a9 2019 Springer Nature Limited. \n\nReceived 21 December 2018; Accepted 01 October 2019; Published 20 November 2019. \n\nThis work was financially supported by the Ontario Research Fund:\nResearch Excellence Program, the Natural Sciences and Engineering Research Council (NSERC) of Canada, the CIFAR Bio-Inspired Solar Energy program, and the Joint Centre of Artificial Synthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. All DFT computations were performed on the IBM BlueGene/Q supercomputer with support from the Southern Ontario Smart Computing Innovation Platform (SOSCIP). SOSCIP is funded by the Federal Economic Development Agency of Southern Ontario, the Province of Ontario, IBM Canada Ltd., Ontario Centres of Excellence, Mitacs and 15 Ontario academic member institutions. This research was enabled in part by support provided by Compute Ontario (www.computeontario.ca) and Compute Canada (www.computecanada.ca). This research used synchrotron resources of the Advanced Photon Source (APS), an Office of Science User Facility operated for the U.S. Department of Energy (DOE) Office of Science by Argonne National Laboratory, and was\nsupported by the U.S. DOE under Contract No. DE-AC02-06CH11357, and the Canadian Light Source and its funding partners. We thank T. Wu and L. Ma for technical support at 9BM beamline of APS. D.S. acknowledges the NSERC E.W.R Steacie Memorial Fellowship. A.T. acknowledges Marie Sk\u0142odowska-Curie Fellowship H2020-MSCA-IF-2017 (793471). J.L. acknowledges the Banting postdoctoral fellowship. C.M.G. acknowledges NSERC for funding in\nthe form of a postdoctoral fellowship from the government of Canada. J.P.E. thanks NSERC, Hatch and the Government of Ontario for their support through graduate scholarships. \n\nAuthor contributions: E.H.S., T.A. and J.C.P. supervised this project. F.L. and Y.L. carried out electrochemical experiments. A.T. and A.R.H. carried out molecule synthesis and characterizations. Z.W. carried out DFT calculations. C.M.G. and F.L. conducted in situ Raman measurement. F.L. and A.O. carried out the membrane-electrode-assembly experiments. J. L. and F.L. performed X-ray spectroscopy measurements. Y.W. carried out SEM and EIS measurements. J.P.E. measured the contact angle. C.M. carried out the Comsol modelling. L.T. carried out EPR measurement under the supervision of R.D.B.. M.L. performed part of electrochemical experiments. Z. Q. L., X.W. and H.L. provided help in NMR analysis. C.M.G., C.P.O. and Y.X. provided help in membrane-electrode-assembly measurements. C.S.T. carried out AFM measurement. D.H.N. conducted XRD measurement. R.Q.B. carried out XPS measurement. C.T.D., T.Z, Y.C.L. and Z.H. provided help in materials synthesis and characterizations. F.L. and E.H.S. wrote the manuscript. All authors discussed the results and assisted during manuscript preparation. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41586_2019_1782_MOESM1_ESM.pdf
", "abstract": "The electrocatalytic carbon dioxide (CO\u2082) reduction reaction (CO\u2082RR) to value-added fuels and feedstocks provides a sustainable and carbon-neutral approach to the storage of intermittent renewable electricity. The highly selective generation of economically desirable C\u2082 products such as ethylene from CO\u2082RR remains a challenge. Tuning the stabilities of intermediates to favour a desired reaction pathway offers the opportunity to enhance selectivity, and this has recently been explored on copper (Cu) via control over morphology, grain boundaries7, facets, oxidation state and dopants. Unfortunately, the Faradaic efficiency for ethylene is still low in neutral media (60 per cent at a partial current density of 7 mA cm\u207b\u00b2 in the best catalyst reported so far), resulting in a low energy efficiency. Here we present a molecular tuning strategy\u2014the functionalization of the surface of electrocatalysts with organic molecules\u2014that stabilizes intermediates for enhanced CO\u2082RR to ethylene. Using electrochemical, operando/in situ spectroscopic and computational studies, we investigate the influence of a library of molecules, derived via electro-dimerization of arylpyridiniums, on Cu. We find that the adhered molecules improve the stabilization of an atop-bound CO intermediate, thereby favouring further reduction to ethylene. As a result of this strategy, we report the CO\u2082RR to ethylene with a Faradaic efficiency of 72 per cent at a partial current density of 230 mA cm\u207b\u00b2 in a liquid-electrolyte flow cell in neutral medium. We report stable ethylene electrosynthesis for 190 hours in a membrane-electrode-assembly-based system that provides a full-cell energy efficiency of 20 per cent. These findings indicate how molecular strategies can complement heterogeneous catalysts by stabilizing intermediates via local molecular tuning.", "date": "2020-01-23", "date_type": "published", "publication": "Nature", "volume": "577", "number": "7791", "publisher": "Nature Publishing Group", "pagerange": "509-513", "id_number": "CaltechAUTHORS:20190917-154117893", "issn": "0028-0836", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-154117893", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ontario Research Fund-Research Excellence" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canadian Institute for Advanced Research (CIFAR)" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Federal Economic Development Agency of Southern Ontario" }, { "agency": "Province of Ontario" }, { "agency": "IBM Canada Ltd." }, { "agency": "MITACS" }, { "agency": "Compute Ontario" }, { "agency": "Compute Canada" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-06CH11357" }, { "agency": "Canadian Light Source" }, { "agency": "Marie Curie Fellowship", "grant_number": "H2020-MSCA-IF-2017" }, { "agency": "Marie Curie Fellowship", "grant_number": "793471" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41586-019-1782-2", "primary_object": { "basename": "41586_2019_1782_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/1bywh-85964/files/41586_2019_1782_MOESM1_ESM.pdf" }, "pub_year": "2020", "author_list": "Li, Fengwang; Thevenon, Arnaud; et el." }, { "id": "https://authors.library.caltech.edu/records/c16ff-ejs04", "eprint_id": 100139, "eprint_status": "archive", "datestamp": "2023-08-22 03:38:41", "lastmod": "2023-10-18 19:07:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "Chu F." } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald C." }, "orcid": "0000-0002-0306-5462" }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." }, "orcid": "0000-0003-2467-6630" } ] }, "title": "Selective conversion of CO into ethanol on Cu(511) surface reconstructed from Cu(pc): Operando studies by electrochemical scanning tunneling microscopy, mass spectrometry, quartz crystal nanobalance, and infrared spectroscopy", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electrochemically generated Cu(511) surface; Operando electrode-surface microscopy; Operando molecular vibrational spectroscopy; CO adsorption on Cu vicinal surface; Selective reduction of CO into ethanol", "note": "\u00a9 2019 Published by Elsevier B.V. \n\nReceived 30 September 2019, Revised 20 November 2019, Accepted 26 November 2019, Available online 28 November 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.\n\nAuthors contributions: J.H.B., Y.-G.K., C.F.T., A.C.J., K.D.C. and J.C.H. designed research. J.H.B., Y.-G.K., C.F.T., A.C.J., performed research. J.H.B., Y.-G.K., C.F.T., A.C.J., K.D.C. and J.C.H. analyzed data. J.H.B. wrote the paper. \n\nDeclaration of interest: None.", "abstract": "A polycrystalline copper, surface-terminated by a well-defined (511)-oriented facet, was electrochemically generated by a series of step-wise surface reconstruction and iterations of mild oxidative-reductive processes in 0.1 M KOH. The electrochemical reduction of CO on the resultant stepped surface was investigated by four surface-sensitive operando methodologies: electrochemical scanning tunneling microscopy (STM), electrochemical quartz crystal nanobalance (EQCN), differential electrochemical mass spectrometry (DEMS), and polarization-modulation infrared spectroscopy (PMIRS). The stepped surface catalyzed the facile conversion of CO into ethanol, the exclusive alcohol product at a low overpotential of \u22121.06 V (SHE) or \u2212 0.3 V (RHE). The chemisorption of CO was found to be a necessary prelude to ethanol production; i.e. the surface coverages, rather than solution concentrations, of CO and its surface-bound intermediates primarily dictate the reaction rates (current densities). Contrary to the expected predominance of undercoordinated step-site reactivity over the coordination chemistry of vicinal surfaces, vibrational spectroscopic evidence reveals the involvement of terrace-bound CO adsorbates during the multi-atomic transformations associated with the production of ethanol.", "date": "2020-01-15", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "857", "publisher": "Elsevier", "pagerange": "Art. No. 113704", "id_number": "CaltechAUTHORS:20191202-112107473", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191202-112107473", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2019.113704", "pub_year": "2020", "author_list": "Baricuatro, Jack H.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/7pe2g-q5j41", "eprint_id": 100276, "eprint_status": "archive", "datestamp": "2023-08-19 19:31:28", "lastmod": "2023-10-18 19:48:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yalamanchili-Sisir", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Verlage-Erik", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Jahelka-Philip-R", "name": { "family": "Jahelka", "given": "Philip R." }, "orcid": "0000-0002-1460-7933" }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Saive-Rebecca", "name": { "family": "Saive", "given": "Rebecca" }, "orcid": "0000-0001-7420-9155" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "High Broadband Light Transmission for Solar Fuels Production Using Dielectric Optical Waveguides in TiO\u2082 Nanocone Arrays", "ispublished": "pub", "full_text_status": "public", "keywords": "dielectric nanocone, broadband transmission, nanophotonic, optoelectronic, photoelectrochemical, photovoltaic", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: October 12, 2019; Revised: November 29, 2019; Published: December 10, 2019. \n\nThe fabrication and assessment of photoanodes for the oxygen-evolution reaction was supported through the Office of Science of the U. S. Department of Energy under Award No. DE-SC0004993 for the Joint Center for Artificial Photosynthesis and used facilities of the Kavli Nanoscience Institute at Caltech, a DOE Energy Innovation Hub; the development of simulations was supported by the National Science Foundation under award No. EEC-1041895. \n\nAuthor Contributions: S.Y., E.V., and W.H.C. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nl9b04225_si_001.pdf
", "abstract": "We describe the fabrication and use of arrays of TiO\u2082 nanocones to yield high optical transmission into semiconductor photoelectrodes covered with high surface loadings of light-absorbing electrocatalysts. Covering over 50% of the surface of a light absorber with an array of high-refractive-index TiO\u2082 nanocones imparted antireflective behavior (< 5% reflectance) to the surface and allowed > 85% transmission of broadband light to the underlying Si, even when thick metal contacts or opaque catalyst coatings were deposited on areas of the light-facing surface that were not directly beneath a nanocone. Three-dimensional full-field electromagnetic simulations for the 400 \u2013 1100 nm spectral range showed that incident broadband illumination couples to multiple waveguide modes in the TiO\u2082 nanocones, reducing interactions of the light with the metal layer. A proof-of-concept experimental demonstration of light-driven water oxidation was performed using a p\u207an-Si photoanode decorated with an array of TiO\u2082 nanocones additionally having a Ni catalyst layer electrodeposited onto the areas of the p\u207an-Si surface left uncovered by the TiO\u2082 nanocones. This photoanode produced a light-limited photocurrent density of ~ 28 mA cm\u207b\u00b2 under 100 mW cm\u207b\u00b2 of simulated Air Mass 1.5 illumination, equivalent to the photocurrent density expected for a bare planar Si surface even though 54% of the front surface of the Si was covered by an ~ 70 nm thick Ni metal layer.", "date": "2020-01-08", "date_type": "published", "publication": "Nano Letters", "volume": "20", "number": "1", "publisher": "American Chemical Society", "pagerange": "502-508", "id_number": "CaltechAUTHORS:20191212-105210937", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191212-105210937", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "EEC-1041895" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.nanolett.9b04225", "primary_object": { "basename": "nl9b04225_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7pe2g-q5j41/files/nl9b04225_si_001.pdf" }, "pub_year": "2020", "author_list": "Yalamanchili, Sisir; Verlage, Erik; et el." }, { "id": "https://authors.library.caltech.edu/records/58whj-0gn64", "eprint_id": 100159, "eprint_status": "archive", "datestamp": "2023-08-19 19:28:31", "lastmod": "2023-10-18 19:08:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Fu-Harold-J", "name": { "family": "Fu", "given": "Harold J." }, "orcid": "0000-0001-9738-209X" }, { "id": "Ifkovits-Zachary-P", "name": { "family": "Ifkovits", "given": "Zachary P." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Spontaneous Formation of >90% Optically Transmissive, Electrochemically Active CoP Films for Photoelectrochemical Hydrogen Evolution", "ispublished": "pub", "full_text_status": "public", "keywords": "Photoelectrochemistry, Solar Fuels, Catalysts, Photocathode, Phosphides", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: October 3, 2019; Accepted: December 2, 2019; Published: December 2, 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. AFM measurements were performed in the Molecular Materials Resource Center, supported by the Beckmann Institute at the California Institute of Technology. We thank T. Tiwald for helpful discussions on models for effective medium approximations and N. Dalleska for assistance with ICP-MS. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz9b02926_si_001.pdf
", "abstract": "Earth-abundant catalysts for the hydrogen-evolution reaction require increased mass loadings, relative to Pt films, to achieve comparable activity and stability in acidic electrolytes. We report herein that spontaneous nanostructuring of opaque, electrodeposited CoP films, 40\u2013120 nm in thickness, leads to transparent electrocatalyst films that exhibit up to 90% optical transmission in the visible spectrum. The photocurrent density under simulated sunlight at a representative n+p-Si(100)/CoP photocathode increases by 200% after exposure to 0.50 M H\u2082SO\u2084 (aq) and remains stable for 12 h of continuous operation. Atomic force microscopy and scanning electron microscopy of the film before and after exposure to 0.50 M H\u2082SO\u2084 (aq) validate an optical model for transparent CoP films as probed with spectroscopic ellipsometry.", "date": "2020-01-02", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "11", "number": "1", "publisher": "American Chemical Society", "pagerange": "14-20", "id_number": "CaltechAUTHORS:20191203-081242656", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191203-081242656", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.9b02926", "primary_object": { "basename": "jz9b02926_si_001.pdf", "url": "https://authors.library.caltech.edu/records/58whj-0gn64/files/jz9b02926_si_001.pdf" }, "pub_year": "2020", "author_list": "Kempler, Paul A.; Fu, Harold J.; et el." }, { "id": "https://authors.library.caltech.edu/records/kx37j-r8949", "eprint_id": 99670, "eprint_status": "archive", "datestamp": "2023-08-22 03:21:39", "lastmod": "2023-10-23 17:01:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Jones-Ryan-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "The Sensitivity of Cu for Electrochemical Carbon Dioxide Reduction to Hydrocarbons as Revealed by High Throughput Experiments", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon Dioxide Reduction Electrocatalysts Electrochemical conversion; High Throughput Screening", "note": "\u00a9 2019 The Royal Society of Chemistry. \n\nThe article was received on 12 Sep 2019, accepted on 12 Nov 2019 and first published on 14 Nov 2019. \n\nConflicts of interest: There are no conflicts to declare.\n\nSubmitted - CuAlloy_submit1_chemrxiv.pdf
Supplemental Material - c9ta10111j1_si.pdf
", "abstract": "Electrochemical CO\u2082 reduction to valuable products is a centerpiece of future energy technologies that relies on identification of new catalysts. We present accelerated screening of Cu bimetallic alloys, revealing remarkable sensitivity to alloy concentration that indicates the migration of alloying elements to critical sites for hydrocarbon formation.", "date": "2019-12-21", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "7", "number": "47", "publisher": "Royal Society of Chemistry", "pagerange": "26785-26790", "id_number": "CaltechAUTHORS:20191105-102648597", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191105-102648597", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9ta10111j", "primary_object": { "basename": "CuAlloy_submit1_chemrxiv.pdf", "url": "https://authors.library.caltech.edu/records/kx37j-r8949/files/CuAlloy_submit1_chemrxiv.pdf" }, "related_objects": [ { "basename": "c9ta10111j1_si.pdf", "url": "https://authors.library.caltech.edu/records/kx37j-r8949/files/c9ta10111j1_si.pdf" } ], "pub_year": "2019", "author_list": "Lai, Yungchieh; Jones, Ryan J. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/nfcn9-2a530", "eprint_id": 95420, "eprint_status": "archive", "datestamp": "2023-08-19 19:12:48", "lastmod": "2023-10-20 20:13:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Went-C-M", "name": { "family": "Went", "given": "Cora M." } }, { "id": "Wong-Joeson", "name": { "family": "Wong", "given": "Joeson" }, "orcid": "0000-0002-6304-7602" }, { "id": "Jahelka-P-R", "name": { "family": "Jahelka", "given": "Phillip R." }, "orcid": "0000-0002-1460-7933" }, { "id": "Kelzenberg-M-D", "name": { "family": "Kelzenberg", "given": "Michael" }, "orcid": "0000-0002-6249-2827" }, { "id": "Biswas-S", "name": { "family": "Biswas", "given": "Souvik" } }, { "id": "Hunt-M-S", "name": { "family": "Hunt", "given": "Matthew S." } }, { "id": "Carbone-A", "name": { "family": "Carbone", "given": "Abigail" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "A new metal transfer process for van der Waals contacts to vertical Schottky-junction transition metal dichalcogenide photovoltaics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC).\nThis is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial license, which permits use, distribution, and reproduction in any medium, so long as the resultant use is not for commercial advantage and provided the original work is properly cited. \n\nSubmitted 8 April 2019; Accepted 30 October 2019; Published 20 December 2019. \n\nWe thank S. Nam for the useful discussions. \n\nThis work was supported by the DOE \"Photonics at Thermodynamic Limits\" Energy Frontier Research Center under grant DE-SC0019140. C.M.W. and J.W. acknowledge support from the NSF Graduate Research Fellowship under grants 1745301 and 1144469. C.M.W. acknowledges fellowship support from the Resnick Sustainability Institute. \n\nAuthor contributions: C.M.W. fabricated the devices, performed the measurements, and performed the simulations. C.M.W., J.W., P.R.J., and S.B. developed the metal transfer technique. J.W. and P.R.J. assisted with the simulations. M.K. assisted with the solar simulator, absorption, and EQE measurements. M.S.H. and A.C. assisted with the TEM sample preparation and imaging. H.A.A. supervised all the experiments, calculations, and data collection. All authors contributed to the data interpretation, presentation, and writing of the manuscript. \n\nThe authors declare that they have no competing interests. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.\n\nPublished - aax6061.pdf
Submitted - 1903.08191.pdf
Supplemental Material - aax6061_SM.pdf
", "abstract": "Two-dimensional transition metal dichalcogenides are promising candidates for ultrathin optoelectronic devices due to their high absorption coefficients and intrinsically passivated surfaces. To maintain these near-perfect surfaces, recent research has focused on fabricating contacts that limit Fermi-level pinning at the metal-semiconductor interface. Here, we develop a new, simple procedure for transferring metal contacts that does not require aligned lithography. Using this technique, we fabricate vertical Schottky-junction WS\u2082 solar cells, with Ag and Au as asymmetric work function contacts. Under laser illumination, we observe rectifying behavior and open-circuit voltage above 500 mV in devices with transferred contacts, in contrast to resistive behavior and open-circuit voltage below 15 mV in devices with evaporated contacts. One-sun measurements and device simulation results indicate that this metal transfer process could enable high specific power vertical Schottky-junction transition metal dichalcogenide photovoltaics, and we anticipate that this technique will lead to advances for two-dimensional devices more broadly.", "date": "2019-12-20", "date_type": "published", "publication": "Science Advances", "volume": "5", "number": "12", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eaax6061", "id_number": "CaltechAUTHORS:20190513-082509112", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190513-082509112", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019140" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1126/sciadv.aax6061", "pmcid": "PMC6924982", "primary_object": { "basename": "1903.08191.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/1903.08191.pdf" }, "related_objects": [ { "basename": "aax6061.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/aax6061.pdf" }, { "basename": "aax6061_SM.pdf", "url": "https://authors.library.caltech.edu/records/nfcn9-2a530/files/aax6061_SM.pdf" } ], "pub_year": "2019", "author_list": "Went, Cora M.; Wong, Joeson; et el." }, { "id": "https://authors.library.caltech.edu/records/61xah-ant14", "eprint_id": 109752, "eprint_status": "archive", "datestamp": "2023-08-19 19:05:27", "lastmod": "2023-10-23 15:49:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gauthier-Joseph-A", "name": { "family": "Gauthier", "given": "Joseph A." }, "orcid": "0000-0001-9542-0988" }, { "id": "Fields-Meredith", "name": { "family": "Fields", "given": "Meredith" } }, { "id": "Bajdich-Michal", "name": { "family": "Bajdich", "given": "Michal" }, "orcid": "0000-0003-1168-8616" }, { "id": "Chen-Leanne-D", "name": { "family": "Chen", "given": "Leanne D." }, "orcid": "0000-0001-9700-972X" }, { "id": "Sandberg-Robert-B", "name": { "family": "Sandberg", "given": "Robert B." } }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" }, { "id": "N\u00f8rskov-Jens-K", "name": { "family": "N\u00f8rskov", "given": "Jens K." }, "orcid": "0000-0002-4427-7728" } ] }, "title": "Facile Electron Transfer to CO\u2082 during Adsorption at the Metal | Solution Interface", "ispublished": "pub", "full_text_status": "public", "keywords": "Charge transfer, Electrical energy, Adsorption, Potential energy, Molecules", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: October 30, 2019; Published: November 12, 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work uses resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility, supported by the Office of Science of the U.S. DOE under Contract No. DE-AC02-05CH11231. M.F. also acknowledges the NSF for their graduate fellowship. K.C. and J.K.N. also acknowledge support from Research Grant 9455 from VILLUM FONDEN. \n\nThe authors declare no competing financial interest.\n\nSubmitted - facile-electron-transfer-to-co2-during-adsorption-at-the-metal-solution-interface_version2.pdf
Supplemental Material - jp9b10205_si_001.pdf
", "abstract": "We estimate the rate of electron transfer to CO\u2082 at the Au (211)|water interface during adsorption in an electrochemical environment under reducing potentials. On the basis of density functional theory calculations at the generalized gradient approximation and hybrid levels of theory, we find electron transfer to the adsorbed *CO\u2082 to be very facile. This high rate of transfer is estimated by the energy distribution of the adsorbate-induced density of states as well as from the interaction between diabatic states representing neutral and negatively charged CO\u2082. Up to 0.62 electrons is transferred to CO\u2082, and this charge adiabatically increases with the bending angle to a lower limit of 137\u00b0. We conclude that this rate of electron transfer is extremely fast compared to the time scale of the nuclear degrees of freedom, that is, the adsorption process.", "date": "2019-12-05", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "123", "number": "48", "publisher": "American Chemical Society", "pagerange": "29278-29283", "id_number": "CaltechAUTHORS:20210707-212629894", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20210707-212629894", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Villum Foundation", "grant_number": "9455" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.9b10205", "primary_object": { "basename": "facile-electron-transfer-to-co2-during-adsorption-at-the-metal-solution-interface_version2.pdf", "url": "https://authors.library.caltech.edu/records/61xah-ant14/files/facile-electron-transfer-to-co2-during-adsorption-at-the-metal-solution-interface_version2.pdf" }, "related_objects": [ { "basename": "jp9b10205_si_001.pdf", "url": "https://authors.library.caltech.edu/records/61xah-ant14/files/jp9b10205_si_001.pdf" } ], "pub_year": "2019", "author_list": "Gauthier, Joseph A.; Fields, Meredith; et el." }, { "id": "https://authors.library.caltech.edu/records/7a3j3-9c465", "eprint_id": 99476, "eprint_status": "archive", "datestamp": "2023-08-19 18:54:46", "lastmod": "2023-10-18 18:20:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Predicting Charge Transport in the Presence of Polarons: The Beyond-Quasiparticle Regime in SrTiO\u2083", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published by the American Physical Society. Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. \n\nReceived 26 August 2019; revised manuscript received 17 October 2019; published 2 December 2019. \n\nJ.-J.Z. has benefited from discussion with N.-E. Lee. This work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. M.B. acknowledges support by the National Science Foundation under Grant No. ACI-1642443, which provided for code development, and Grant No. CAREER-1750613, which provided for theory and method development. This work was partially supported by the Air Force Office of Scientific Research through the Young Investigator Program, Grant FA9550-18-1-0280. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevResearch.1.033138.pdf
Submitted - 1905.03414.pdf
", "abstract": "In materials with strong electron-phonon (e\u2212ph) interactions, the electrons carry a phonon cloud during their motion, forming quasiparticles known as polarons. Predicting charge transport and its temperature dependence in the polaron regime remains an open challenge. Here, we present first-principles calculations of charge transport in a prototypical material with large polarons, SrTiO\u2083. Using a cumulant diagram-resummation technique that can capture the strong e\u2212ph interactions, our calculations can accurately predict the experimental electron mobility in SrTiO\u2083 between 150\u2013300 K. They further reveal that for increasing temperature the charge transport mechanism transitions from bandlike conduction, in which the scattering of renormalized quasiparticles is dominant, to a beyond-quasiparticle transport regime governed by incoherent contributions due to the interactions between the electrons and their phonon cloud. Our work reveals long-sought microscopic details of charge transport in SrTiO\u2083, and provides a broadly applicable method for predicting charge transport in materials with strong e\u2212ph interactions and polarons.", "date": "2019-12", "date_type": "published", "publication": "Physical Review Research", "volume": "1", "number": "3", "publisher": "American Physical Society", "pagerange": "Art. No. 033138", "id_number": "CaltechAUTHORS:20191025-161728302", "issn": "2643-1564", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191025-161728302", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevResearch.1.033138", "primary_object": { "basename": "1905.03414.pdf", "url": "https://authors.library.caltech.edu/records/7a3j3-9c465/files/1905.03414.pdf" }, "related_objects": [ { "basename": "PhysRevResearch.1.033138.pdf", "url": "https://authors.library.caltech.edu/records/7a3j3-9c465/files/PhysRevResearch.1.033138.pdf" } ], "pub_year": "2019", "author_list": "Zhou, Jin-Jian and Bernardi, Marco" }, { "id": "https://authors.library.caltech.edu/records/hqzre-dpm46", "eprint_id": 99403, "eprint_status": "archive", "datestamp": "2023-08-19 18:46:22", "lastmod": "2023-10-18 18:16:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Noh-Juhwan", "name": { "family": "Noh", "given": "Juhwan" }, "orcid": "0000-0003-1183-9955" }, { "id": "Kim-Sungwon", "name": { "family": "Kim", "given": "Sungwon" } }, { "id": "Gu-Geun-ho", "name": { "family": "Gu", "given": "Geun ho" } }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Jung-Yousung", "name": { "family": "Jung", "given": "Yousung" }, "orcid": "0000-0003-2615-8394" } ] }, "title": "Unveiling new stable manganese based photoanode materials via theoretical high-throughput screening and experiments", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Royal Society of Chemistry. \n\nThe article was received on 30 Aug 2019, accepted on 14 Oct 2019 and first published on 14 Oct 2019. \n\nThe theoretical screening work was supported by the Korea Institute of Energy Technology Evaluation and Planning (KETEP-20188500000440) and National Research Foundation of Korea (NRF-2019M3E6A106470), and the experimental work was supported by the U.S. Department of Energy (DOE) under Award Number DE-SC0004993. We acknowledge the generous supercomputing time from KISTI. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c9cc06736a1_si.pdf
", "abstract": "With the increasing energy demand, developing renewable fuel production strategies such as photoelectrocatalytic hydrogen production is critical to mitigating the global climate change. In this work, we experimentally validate a new stable and photoactive material, Mg\u2082MnO\u2084, from the exhaustive theoretical exploration of the chemical space of X (=Mg and Ca), Mn and O.", "date": "2019-11-18", "date_type": "published", "publication": "Chemical Communications", "volume": "55", "number": "89", "publisher": "Royal Society of Chemistry", "pagerange": "13418-13421", "id_number": "CaltechAUTHORS:20191023-085621884", "issn": "1359-7345", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191023-085621884", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Korea Institute of Energy Technology Evaluation and Planning", "grant_number": "KETEP-20188500000440" }, { "agency": "National Research Foundation of Korea", "grant_number": "NRF-2019M3E6A106470" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9cc06736a", "primary_object": { "basename": "c9cc06736a1_si.pdf", "url": "https://authors.library.caltech.edu/records/hqzre-dpm46/files/c9cc06736a1_si.pdf" }, "pub_year": "2019", "author_list": "Noh, Juhwan; Kim, Sungwon; et el." }, { "id": "https://authors.library.caltech.edu/records/8gaqr-e8y86", "eprint_id": 98794, "eprint_status": "archive", "datestamp": "2023-08-22 03:01:05", "lastmod": "2023-10-18 17:38:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thevenon-Arnaud", "name": { "family": "Thevenon", "given": "Arnaud" }, "orcid": "0000-0002-5543-6595" }, { "id": "Rosas-Hern\u00e1ndez-Alonso", "name": { "family": "Rosas-Hern\u00e1ndez", "given": "Alonso" }, "orcid": "0000-0002-0812-5591" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "In-situ Nanostructuring and Stabilization of Polycrystalline Copper by an Organic Salt Additive Promotes Electrocatalytic CO\u2082 Reduction to Ethylene", "ispublished": "pub", "full_text_status": "public", "keywords": "Carbon Dioxide; electrocatalysis; ethylene; nanocubes; Stability", "note": "\u00a9 2019 Wiley-\u2010VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nAccepted manuscript online: 19 September 2019; Manuscript accepted: 19 September 2019; Manuscript revised: 13 August 2019; Manuscript received: 25 June 2019. \n\nNMR, AFM and XPS, SEM and EDX measurements were collected at the NMR Facility (Division of CCE), the Molecular Materials Research Center (Beckman Institute) and the Analytic Facilities (Division of Geological and Planetary Sciences) of the California Institute of Technology, respectively. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993 and Marie Curie Fellowship H2020-MSCA-IF-2017 (793471) (A.T.). J.C.P. acknowledges additional support from the Resnick Sustainability Institute at Caltech. \n\nThe authors declare no conflict of interest.\n\nSupplemental Material - anie201907935-s1-supportinginformation.pdf
", "abstract": "Bridging homogeneous molecular systems with heterogeneous catalysts is a promising approach for the development of new electrodes, combining the advantages of both approaches. In the context of CO\u2082 electroreduction, molecular enhancement of planar copper electrodes has enabled promising advancement towards high Faradaic efficiencies for multicarbon products. Besides, nanostructured copper electrodes have also demonstrated enhanced performance at comparatively low overpotentials. Herein, we report a novel and convenient method for nanostructuring copper electrodes using N,N'\u2010ethylene\u2010phenanthrolinium dibromide as molecular additive. Selectivities up to 70% for C\u2265\u2082 products are observed for more than 40 h without significant change in the surface morphology. Mechanistic studies reveal several roles for the organic additive, including: the formation of cube\u2010like nanostructures by corrosion of the copper surface, the stabilization of these nanostructures during electrocatalysis by formation of a protective organic layer, and the promotion of C\u2265\u2082 products.", "date": "2019-11-18", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "58", "number": "47", "publisher": "Wiley", "pagerange": "16952-16958", "id_number": "CaltechAUTHORS:20190923-102748967", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190923-102748967", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Marie Curie Fellowship", "grant_number": "H2020-MSCA-IF-2017" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1002/anie.201907935", "primary_object": { "basename": "anie201907935-s1-supportinginformation.pdf", "url": "https://authors.library.caltech.edu/records/8gaqr-e8y86/files/anie201907935-s1-supportinginformation.pdf" }, "pub_year": "2019", "author_list": "Thevenon, Arnaud; Rosas-Hern\u00e1ndez, Alonso; et el." }, { "id": "https://authors.library.caltech.edu/records/8ekv4-rp968", "eprint_id": 99304, "eprint_status": "archive", "datestamp": "2023-08-19 18:43:35", "lastmod": "2023-10-18 18:13:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Progress and prospects for accelerating materials science with automated and autonomous workflows", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. All publication charges for this article have been paid for by the Royal Society of Chemistry. \n\nThe article was received on 26 Jul 2019, accepted on 19 Sep 2019 and first published on 20 Sep 2019. \n\nThis material is based upon work supported by the Air Force Office of Scientific Research under award number FA9550-18-1-0136, the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993, and an Accelerated Materials Design and Discovery grant from the Toyota Research Institute.\n\nPublished - c9sc03766g.pdf
", "abstract": "Accelerating materials research by integrating automation with artificial intelligence is increasingly recognized as a grand scientific challenge to discover and develop materials for emerging and future technologies. While the solid state materials science community has demonstrated a broad range of high throughput methods and effectively leveraged computational techniques to accelerate individual research tasks, revolutionary acceleration of materials discovery has yet to be fully realized. This perspective review presents a framework and ontology to outline a materials experiment lifecycle and visualize materials discovery workflows, providing a context for mapping the realized levels of automation and the next generation of autonomous loops in terms of scientific and automation complexity. Expanding autonomous loops to encompass larger portions of complex workflows will require integration of a range of experimental techniques as well as automation of expert decisions, including subtle reasoning about data quality, responses to unexpected data, and model design. Recent demonstrations of workflows that integrate multiple techniques and include autonomous loops, combined with emerging advancements in artificial intelligence and high throughput experimentation, signal the imminence of a revolution in materials discovery.", "date": "2019-11-14", "date_type": "published", "publication": "Chemical Science", "volume": "10", "number": "42", "publisher": "Royal Society of Chemistry", "pagerange": "9640-9649", "id_number": "CaltechAUTHORS:20191016-131623439", "issn": "2041-6520", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191016-131623439", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Toyota Research Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c9sc03766g", "pmcid": "PMC7020936", "primary_object": { "basename": "c9sc03766g.pdf", "url": "https://authors.library.caltech.edu/records/8ekv4-rp968/files/c9sc03766g.pdf" }, "pub_year": "2019", "author_list": "Stein, Helge S. and Gregoire, John M." }, { "id": "https://authors.library.caltech.edu/records/rn6vt-czv02", "eprint_id": 99051, "eprint_status": "archive", "datestamp": "2023-08-19 18:41:40", "lastmod": "2023-10-18 17:48:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Hao", "name": { "family": "Yang", "given": "Hao" }, "orcid": "0000-0002-8241-6231" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Ren-Xiaoming", "name": { "family": "Ren", "given": "Xiaoming" } } ] }, "title": "Design of a One-Dimensional Stacked Spin Peierls System with Room-Temperature Switching from Quantum Mechanical Predictions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: July 30, 2019; Accepted: October 3, 2019; Published: October 3, 2019. \n\nWe thank the Joint Ph.D. program of China Scholarships Council (Grant CSC No. 201608320161) for financial support of H.Y. This work was partially supported by the Postdoctoral routine program from Office of Human Resources and Social Security in Jiangsu Province of China (Grant No. 2019Z282). We thank the National Nature Science Foundation of China (Grant Nos. 91122011, 21071080, and 21671100), Priority Academic Program Development of the Jiangsu Higher Education Institutions, and the 111 Project of Collaborative Innovation Center of Suzhou Nano Science & Technology; W.A.G. received support from the Department of Energy (DE-SC0014607). We used the computational resources from the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1548562. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz9b02219_si_001.pdf
", "abstract": "Planar bis-1,2-dithiolene complex anions of a transition metal (denoted as [M(dithiolato)\u2082]\u2212 and M = Ni, Pd, or Pt ion) favor forming columnar stacks of anions in the crystal that feature S = 1/2 spin-chains, and such a spin-chain compound often undergoes a spin-Peierls-type transition, making this a promising material for conducting and magnetic switching. However, current examples show the transition temperatures are far too low for most applications. We use quantum mechanics to predict that changing the cation arrangement from the boat-type to the chair-type packing configuration in a spin-Peierls-type [Ni(dithiolato)\u2082]\u207b complex will substantially stabilize the antiferromagnetic coupling, dramatically increasing the transition temperature. We estimate that the [Ni(mnt)\u2082]-based complexes (mnt = maleonitriledithiolate) with chair-type packing of cations will lead to critical temperatures of \u223c170, \u223c252, and \u223c310 K for S-, Se-, and Te-based mnt, respectively. We also suggest how to stabilize the chair-type configurations of these systems.", "date": "2019-11-07", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "10", "number": "21", "publisher": "American Chemical Society", "pagerange": "6432-6437", "id_number": "CaltechAUTHORS:20191003-113813931", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191003-113813931", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "China Scholarship Council", "grant_number": "201608320161" }, { "agency": "Jiangsu Office of Human Resources and Social Security", "grant_number": "2019Z282" }, { "agency": "National Natural Science Foundation of China", "grant_number": "91122011" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21071080" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21671100" }, { "agency": "Jiangsu Higher Education Institutions" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1354", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.9b02219", "primary_object": { "basename": "jz9b02219_si_001.pdf", "url": "https://authors.library.caltech.edu/records/rn6vt-czv02/files/jz9b02219_si_001.pdf" }, "pub_year": "2019", "author_list": "Yang, Hao; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/mzy8d-gv324", "eprint_id": 99012, "eprint_status": "archive", "datestamp": "2023-08-22 02:58:06", "lastmod": "2023-10-18 17:47:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Noh-Juhwan", "name": { "family": "Noh", "given": "Juhwan" }, "orcid": "0000-0003-1183-9955" }, { "id": "Kim-Jaehoon", "name": { "family": "Kim", "given": "Jaehoon" } }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Sanchez-Lengeling-B", "name": { "family": "Sanchez-Lengeling", "given": "Benjamin" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Aspuru-Guzik-A", "name": { "family": "Aspuru-Guzik", "given": "Al\u00e1n" } }, { "id": "Jung-Yousung", "name": { "family": "Jung", "given": "Yousung" }, "orcid": "0000-0003-2615-8394" } ] }, "title": "Inverse Design of Solid-State Materials via a Continuous Representation", "ispublished": "pub", "full_text_status": "public", "keywords": "MAP2: Benchmark; inverse design; generative model; machine learning; autoencoder; vanadium oxides; inorganic materials", "note": "\u00a9 2019 Elsevier. \n\nReceived 22 July 2019, Revised 6 August 2019, Accepted 17 August 2019, Available online 2 October 2019. \n\nWe acknowledge the support from the National Research Foundation of Korea (NRF-2017R1A2B3010176) and Korea Institute of Energy Technology Evaluation and Planning (KETEP-20188500000440) grants from the Korean Government, and a generous supercomputing time from Korea Insitute of Science and Technology Information (KISTI). H.S.S. and J.M.G. are supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. A.A.-G. thanks the Canada 150 Research Chairs Program, Natural Resources Canada, and the Vannevar Bush Faculty Fellowship Program for support. A.A.-G. acknowledges the generous support of Anders G. Fr\u00f8seth. \n\nAuthor Contributions: J.N., J.K., A.A.-G., and Y.J. designed the project. J.N. performed the machine-learning simulations, DFT calculations, and analyses. J.N. and Y.J. analyzed the results and wrote the manuscript. H.S.S. and J.M.G. assisted with data analysis and interpretation of the generated materials. B.S.-L. and A.A.-G. assisted with the machine-learning model construction. All authors contributed to the discussion and editing of the manuscript. Y.J. supervised the project. \n\nData and Code Availability: The datasets used to train the model and the generated crystal structures are available at https://github.com/kaist-amsg/imatgen.git. Source codes and trained parameters are available at https://github.com/kaist-amsg/imatgen.git. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 1-s2.0-S2590238519301754-mmc1.pdf
", "abstract": "The non-serendipitous discovery of materials with targeted properties is the ultimate goal of materials research, but to date, materials design lacks the incorporation of all available knowledge to plan the synthesis of the next material. This work presents a framework for learning a continuous representation of materials and building a model for new discovery using latent space representation. The ability of autoencoders to generate experimental materials is demonstrated with vanadium oxides via rediscovery of experimentally known structures when the model was trained without them. Approximately 20,000 hypothetical materials are generated, leading to several completely new metastable V_xO_y materials that may be synthesizable. Comparison with genetic algorithms suggests computational efficiency of generative models that can explore chemical compositional space effectively by learning the distributions of known materials for crystal structure prediction. These results are an important step toward machine-learned inverse design of inorganic functional materials using generative models.", "date": "2019-11-06", "date_type": "published", "publication": "Matter", "volume": "1", "number": "5", "publisher": "Elsevier", "pagerange": "1370-1384", "id_number": "CaltechAUTHORS:20191002-094950933", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191002-094950933", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea", "grant_number": "NRF-2017R1A2B3010176" }, { "agency": "Korea Institute of Energy Technology Evaluation and Planning", "grant_number": "20188500000440" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Canada Research Chairs Program" }, { "agency": "Natural Resources Canada" }, { "agency": "Vannevar Bush Fellowship" }, { "agency": "Anders G. Fr\u00f8seth" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2019.08.017", "primary_object": { "basename": "1-s2.0-S2590238519301754-mmc1.pdf", "url": "https://authors.library.caltech.edu/records/mzy8d-gv324/files/1-s2.0-S2590238519301754-mmc1.pdf" }, "pub_year": "2019", "author_list": "Noh, Juhwan; Kim, Jaehoon; et el." }, { "id": "https://authors.library.caltech.edu/records/rrwsx-4w245", "eprint_id": 99402, "eprint_status": "archive", "datestamp": "2023-08-19 18:21:05", "lastmod": "2023-10-18 18:16:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Oppenheim-Julius-J", "name": { "family": "Oppenheim", "given": "Julius J." }, "orcid": "0000-0002-5988-0677" }, { "id": "Yang-Hao", "name": { "family": "Yang", "given": "Hao" }, "orcid": "0000-0002-8241-6231" }, { "id": "Zhou-Tingting", "name": { "family": "Zhou", "given": "Tingting" }, "orcid": "0000-0003-3934-5770" }, { "id": "Zybin-Sergey-V", "name": { "family": "Zybin", "given": "Sergey" } }, { "id": "Rizk-Mohamed", "name": { "family": "Rizk", "given": "Mohamed" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Accurate non-bonded potentials based on periodic quantum mechanics calculations for use in molecular simulations of materials and systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published under license by AIP Publishing. \n\nSubmitted: 9 June 2019; Accepted: 24 September 2019; Published Online: 18 October 2019. \n\nS.N. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. W.A.G. was supported by the Computational Materials Sciences Program funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award Number DE-SC00014607. S.Z. was supported by the Office of Naval Research Grant Nos. N00014-19-1-2081 and N00014-18-1-2155. J.J.O. was supported by the Ernest H. Swift and Arthur A. Noyes SURF Fellowships. The calculations were carried out on the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the National Science Foundation, Grant No. ACI-1548562.\n\nPublished - 1.5113811.pdf
Accepted Version - JCP19-AR-02191.pdf
Supplemental Material - jcp19-ar-02191_sm.pdf
", "abstract": "Molecular dynamics simulations require accurate force fields (FFs) to describe the physical and chemical properties of complex materials and systems. FF parameters for valence interactions can be determined from high-quality Quantum Mechanical (QM) calculations. However, it has been challenging to extract long-range nonbonded interaction potentials from QM calculations since there is no unambiguous method to separate the total QM energy into electrostatics (polarization), van der Waals (vdW), and other components. Here, we propose to use density functional theory with dispersion corrections to obtain the equation of state for single element solid systems (of H, C, N, O, F, Cl, Br, I, P, He, Ne, Ar, Kr, Xe, and Rn) from which we obtain the pure 2-body vdW nonbonded potentials. Recently, we developed the polarizable charge equilibration (PQEq) model based on QM polarization energy of electric probe dipoles with no contributions from vdW. Together, the vdW and PQEq interactions form the nonbonded potential of our new transferrable reactive FF (RexPoN). They may also be useful to replace the nonbonded parts of standard FFs, such as OPLS, Amber, UFF, and CHARMM. We find that the individual 2-body vdW potential curves can be scaled to a universal vdW potential using just three specific atomic parameters. This simplifies extension to the rest of the periodic table for atoms that do not exhibit molecular packing. We validate the accuracy of these nonbonded interactions for liquid water, energetic, and biological systems. In all cases, we find that our new nonbonded potentials provide good agreement with QM and experimental data.", "date": "2019-10-21", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "151", "number": "15", "publisher": "American Institute of Physics", "pagerange": "Art. No. 154111", "id_number": "CaltechAUTHORS:20191023-085026382", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191023-085026382", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-19-1-2081" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-18-1-2155" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1357", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.5113811", "primary_object": { "basename": "1.5113811.pdf", "url": "https://authors.library.caltech.edu/records/rrwsx-4w245/files/1.5113811.pdf" }, "related_objects": [ { "basename": "JCP19-AR-02191.pdf", "url": "https://authors.library.caltech.edu/records/rrwsx-4w245/files/JCP19-AR-02191.pdf" }, { "basename": "jcp19-ar-02191_sm.pdf", "url": "https://authors.library.caltech.edu/records/rrwsx-4w245/files/jcp19-ar-02191_sm.pdf" } ], "pub_year": "2019", "author_list": "Naserifar, Saber; Oppenheim, Julius J.; et el." }, { "id": "https://authors.library.caltech.edu/records/nf85a-2ng35", "eprint_id": 98777, "eprint_status": "archive", "datestamp": "2023-08-19 18:20:56", "lastmod": "2023-10-18 17:38:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Lee-Soo-Hong", "name": { "family": "Lee", "given": "Soo Hong" }, "orcid": "0000-0002-2734-9654" }, { "id": "Lin-Meng", "name": { "family": "Lin", "given": "Meng" }, "orcid": "0000-0001-7785-749X" }, { "id": "Larson-D-M", "name": { "family": "Larson", "given": "David M." } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter S." }, "orcid": "0000-0002-8693-4562" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "A Hybrid Catalyst-Bonded Membrane Device for Electrochemical Carbon Monoxide Reduction at Different Relative Humidities", "ispublished": "pub", "full_text_status": "public", "keywords": "Gas Diffusion Electrode, Carbon Monoxide Reduction, Relative Humidity, Multiphysics modeling, Vapor-fed, operando X-ray Absorption Spectroscopy", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: August 22, 2019; Revised: September 19, 2019; Published: September 20, 2019. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. \n\nThe authors declare no competing financial interest.\n\nAccepted Version - acssuschemeng.9b04959.pdf
Supplemental Material - sc9b04959_si_001.pdf
", "abstract": "A hybrid catalyst-bonded membrane device using gaseous reactants for a carbon monoxide reduction (COR) reaction in the cathode chamber, an aqueous electrolyte for an oxygen evolution reaction (OER) in the anode chamber, and an anion exchange membrane (AEM) for product separation was modeled, constructed, and tested. The Cu electrocatalyst was electrodeposited onto gas diffusion layers (GDLs) and was directly bonded to AEM by mechanical pressing in the hybrid device. The impacts of relative humidity at the cathode inlet on the selectivity and activity of COR were investigated by computational modeling and experimental methods. At a relative humidity of 30%, the Cu-based catalyst in the hybrid device exhibited a total operating current density of 87 mA cm\u207b\u00b2 with a \u22122.0 V vs Ag/AgCl reference electrode, a Faradaic efficiency (FE) for C\u2082H\u2084 generation of 32.6%, and an FE for a liquid-based carbon product of 42.6%. Significant improvements in the partial current densities for COR were observed in relation to planar electrodes or flooded gas diffusion electrodes (GDEs). In addition, a custom test bed was constructed to characterize the oxidation states of the Cu catalysts in real time along with product analysis though the backside of the GDLs via operando X-ray absorption (XAS) measurements.", "date": "2019-10-21", "date_type": "published", "publication": "ACS Sustainable Chemistry & Engineering", "volume": "7", "number": "20", "publisher": "American Chemical Society", "pagerange": "16964-16970", "id_number": "CaltechAUTHORS:20190920-113304665", "issn": "2168-0485", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190920-113304665", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acssuschemeng.9b04959", "primary_object": { "basename": "acssuschemeng.9b04959.pdf", "url": "https://authors.library.caltech.edu/records/nf85a-2ng35/files/acssuschemeng.9b04959.pdf" }, "related_objects": [ { "basename": "sc9b04959_si_001.pdf", "url": "https://authors.library.caltech.edu/records/nf85a-2ng35/files/sc9b04959_si_001.pdf" } ], "pub_year": "2019", "author_list": "Sullivan, Ian; Han, Lihao; et el." }, { "id": "https://authors.library.caltech.edu/records/6e609-86h31", "eprint_id": 98914, "eprint_status": "archive", "datestamp": "2023-08-19 18:19:04", "lastmod": "2023-10-18 17:43:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-S", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Anomalies in Supercooled Water at ~230 K Arise from a 1D Polymer to 2D Network Topological Transformation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: August 20, 2019; Accepted: September 27, 2019; Published: September 27, 2019. \n\nWe thank the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993 for supporting S.N. and the Computational Materials Sciences Program funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award Number DE-SC00014607 for supporting W.A.G. The calculations were carried out on the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant Number ACI-1548562. \n\nAuthor Contributions: S.N. and W.A.G. designed the research; S.N. performed the research; S.N. and W.A.G. analyzed the data; and S.N. and W.A.G. wrote the paper. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz9b02443_si_001.pdf
", "abstract": "Puzzling anomalous properties of water are drastically enhanced in the supercooled region. However, the nature of these anomalies is not known. We report here molecular dynamics simulations using the RexPoN force field from 298 to 200 K along the 1 atm density curve. At 298 K, there are 2.1 strong hydrogen bonds (SHBs), leading to a dynamic branched one-dimensional (1D) polymer. Water remains 1D down to 240 K, but at and below 230 K, the number of SHBs becomes 3.0, leading to a two-dimensional (2D) network that persists to 200 K. We propose that this 1D-to-2D topological transition accounts for the anomalous properties of supercooled water. Near 230 K, the power spectra show dramatic increases in the angular vibrational frequency modes, while the diffusivity decreases dramatically, both arising from the 1D-to-2D transformation. This transition is not first order because free energy changes uniformly but fluctuations in the entropy near 230 K suggest a possible second-order transition.", "date": "2019-10-17", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "10", "number": "20", "publisher": "American Chemical Society", "pagerange": "6267-6273", "id_number": "CaltechAUTHORS:20190930-083231107", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190930-083231107", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1355", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.9b02443", "primary_object": { "basename": "jz9b02443_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6e609-86h31/files/jz9b02443_si_001.pdf" }, "pub_year": "2019", "author_list": "Naserifar, Saber and Goddard, William A., III" }, { "id": "https://authors.library.caltech.edu/records/5dav0-pat59", "eprint_id": 98676, "eprint_status": "archive", "datestamp": "2023-08-19 18:17:48", "lastmod": "2023-10-18 17:33:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Scanning electrochemical flow cell with online mass spectroscopy for accelerated screening of carbon dioxide reduction electrocatalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon dioxide reduction, high throughput experimentation, electrocatalysis, catalyst discovery, product detection", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: July 12, 2019; Revised: September 11, 2019; Published: September 16, 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515. The authors thank Apurva Mehta and Douglas G. Van Campen for assistance with collection of synchrotron XRD data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - co9b00130_si_001.pdf
", "abstract": "Electrochemical conversion of carbon dioxide into valuable chemicals or fuels is an increasingly important strategy for achieving carbon neutral technologies. The lack of a sufficiently active and selective electrocatalyst, particularly for synthesizing highly reduced products, motivates accelerated screening to evaluate new catalyst spaces. Traditional techniques, which couple electrocatalyst operation with analytical techniques to measure product distributions, enable screening throughput at 1\u201310 catalysts per day. In this paper, a combinatorial screening instrument is designed for MS detection of hydrogen, methane, and ethylene in quasi-real-time during catalyst operation experiments in an electrochemical flow cell. Coupled with experiment modeling, product detection during cyclic voltammetry (CV) enables modeling of the voltage-dependent partial current density for each detected product. We demonstrate the technique by using the well-established thin film Cu catalysts and by screening a Pd\u2013Zn composition library in carbonate-buffered aqueous electrolyte. The rapid product distribution characterization over a large range of overpotential makes the instrument uniquely suited for accelerating screening of electrocatalysts for the carbon dioxide reduction reaction.", "date": "2019-10-14", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "21", "number": "10", "publisher": "American Chemical Society", "pagerange": "692-704", "id_number": "CaltechAUTHORS:20190917-112624016", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190917-112624016", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.9b00130", "primary_object": { "basename": "co9b00130_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5dav0-pat59/files/co9b00130_si_001.pdf" }, "pub_year": "2019", "author_list": "Lai, Yungchieh; Jones, Ryan J. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/d73ps-a7842", "eprint_id": 98551, "eprint_status": "archive", "datestamp": "2023-08-19 18:14:17", "lastmod": "2023-10-20 22:13:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Reply to Head-Gordon and Paesani: Liquid water, a branched polymer with \u223c100-fs short-lived heterogeneous hydrogen bonds", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 National Academy of Sciences. Published under the PNAS license. \n\nPNAS first published September 10, 2019. \n\nS.N. was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. W.A.G. was supported by the Computational Materials Sciences Program funded by the US DOE, Office of Science, Basic Energy Sciences, under Award DE-SC00014607. The calculations were carried out on the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1548562. \n\nAuthor contributions: S.N. and W.A.G. designed research; S.N. performed research; S.N. and W.A.G. analyzed data; and S.N. and W.A.G. wrote the paper. \n\nThe authors declare no conflict of interest.\n\nPublished - 20257.full.pdf
", "abstract": "The letter by Head-Gordon and Paesani (hereafter HG-P) (1) contains several confusions about our results that we clarify here. \n\nThe title claiming that liquid water is not a dynamic polydisperse branched polymer is not supported by any information in their letter.", "date": "2019-10-08", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "116", "number": "41", "publisher": "National Academy of Sciences", "pagerange": "20257-20258", "id_number": "CaltechAUTHORS:20190910-124152105", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190910-124152105", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1352", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1913076116", "pmcid": "PMC6789962", "primary_object": { "basename": "20257.full.pdf", "url": "https://authors.library.caltech.edu/records/d73ps-a7842/files/20257.full.pdf" }, "pub_year": "2019", "author_list": "Naserifar, Saber and Goddard, William A., III" }, { "id": "https://authors.library.caltech.edu/records/r4d1f-kae97", "eprint_id": 99011, "eprint_status": "archive", "datestamp": "2023-08-19 18:12:35", "lastmod": "2023-10-18 17:47:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Unexpected Transitions Yield Interesting Science and High-Performance Materials", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 Published by Elsevier. \n\nAvailable online 2 October 2019. \n\nJ.M.G. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award number DE-SC0004993.", "abstract": "Solid-state materials are among the most promising enablers of future technologies and pose substantial challenges for accelerating scientific discovery. Combinatorial methods excel at finding surprising transitions in materials properties, and deeper materials understanding often follows.", "date": "2019-10-02", "date_type": "published", "publication": "Matter", "volume": "1", "number": "4", "publisher": "Elsevier", "pagerange": "790-791", "id_number": "CaltechAUTHORS:20191002-094950844", "issn": "2590-2385", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20191002-094950844", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.matt.2019.09.006", "pub_year": "2019", "author_list": "Gregoire, John M." }, { "id": "https://authors.library.caltech.edu/records/vy6jr-27165", "eprint_id": 88572, "eprint_status": "archive", "datestamp": "2023-08-22 02:27:11", "lastmod": "2023-10-18 22:09:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Jaramillo-Botero-Andres", "name": { "family": "Jaramillo-Botero", "given": "Andres" }, "orcid": "0000-0003-2844-0756" }, { "id": "An-Qi", "name": { "family": "An", "given": "Qi" }, "orcid": "0000-0003-4838-6232" }, { "id": "Ilyin-Daniil-V", "name": { "family": "Ilyin", "given": "Daniil V." }, "orcid": "0000-0003-3534-771X" }, { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "First principles-based multiscale atomistic methods for input into first principles nonequilibrium transport across interfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "quantum mechanics; reactive force fields; electron force field; molecular dynamics; multiscale simulation", "note": "\u00a9 2018 National Academy of Sciences. Published under the PNAS license. \n\nEdited by Katepalli R. Sreenivasan, New York University, New York, NY, and approved June 25, 2018 (received for review January 2, 2018). Published ahead of print August 3, 2018. \n\nThe work reported here on carbon dioxide reduction was supported by the Joint Center for Artificial Photosynthesis, a US Department of Energy (DOE) Energy Innovation Hub, which is supported through Office of Science of the DOE Award DE-SC0004993. The work on PQEq and polarizable reactive force field (ReaxPQ) was supported as part of the Computational Materials Sciences Program funded by DOE, Office of Science, Basic Energy Sciences Award DE-SC00014607 (program manager James Davenport). Other work on ReaxPQ for fuel cells was supported by National Science Foundation Grant CBET 1512759 (program manager Robert McCabe) and the new research using RexPoN is being continued with support from Office of Navel Research (N00014-18-1-2155). The computational resources are from Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1548562. \n\nAuthor contributions: W.A.G. designed research; T.C., A.J.-B., Q.A., D.V.I., and S.N. performed research; and T.C., A.J.-B., Q.A., D.V.I., S.N., and W.A.G. wrote the paper. \n\nThis article is a PNAS Direct Submission. \n\nThe authors declare no conflict of interest.\n\nPublished - 18193.full.pdf
", "abstract": "This issue of PNAS features \"nonequilibrium transport and mixing across interfaces,\" with several papers describing the nonequilibrium coupling of transport at interfaces, including mesoscopic and macroscopic dynamics in fluids, plasma, and other materials over scales from microscale to celestial. Most such descriptions describe the materials in terms of the density and equations of state rather than specific atomic structures and chemical processes. It is at interfacial boundaries where such atomistic information is most relevant. However, there is not yet a practical way to couple these phenomena with the atomistic description of chemistry. The starting point for including such information is the quantum mechanics (QM). However, practical QM calculations are limited to a hundred atoms for dozens of picoseconds, far from the scales required to inform the continuum level with the proper atomistic description. To bridge this enormous gap, we need to develop practical methods to extend the scale of the atomistic simulation by several orders of magnitude while retaining the level of QM accuracy in describing the chemical process. These developments would enable continuum modeling of turbulent transport at interfaces to incorporate the relevant chemistry. In this perspective, we will focus on recent progress in accomplishing these extensions in first principles-based atomistic simulations and the strategies being pursued to increase the accuracy of very large scales while dramatically decreasing the computational effort.", "date": "2019-09-10", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "116", "number": "37", "publisher": "National Academy of Sciences", "pagerange": "18193-18201", "id_number": "CaltechAUTHORS:20180803-131623344", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180803-131623344", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "Office of Naval Research (ONR)", "grant_number": "N00014-18-1-2155" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1312", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1800035115", "pmcid": "PMC6744898", "primary_object": { "basename": "18193.full.pdf", "url": "https://authors.library.caltech.edu/records/vy6jr-27165/files/18193.full.pdf" }, "pub_year": "2019", "author_list": "Cheng, Tao; Jaramillo-Botero, Andres; et el." }, { "id": "https://authors.library.caltech.edu/records/nmc36-dha41", "eprint_id": 95797, "eprint_status": "archive", "datestamp": "2023-08-22 02:24:43", "lastmod": "2023-10-20 20:35:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shen-Sheng", "name": { "family": "Shen", "given": "Sheng" } }, { "id": "Zhang-Xiaoyue", "name": { "family": "Zhang", "given": "Xiaoyue" } }, { "id": "Mubeen-S", "name": { "family": "Mubeen", "given": "Syed" } }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Stickney-J-L", "name": { "family": "Stickney", "given": "John L." } } ] }, "title": "Optimization of the nucleation-site density for the electrodeposition of cadmium sulfide on indium-tin-oxide", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Indium-tin-oxide; Nucleation and Growth; E-ALD; Cadmium Sulfide; Semiconductor Thin Films", "note": "\u00a9 2019 Published by Elsevier Ltd. \n\nReceived 5 April 2019, Revised 22 May 2019, Accepted 23 May 2019, Available online 24 May 2019. \n\nSupport from the National Science Foundation, DMR 1410109, is gratefully acknowledged. Thanks are extended to the Georgia Electron Microscopy for use of their SEM and Dr. Ryan Hilli's group for their spectrophotometer. The Joint Center for Artificial Photosynthesis at the California Institute of Technology, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (DE-SC0004993), provided assistance for Professor M. P. Soriaga. We thank Dr. Andrea Resta, Synchrotron Soleil, L'Orme des Merisiers, Gif-sur-Yvette, France for his contributions to this work. \n\nAuthor contributions: The manuscript was written through contributions of all authors. All authors have given approval to the final version of the manuscript.\n\nFunding sources: DMR 1410109.", "abstract": "Cadmium sulfide (CdS) is a preferred heterojunction partner for a number of chalcogenide-based solar cells. In view of this, interest has grown in the use of solution-based deposition techniques as an alternative route for the preparation of uniform ultrathin films of CdS. However, the quality of the electrodeposited CdS films on indium-tin oxide (ITO) remains far from optimal. This is because the ITO surface is electrochemically heterogeneous due to the presence of indium oxide; nucleation and further electrodeposition of CdS does not transpire on the oxided sites. Hence, only coarse-grained coatings, instead of homogeneous ultrathin films, are generated at un-pretreated ITO surfaces. In the present study, a mitigation of the amount of interfacial In oxide was attempted in order to increase the nucleation-site (indium-metal site) density. The procedure consisted of two steps: (i) Mild electrochemical reduction of the ITO to convert surface In(III) to In(0), followed by (ii) surface-limited redox replacement (SLRR) of In(0) by Cu via an aqueous solution of Cu^(2+). This procedure resulted in the formation of a high density of oxide-free Cu on which CdS nuclei would form; the thickness was such that optical transparency was largely undiminished. A ten-fold increase in CdS site density was observed, and that permitted the epitaxial growth of a second semiconductor, CdTe, atop the CdS film. The influences of applied potential and deposition time on nucleation-site sizes and densities were also studied.", "date": "2019-09-01", "date_type": "published", "publication": "Electrochimica Acta", "volume": "316", "publisher": "Elsevier", "pagerange": "105-112", "id_number": "CaltechAUTHORS:20190524-143304992", "issn": "0013-4686", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190524-143304992", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1410109" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.electacta.2019.05.120", "pub_year": "2019", "author_list": "Shen, Sheng; Zhang, Xiaoyue; et el." }, { "id": "https://authors.library.caltech.edu/records/pf1a4-zd677", "eprint_id": 96018, "eprint_status": "archive", "datestamp": "2023-08-19 17:42:39", "lastmod": "2023-10-20 20:48:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yalamanchili-Sisir", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Papadantonakis-K-M", "name": { "family": "Papadantonakis", "given": "Kimberly\u00a0M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Integration of electrocatalysts with silicon microcone arrays for minimization of optical and overpotential losses during sunlight-driven hydrogen evolution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Royal Society of Chemistry 2019. \n\nReceived 10th May 2019. Accepted 13th May 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: electrochemical measurements for all devices, and fabrication of p-Si/Co\u2013P devices was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the development and fabrication of p-Si and n^+p-Si/Pt \u03bc-cone arrays and reflection measurements were supported by the National Science Foundation (NSF) under NSF CA No. EEC-1041895. Additional support for this work was provided by the Lockheed Martin Corporation (Award 4103810021). Fabrication of Si \u03bc-cones was performed in the Kavli Nanoscience Institute (KNI) at Caltech, and we thank the KNI staff for their assistance during fabrication.\n\nSupplemental Material - c9se00294d1.pdf
", "abstract": "Microstructured photoelectrode morphologies can advantageously facilitate integration of optically absorbing electrocatalysts with semiconducting light absorbers, to maintain low overpotentials for fuel production without producing a substantial loss in photocurrent density. We report herein the use of arrays of antireflective, high-aspect-ratio Si microcones (\u03bc-cones), coupled with light-blocking Pt and Co\u2013P catalysts, as photocathodes for H_2 evolution. Thick (\u223c16 nm) layers of Pt or Co\u2013P deposited onto Si \u03bc-cone arrays yielded absolute light-limited photocurrent densities of \u223c32 mA cm^(\u22122), representing a reduction in light-limited photocurrent density of 6% relative to bare Si \u03bc-cone-array photocathodes, while maintaining high fill factors and low overpotentials for H_2 production from 0.50 M H_2SO_4(aq). The Si \u03bc-cone arrays were embedded in a flexible polymeric membrane and removed from the Si substrate, to yield flexible photocathodes consisting of polymer-embedded arrays of free-standing \u03bc-cones that evolved hydrogen from 0.50 M H_2SO_4(aq).", "date": "2019-09-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "3", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "2227-2236", "id_number": "CaltechAUTHORS:20190531-151359075", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190531-151359075", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Lockheed Martin", "grant_number": "4103810021" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/c9se00294d", "primary_object": { "basename": "c9se00294d1.pdf", "url": "https://authors.library.caltech.edu/records/pf1a4-zd677/files/c9se00294d1.pdf" }, "pub_year": "2019", "author_list": "Yalamanchili, Sisir; Kempler, Paul A.; et el." }, { "id": "https://authors.library.caltech.edu/records/9zpdp-xmm76", "eprint_id": 98767, "eprint_status": "archive", "datestamp": "2023-08-19 17:37:45", "lastmod": "2023-10-18 17:37:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gomes-C-P", "name": { "family": "Gomes", "given": "Carla" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John" }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Computational sustainability: computing for a better world and a sustainable future", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 held by authors/owners. \n\nWe thank the CompSustNet members for their many contributions to computational sustainability and the support of two NSF Expeditions in Computing awards (CNS-0832782 and CCF-1522054). We thank the anonymous reviewers for their suggestions to improve the manuscript. Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. government.", "abstract": "These are exciting times for computational sciences with the digital revolution permeating a variety of areas and radically transforming business, science, and our daily lives. The Internet and the World Wide Web, GPS, satellite communications, remote sensing, and smartphones are dramatically accelerating the pace of discovery, engendering globally connected networks of people and devices. The rise of practically relevant artificial intelligence (AI) is also playing an increasing part in this revolution, fostering e-commerce, social networks, personalized medicine, IBM Watson and AlphaGo, self-driving cars, and other groundbreaking transformations.", "date": "2019-09", "date_type": "published", "publication": "Communications of the ACM", "volume": "62", "number": "9", "publisher": "Association for Computing Machinery", "pagerange": "56-65", "id_number": "CaltechAUTHORS:20190920-080802370", "issn": "0001-0782", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190920-080802370", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CNS-0832782" }, { "agency": "NSF", "grant_number": "CCF-1522054" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1145/3339399", "pub_year": "2019", "author_list": "Gomes, Carla and Gregoire, John" }, { "id": "https://authors.library.caltech.edu/records/bfsgd-04x39", "eprint_id": 96601, "eprint_status": "archive", "datestamp": "2023-08-22 02:21:13", "lastmod": "2023-10-20 21:20:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jouny-M", "name": { "family": "Jouny", "given": "Matthew" }, "orcid": "0000-0002-5778-1106" }, { "id": "Lv-Jing-Jing", "name": { "family": "Lv", "given": "Jing-Jing" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Ko-Byung-Hee", "name": { "family": "Ko", "given": "Byung Hee" }, "orcid": "0000-0002-0934-5182" }, { "id": "Zhu-Jun-Jie", "name": { "family": "Zhu", "given": "Jun-Jie" }, "orcid": "0000-0002-8201-1285" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Jiao-Feng", "name": { "family": "Jiao", "given": "Feng" }, "orcid": "0000-0002-3335-3203" } ] }, "title": "Formation of carbon\u2013nitrogen bonds in carbon monoxide electrolysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Chemical engineering; Electrocatalysis", "note": "\u00a9 2019 Springer Nature Publishing AG. \n\nReceived 21 January 2019; Accepted 10 July 2019; Published 23 August 2019. \n\nF.J. would like to thank W. Luc for illustration assistance and E. Jeng for help with preparation of the anode. M.J. and J.-J.L. also thank B. Murphy and Z. J. Wang for help with GC\u2013MS. The experimental work was financially supported by the US Department of Energy under award no. DE-FE0029868. F.J. also thanks the National Science Foundation Faculty Early Career Development program (award no. CBET-1350911). J.-J.L. acknowledges financial support from Chinese Scholarship Council. T.C. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation grant no. ACI-1053575. This research used resources at the 8-ID Beamline of the National Synchrotron Light Source II, a US Department of Energy Office of Science User Facility operated by Brookhaven National Laboratory under contract no. DE-SC0012704. The authors acknowledge E. Stavitski (8-ID Beamline, NSLS-II, Brookhaven National Laboratory) for assistance in X-ray absorption spectroscopy measurements. \n\nData availability: The datasets generated during and/or analysed during the current study are available from the corresponding author on reasonable request. \n\nCode availability: The computational codes used in the current study are available from the corresponding author on reasonable request. \n\nCompeting interests: M.J., J.-J.L. and F.J. have filed a patent application (international patent application number: PCT/US 19/27012) that is based on the discovery presented in this work.\n\nSupplemental Material - 41557_2019_312_MOESM1_ESM.pdf
", "abstract": "The electroreduction of CO_2 is a promising technology for carbon utilization. Although electrolysis of CO_2 or CO_2-derived CO can generate important industrial multicarbon feedstocks such as ethylene, ethanol, n-propanol and acetate, most efforts have been devoted to promoting C\u2013C bond formation. Here, we demonstrate that C\u2013N bonds can be formed through co-electrolysis of CO and NH_3 with acetamide selectivity of nearly 40% at industrially relevant reaction rates. Full-solvent quantum mechanical calculations show that acetamide forms through nucleophilic addition of NH_3 to a surface-bound ketene intermediate, a step that is in competition with OH\u2013 addition, which leads to acetate. The C\u2013N formation mechanism was successfully extended to a series of amide products through amine nucleophilic attack on the ketene intermediate. This strategy enables us to form carbon\u2013heteroatom bonds through the electroreduction of CO, expanding the scope of products available from CO_2 reduction.", "date": "2019-09", "date_type": "published", "publication": "Nature Chemistry", "volume": "11", "number": "9", "publisher": "Nature Publishing Group", "pagerange": "846-851", "id_number": "CaltechAUTHORS:20190620-142925725", "issn": "1755-4330", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190620-142925725", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FE0029868" }, { "agency": "NSF", "grant_number": "CBET-1350911" }, { "agency": "Chinese Scholarship Council" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0012704" } ] }, "other_numbering_system": { "items": [ { "id": "1349", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41557-019-0312-z", "primary_object": { "basename": "41557_2019_312_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/bfsgd-04x39/files/41557_2019_312_MOESM1_ESM.pdf" }, "pub_year": "2019", "author_list": "Jouny, Matthew; Lv, Jing-Jing; et el." }, { "id": "https://authors.library.caltech.edu/records/g2dzs-91y42", "eprint_id": 96790, "eprint_status": "archive", "datestamp": "2023-08-19 17:27:40", "lastmod": "2023-10-20 21:31:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Meng", "name": { "family": "Lin", "given": "Meng" }, "orcid": "0000-0001-7785-749X" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Singh-M-R", "name": { "family": "Singh", "given": "Meenesh R." }, "orcid": "0000-0002-3638-8866" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "An Experimental- and Simulation-Based Evaluation on the CO_2 Utilization Efficiency in Aqueous-based Electrochemical CO_2 Reduction Reactors with Ion-Selective Membranes", "ispublished": "pub", "full_text_status": "public", "keywords": "electrochemical CO_2 reduction, CO_2 utilization efficiency, ion-exchange membrane, modeling, ionic conductivity, bipolar membrane", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: May 17, 2019; Accepted: June 27, 2019; Published: June 27, 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993, in collaboration with the Materials and Systems Engineering Laboratory at the University of Illinois at Chicago. Meng Lin acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, Grant P2ELP2_178290. M.R.S. acknowledges the support from the Department of Chemical Engineering at the University of Illinois at Chicago. \n\nAuthor Contributions: M.L. and L.H. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ae9b00986_si_001.pdf
", "abstract": "The CO_2 utilization efficiency of three types of electrochemical CO2 reduction (CO_2R) reactors using different ion-selective membranes, including anion exchange membrane (AEM), cation exchange membrane (CEM), and bipolar membrane (BPM), was studied quantitively via both experimental and simulation methods. The operating current density of the CO_2R reactors was chosen to be between 10 \u2013 50 mA cm^(-2) to be relevant for solar-fuel devices with relatively low photon flux from sunlight. In the AEM based CO_2R reactor with a 6-electron per carbon CO_2R at the cathode surface, an upper limit of 14.4% for the CO_2 utilization efficiency was revealed by modeling and validated by experimental measurements in CO_2 saturated aqueous electrolytes without any buffer electrolyte. Improvements in CO_2 utilization efficiency were observed when additional buffer electrolyte was added into the aqueous solution, especially in solutions with low bicarbonate concentrations. The effects of the feed rate of the input CO_2 stream, the Faradaic Efficiency (FE) and the participating electron numbers of the cathode reaction on the CO_2 utilization efficiency was also studied in the AEM based CO_2R reactor. The CEM based CO_2R reactor exhibited low CO_2 utilization efficiency with re-circulation between the catholyte and the anolyte, and was unsustainable due to the cation depletion from the anolyte without any re-circulation. The BPM based CO_2R reactor operated continuously without a significant increase in the cell voltage and exhibited significantly higher CO_2 utilization efficiency, up to 61.4%, as compared to the AEM based CO_2R reactors. Diffusive CO_2 loss across the BPM resulted in relatively low CO_2 utilization efficiency at low operating current densities. Modeling and simulation also provided target BPM properties for higher CO_2 utilization efficiency and efficient cell operation.", "date": "2019-08-26", "date_type": "published", "publication": "ACS Applied Energy Materials", "volume": "2", "number": "8", "publisher": "American Chemical Society", "pagerange": "5843-5850", "id_number": "CaltechAUTHORS:20190627-130708138", "issn": "2574-0962", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190627-130708138", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2ELP2_178290" }, { "agency": "University of Illinois, Chicago" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsaem.9b00986", "primary_object": { "basename": "ae9b00986_si_001.pdf", "url": "https://authors.library.caltech.edu/records/g2dzs-91y42/files/ae9b00986_si_001.pdf" }, "pub_year": "2019", "author_list": "Lin, Meng; Han, Lihao; et el." }, { "id": "https://authors.library.caltech.edu/records/6xwga-55241", "eprint_id": 96580, "eprint_status": "archive", "datestamp": "2023-08-19 17:25:14", "lastmod": "2023-10-20 21:19:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nunez-P-D", "name": { "family": "Nunez", "given": "Paul" }, "orcid": "0000-0001-7039-0516" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Piercy-B-D", "name": { "family": "Piercy", "given": "Brandon D." }, "orcid": "0000-0002-9943-6773" }, { "id": "Roske-C-W", "name": { "family": "Roske", "given": "Christopher W." } }, { "id": "Cab\u00e1n-Acevedo-M", "name": { "family": "Cab\u00e1n-Acevedo", "given": "Miguel" }, "orcid": "0000-0003-0054-8044" }, { "id": "Losego-M-D", "name": { "family": "Losego", "given": "Mark D." }, "orcid": "0000-0002-9810-9834" }, { "id": "Konezny-S-J", "name": { "family": "Konezny", "given": "Steven J." }, "orcid": "0000-0003-1487-0931" }, { "id": "Fermin-D-J", "name": { "family": "Fermin", "given": "David J." }, "orcid": "0000-0002-0376-5506" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Characterization of Electronic Transport through Amorphous TiO_2 Produced by Atomic-Layer Deposition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: May 9, 2019; Revised: June 14, 2019; Published: June 19, 2019. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. P.D.N. and C.W.R. thank the National Science Foundation for graduate research fellowships. C.W.R. also thanks the Link Energy Foundation for a graduate research fellowship. Research was in part carried out at the Molecular Materials Resource Center of the Beckman Institute and at the Microanalysis Center of the California Institute of Technology. D.J.F. acknowledges the financial support by the UK Engineering and Physical Sciences Research Council through the PVTEAM programme (EP/L017792/1). We thank Dr. Y. Guan for SIMS measurements, Dr. Angelo Di Bilio and Dr. Paul H. Oyala for EPR measurements, and K. Papadantonakis for assistance with editing this manuscript. S.H. and S.J.K. acknowledge the start-up support from the Tomkat Foundation. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp9b04434_si_001.pdf
", "abstract": "Electrical transport in amorphous titanium dioxide (a-TiO_2) thin films, deposited by atomic layer deposition (ALD), and across heterojunctions of p+-Si|a-TiO_2|metal substrates that had various top metal contacts has been characterized by ac conductivity, temperature-dependent dc conductivity, space-charge-limited current spectroscopy, electron paramagnetic resonance (EPR) spectroscopy, X-ray photoelectron spectroscopy, and current density versus voltage (J\u2013V) characteristics. Amorphous TiO_2 films were fabricated using either tetrakis(dimethylamido)-titanium with a substrate temperature of 150 \u00b0C or TiCl_4 with a substrate temperature of 50, 100, or 150 \u00b0C. EPR spectroscopy of the films showed that the Ti^(3+) concentration varied with the deposition conditions and increases in the concentration of Ti^(3+) in the films correlated with increases in film conductivity. Valence band spectra for the a-TiO_2 films exhibited a defect-state peak below the conduction band minimum (CBM) and increases in the intensity of this peak correlated with increases in the Ti^(3+) concentration measured by EPR as well as with increases in film conductivity. The temperature-dependent conduction data showed Arrhenius behavior at room temperature with an activation energy that decreased with decreasing temperature, suggesting that conduction did not occur primarily through either the valence or conduction bands. The data from all of the measurements are consistent with a Ti^(3+) defect-mediated transport mode involving a hopping mechanism with a defect density of 10^(19) cm^(\u20133), a 0.83 wide defect band centered 1.47 eV below the CBM, and a free-electron concentration of 10^(16) cm^(\u20133). The data are consistent with substantial room-temperature anodic conductivity resulting from the introduction of defect states during the ALD fabrication process as opposed to charge transport intrinsically associated with the conduction band of TiO_2.", "date": "2019-08-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "123", "number": "33", "publisher": "American Chemical Society", "pagerange": "20116-20129", "id_number": "CaltechAUTHORS:20190620-093003082", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190620-093003082", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Link Foundation" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/L017792/1" }, { "agency": "Tomkat Foundation" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.9b04434", "primary_object": { "basename": "jp9b04434_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6xwga-55241/files/jp9b04434_si_001.pdf" }, "pub_year": "2019", "author_list": "Nunez, Paul; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/q468e-dwg50", "eprint_id": 95433, "eprint_status": "archive", "datestamp": "2023-08-19 17:19:44", "lastmod": "2023-10-20 20:13:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Sebastian-J-R", "name": { "family": "Lee", "given": "Sebastian J. R." }, "orcid": "0000-0001-7006-9378" }, { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Analytical Gradients for Projection-Based Wavefunction-in-DFT Embedding", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 Published under license by AIP Publishing. \n\nSubmitted: 13 May 2019; Accepted: 3 July 2019; Published Online: 9 August 2019. \n\nWe thank Matthew Welborn for helpful discussions. This material is based on the work supported by the U.S. Army Research Laboratory under Grant No. W911NF-12-2-0023 (S.J.R.L.). S.J.R.L. thanks the Caltech Resnick Sustainability Institute for a graduate fellowship. T.F.M. and F.R.M. acknowledge joint support from the DOE (Award No. DEFOA-0001912), and F.R.M. acknowledges support from the Engineering and Physical Sciences Research Council for funding (No. EP/M013111/1).\n\nPublished - 1.5109882.pdf
Submitted - 1903.05830.pdf
Supplemental Material - Supp_material.zip
", "abstract": "Projection-based embedding provides a simple, robust, and accurate approach for describing a small part of a chemical system at the level of a correlated wavefunction (WF) method, while the remainder of the system is described at the level of density functional theory (DFT). Here, we present the derivation, implementation, and numerical demonstration of analytical nuclear gradients for projection-based wavefunction-in-density functional theory (WF-in-DFT) embedding. The gradients are formulated in the Lagrangian framework to enforce orthogonality, localization, and Brillouin constraints on the molecular orbitals. An important aspect of the gradient theory is that WF contributions to the total WF-in-DFT gradient can be simply evaluated using existing WF gradient implementations without modification. Another simplifying aspect is that Kohn-Sham (KS) DFT contributions to the projection-based embedding gradient do not require knowledge of the WF calculation beyond the relaxed WF density. Projection-based WF-in-DFT embedding gradients are thus easily generalized to any combination of WF and KS-DFT methods. We provide a numerical demonstration of the method for several applications, including a calculation of a minimum energy pathway for a hydride transfer in a cobalt-based molecular catalyst using the nudged-elastic-band method at the coupled-cluster single double-in-DFT level of theory, which reveals large differences from the transition state geometry predicted using DFT.", "date": "2019-08-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "151", "number": "6", "publisher": "American Institute of Physics", "pagerange": "Art. No. 064112", "id_number": "CaltechAUTHORS:20190513-111036074", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190513-111036074", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-12-2-0023" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001912" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1063/1.5109882", "primary_object": { "basename": "1.5109882.pdf", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/1.5109882.pdf" }, "related_objects": [ { "basename": "1903.05830.pdf", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/1903.05830.pdf" }, { "basename": "Supp_material.zip", "url": "https://authors.library.caltech.edu/records/q468e-dwg50/files/Supp_material.zip" } ], "pub_year": "2019", "author_list": "Lee, Sebastian J. R.; Ding, Feizhi; et el." }, { "id": "https://authors.library.caltech.edu/records/w355h-yxq78", "eprint_id": 97511, "eprint_status": "archive", "datestamp": "2023-08-22 02:05:43", "lastmod": "2023-10-18 16:01:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Haochen", "name": { "family": "Zhang", "given": "Haochen" }, "orcid": "0000-0002-2774-5868" }, { "id": "Chang-Xiaoxia", "name": { "family": "Chang", "given": "Xiaoxia" }, "orcid": "0000-0001-6598-6083" }, { "id": "Chen-Jingguang-G", "name": { "family": "Chen", "given": "Jingguang G." }, "orcid": "0000-0002-9592-2635" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Xu-Bingjun", "name": { "family": "Xu", "given": "Bingjun" }, "orcid": "0000-0002-2303-257X" }, { "id": "Cheng-Mu-Jeng", "name": { "family": "Cheng", "given": "Mu-Jeng" }, "orcid": "0000-0002-8121-0485" }, { "id": "Lu-Qi", "name": { "family": "Lu", "given": "Qi" }, "orcid": "0000-0002-0380-2629" } ] }, "title": "Computational and experimental demonstrations of one-pot tandem catalysis for electrochemical carbon dioxide reduction to methane", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrocatalysis; Electrochemistry", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 16 December 2018; Accepted 30 June 2019; Published 26 July 2019. \n\nData availability: The data that support the findings of this study are available from the corresponding author upon request. \n\nThis work is supported by the National Key Research and Development Program of China (grant number 2017YFA0208200) and the National Natural Science Foundation of China (grant numbers 21872079, 21606142). W.A.G. is supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. X.C. and B.X. acknowledge the support of the National Science Foundation CAREER Program (Award No. CBET-1651625). M.-J.C. acknowledges financial support from the Ministry of Science and Technology of the Republic of China under grant no. MOST 107\u20132113-M-006\u2013008-MY2. \n\nAuthor Contributions: H.Z., M.-J.C., and Q.L. conceived and designed both computational and electrochemical investigations and wrote the manuscript. H.Z. and M.-J.C. performed DFT calculations and analyzed the data. H.Z. and Q.L. carried out the electrocatalytic tests and analyzed the results. H.Z. and Q.L. performed electron microscopy studies, FIB, XPS, and analyzed these data. X.C. and B.X. performed ATR-SEIRAS experiments and analyzed the results. J.G.C., W.A.G., and B.X. contributed to data analysis and writing of this manuscript. \n\nThe authors declare no competing interests.\n\nPublished - s41467-019-11292-9.pdf
Supplemental Material - 41467_2019_11292_MOESM1_ESM.pdf
", "abstract": "Electroreduction of carbon dioxide to hydrocarbons and oxygenates on copper involves reduction to a carbon monoxide adsorbate followed by further transformation to hydrocarbons and oxygenates. Simultaneous improvement of these processes over a single reactive site is challenging due to the linear scaling relationship of the binding strength of key intermediates. Herein, we report improved electroreduction of carbon dioxide by exploiting a one-pot tandem catalysis mechanism based on computational and electrochemical investigations. By constructing a well-defined copper-modified silver surface, adsorbed carbon monoxide generated on the silver sites is proposed to migrate to surface copper sites for the subsequent reduction to methane, which is consistent with insights gained from operando attenuated total reflectance surface enhanced infrared absorption spectroscopic investigations. Our results provide a promising approach for designing carbon dioxide electroreduction catalysts to enable one-pot reduction of products beyond carbon monoxide and formate.", "date": "2019-07-26", "date_type": "published", "publication": "Nature Communications", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 3340", "id_number": "CaltechAUTHORS:20190730-090851748", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190730-090851748", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFA0208200" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21872079" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21606142" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-1651625" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "107-2113-M-006-008-MY2" } ] }, "other_numbering_system": { "items": [ { "id": "1345", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-019-11292-9", "pmcid": "PMC6659690", "primary_object": { "basename": "41467_2019_11292_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/w355h-yxq78/files/41467_2019_11292_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41467-019-11292-9.pdf", "url": "https://authors.library.caltech.edu/records/w355h-yxq78/files/s41467-019-11292-9.pdf" } ], "pub_year": "2019", "author_list": "Zhang, Haochen; Chang, Xiaoxia; et el." }, { "id": "https://authors.library.caltech.edu/records/dm3mv-q1b76", "eprint_id": 97441, "eprint_status": "archive", "datestamp": "2023-08-19 16:52:58", "lastmod": "2023-10-20 22:05:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Tracking materials science data lineage to manage millions of materials experiments and analyses", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 22 December 2018; Accepted 26 June 2019; Published 26 July 2019. \n\nData availability: The data sets generated during and/or analyzed during the current study are available in the HTE-JCAP repository, https://htejcap.org or https://doi.org/10.25989/es8t-kswe. Summary tables of plates and compositions are available at https://doi.org/10.22002/D1.1256. \n\nThis study and the acquisition of all data is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy (Award No. DE-SC0004993). The development of database export algorithms was also supported by a grant from the Toyota Research Institute through the Accelerated Materials Design and Discovery program. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. \n\nAuthor Contributions: E.S. designed, developed, and maintained the IT infrastructure, data management system, database, searchable index, and the web UI that runs MEAD. E.S., J.G., S.K.S., and D.G. designed data management protocols. J.G., S.K.S., D.G., and H.S. designed, developed, and verified data analysis algorithms. The paper was written by E.S. and J.G. with contributions from H.S. \n\nThe authors declare no competing interests.\n\nPublished - s41524-019-0216-x.pdf
Supplemental Material - 41524_2019_216_MOESM1_ESM.pdf
Supplemental Material - 41524_2019_216_MOESM2_ESM.csv
Supplemental Material - 41524_2019_216_MOESM3_ESM.txt
", "abstract": "In an era of rapid advancement of algorithms that extract knowledge from data, data and metadata management are increasingly critical to research success. In materials science, there are few examples of experimental databases that contain many different types of information, and compared with other disciplines, the database sizes are relatively small. Underlying these issues are the challenges in managing and linking data across disparate synthesis and characterization experiments, which we address with the development of a lightweight data management framework that is generally applicable for experimental science and beyond. Five years of managing experiments with this system has yielded the Materials Experiment and Analysis Database (MEAD) that contains raw data and metadata from millions of materials synthesis and characterization experiments, as well as the analysis and distillation of that data into property and performance metrics via software in an accompanying open source repository. The unprecedented quantity and diversity of experimental data are searchable by experiment and analysis attributes generated by both researchers and data processing software. The search web interface allows users to visualize their search results and download zipped packages of data with full annotations of their lineage. The enormity of the data provides substantial challenges and opportunities for incorporating data science in the physical sciences, and MEAD's data and algorithm management framework will foster increased incorporation of automation and autonomous discovery in materials and chemistry research.", "date": "2019-07-26", "date_type": "published", "publication": "npj Computational Materials", "volume": "5", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 79", "id_number": "CaltechAUTHORS:20190726-101520787", "issn": "2057-3960", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190726-101520787", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Toyota Research Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41524-019-0216-x", "primary_object": { "basename": "41524_2019_216_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/dm3mv-q1b76/files/41524_2019_216_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41524_2019_216_MOESM2_ESM.csv", "url": "https://authors.library.caltech.edu/records/dm3mv-q1b76/files/41524_2019_216_MOESM2_ESM.csv" }, { "basename": "41524_2019_216_MOESM3_ESM.txt", "url": "https://authors.library.caltech.edu/records/dm3mv-q1b76/files/41524_2019_216_MOESM3_ESM.txt" }, { "basename": "s41524-019-0216-x.pdf", "url": "https://authors.library.caltech.edu/records/dm3mv-q1b76/files/s41524-019-0216-x.pdf" } ], "pub_year": "2019", "author_list": "Soedarmadji, Edwin; Stein, Helge S.; et el." }, { "id": "https://authors.library.caltech.edu/records/3ry91-69x44", "eprint_id": 96498, "eprint_status": "archive", "datestamp": "2023-08-19 16:50:50", "lastmod": "2023-10-20 21:14:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yalu", "name": { "family": "Chen", "given": "Yalu" }, "orcid": "0000-0002-0589-845X" }, { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Identifying Active Sites for CO\u2082 Reduction on Dealloyed Gold Surfaces by Combining Machine Learning with Multiscale Simulations", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: May 8, 2019; Published: June 18, 2019.\n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work uses the computational resources of Caltech High Performance Computing Center (HPC). \n\nThe authors declare no competing financial interest.\n\nUpdated - ja9b04956_si_001.pdf
", "abstract": "Gold nanoparticles (AuNPs) and dealloyed Au_3Fe core\u2013shell NP surfaces have been shown to have dramatically improved performance in reducing CO_2 to CO (CO2RR), but the surface features responsible for these improvements are not known. The active sites cannot be identified with surface science experiments, and quantum mechanics (QM) is not practical for the 10\u202f000 surface sites of a 10 nm NP (200\u202f000 bulk atoms). Here, we combine machine learning, multiscale simulations, and QM to predict the performance (a-value) of all 5000\u201310\u202f000 surface sites on AuNPs and dealloyed Au surfaces. We then identify the optimal active sites for CO2RR on dealloyed gold surfaces with dramatically reduced computational effort. This approach provides a powerful tool to visualize the catalytic activity of the whole surface. Comparing the a-value with descriptors from experiment, computation, or theory should provide new ways to guide the design of high-performance electrocatalysts for applications in clean energy conversion.", "date": "2019-07-24", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "29", "publisher": "American Chemical Society", "pagerange": "11651-11657", "id_number": "CaltechAUTHORS:20190618-103437881", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190618-103437881", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1341", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.9b04956", "primary_object": { "basename": "ja9b04956_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3ry91-69x44/files/ja9b04956_si_001.pdf" }, "pub_year": "2019", "author_list": "Chen, Yalu; Huang, Yufeng; et el." }, { "id": "https://authors.library.caltech.edu/records/zqrkn-f3w82", "eprint_id": 97288, "eprint_status": "archive", "datestamp": "2023-08-19 16:48:59", "lastmod": "2023-10-20 22:03:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ament-S-E", "name": { "family": "Ament", "given": "Sebastian E." } }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Boyd-D-A", "name": { "family": "Boyd", "given": "David A." } }, { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Gomes-C-P", "name": { "family": "Gomes", "given": "Carla P." } } ] }, "title": "Multi-component background learning automates signal detection for spectroscopic data", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 18 February 2019; Accepted 26 June 2019; Published 19 July 2019. \n\nThe development of the MCBL algorithm, inkjet printing synthesis, and Raman measurements were supported by a an Accelerated Materials Design and Discovery grant from the Toyota Research Institute. Initial design of the algorithm and data procurement were supported by the NSF Expedition award for Computational Sustainability CCF-1522054 and by Army Research Office (ARO) award W911-NF-14-1-0498. The implementation of the algorithm for automated, unsupervised operation was supported by MURI/AFOSR grant FA9550. Compute infrastructure was provided by NSF award CNS-0832782 and by ARO DURIP award W911NF-17-1-0187. The sputter deposition and XRD measurements were supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The authors thank Edwin Soedarmadji for assistance with data management. \n\nData availability: The datasets analyzed during the current study are available in the Caltech Data repository: XRD at https://doi.org/10.22002/D1.1178, https://data.caltech.edu/records/1178 and Raman at https://doi.org/10.22002/D1.1179, https://data.caltech.edu/records/1179. \n\nCode availability: The codes pertaining to the current study will be available at http://www.cs.cornell.edu/gomes/udiscoverit/. \n\nAuthor Contributions: C.G. and J.G. identified the problem to be solved. S.A. and C.G. conceptualized the model. S.A. developed the mathematical framework, designed the algorithm, and implemented it. J.G., H.S. and D.G. inspected results. S.A., D.G. and J.G. created visualizations of the results. L.Z. performed materials synthesis and data acquisition for XRD data. J.H. synthesized materials for Raman measurements. D.B. and M.U. acquired and provided the Raman data. S.A., J.G., C.G., H.S. and D.G. wrote the paper. \n\nThe authors declare no competing interests.\n\nPublished - s41524-019-0213-0.pdf
", "abstract": "Automated experimentation has yielded data acquisition rates that supersede human processing capabilities. Artificial Intelligence offers new possibilities for automating data interpretation to generate large, high-quality datasets. Background subtraction is a long-standing challenge, particularly in settings where multiple sources of the background signal coexist, and automatic extraction of signals of interest from measured signals accelerates data interpretation. Herein, we present an unsupervised probabilistic learning approach that analyzes large data collections to identify multiple background sources and establish the probability that any given data point contains a signal of interest. The approach is demonstrated on X-ray diffraction and Raman spectroscopy data and is suitable to any type of data where the signal of interest is a positive addition to the background signals. While the model can incorporate prior knowledge, it does not require knowledge of the signals since the shapes of the background signals, the noise levels, and the signal of interest are simultaneously learned via a probabilistic matrix factorization framework. Automated identification of interpretable signals by unsupervised probabilistic learning avoids the injection of human bias and expedites signal extraction in large datasets, a transformative capability with many applications in the physical sciences and beyond.", "date": "2019-07-19", "date_type": "published", "publication": "npj Computational Materials", "volume": "5", "publisher": "Nature Research", "pagerange": "Art. No. 77", "id_number": "CaltechAUTHORS:20190719-095139134", "issn": "2057-3960", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190719-095139134", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Toyota Research Institute" }, { "agency": "NSF", "grant_number": "CCF-1522054" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911-NF-14-1-0498" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550" }, { "agency": "NSF", "grant_number": "CNS-0832782" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0187" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41524-019-0213-0", "primary_object": { "basename": "s41524-019-0213-0.pdf", "url": "https://authors.library.caltech.edu/records/zqrkn-f3w82/files/s41524-019-0213-0.pdf" }, "pub_year": "2019", "author_list": "Ament, Sebastian E.; Stein, Helge S.; et el." }, { "id": "https://authors.library.caltech.edu/records/04tg0-jnh19", "eprint_id": 94396, "eprint_status": "archive", "datestamp": "2023-08-19 16:40:37", "lastmod": "2023-10-20 17:56:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" } ] }, "title": "Functional mapping reveals mechanistic clusters for OER catalysis across (Cu\u2013Mn\u2013Ta\u2013Co\u2013Sn\u2013Fe)O_x composition and pH space", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Royal Society of Chemistry. \n\nThe article was received on 21 Dec 2018, accepted on 27 Mar 2019 and first published on 27 Mar 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We thank K. Kan for collecting XRF data. \n\nConflicts of interest: There are no conflicts to declare.\n\nSupplemental Material - c8mh01641k1_si.pdf
", "abstract": "Identification of stable electrocatalysts for the oxygen evolution reaction (OER) remains a primary challenge in materials for energy. pH-Dependent activity is known for very few catalysts, prompting our exploration of a broad range of catalysts using high throughput experiments and data science. This approach enables the largest screening of OER activity and operational stability to date, as illustrated through investigation of the (Cu\u2013Mn\u2013Ta\u2013Co\u2013Sn\u2013Fe)O_x composition space as 15 unique quaternary composition spaces. In total 2121 compositions are tested between pH 3 and 13, creating an extensive dataset whose interpretation requires development and application of data science to provide insights that are both beyond the standard composition\u2013activity relationships and beyond human interpretation due to the dimensionality of the dataset. Three distinct classes of OER catalysts are identified with respect to pH-dependent activity and stability. The large-scale screening reveals a new class of Co-rich OER catalysts that can be compositionally tailored to a specified pH and perform on par with state-of-the-art acid OER catalysts.", "date": "2019-07-01", "date_type": "published", "publication": "Materials Horizons", "volume": "6", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1251-1258", "id_number": "CaltechAUTHORS:20190403-094432903", "issn": "2051-6347", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190403-094432903", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c8mh01641k", "primary_object": { "basename": "c8mh01641k1_si.pdf", "url": "https://authors.library.caltech.edu/records/04tg0-jnh19/files/c8mh01641k1_si.pdf" }, "pub_year": "2019", "author_list": "Stein, Helge S.; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/2qcp2-36392", "eprint_id": 97575, "eprint_status": "archive", "datestamp": "2023-08-19 16:33:54", "lastmod": "2023-10-18 16:06:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gomes-C-P", "name": { "family": "Gomes", "given": "Carla P." } }, { "id": "Selman-B", "name": { "family": "Selman", "given": "Bart" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Artificial intelligence for materials discovery", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 Materials Research Society. \n\nPublished online by Cambridge University Press: 12 July 2019. \n\nThis work was supported by an award from the Toyota Research Institute; NSF Award Nos. CCF-1522054 and CNS-0832782 (Expeditions), CNS-1059284 (Infrastructure), and IIS-1344201 (INSPIRE); ARO Award No. W911-NF-14-1-0498; AFOSR Multidisciplinary University Research Initiatives (MURI) Program FA9550-18-1-0136; and US DOE Award No. DE-SC0004993.", "abstract": "Continued progress in artificial intelligence (AI) and associated demonstrations of superhuman performance have raised the expectation that AI can revolutionize scientific discovery in general and materials science specifically. We illustrate the success of machine learning (ML) algorithms in tasks ranging from machine vision to game playing and describe how existing algorithms can also be impactful in materials science, while noting key limitations for accelerating materials discovery. Issues of data scarcity and the combinatorial nature of materials spaces, which limit application of ML techniques in materials science, can be overcome by exploiting the rich scientific knowledge from physics and chemistry using additional AI techniques such as reasoning, planning, and knowledge representation. The integration of these techniques in materials-intelligent systems will enable AI governance of the scientific method and autonomous scientific discovery.", "date": "2019-07", "date_type": "published", "publication": "MRS Bulletin", "volume": "44", "number": "7", "publisher": "Materials Research Society", "pagerange": "538-544", "id_number": "CaltechAUTHORS:20190801-085714793", "issn": "0883-7694", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190801-085714793", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Toyota Research Institute" }, { "agency": "NSF", "grant_number": "CCF-1522054" }, { "agency": "NSF", "grant_number": "CNS-0832782" }, { "agency": "NSF", "grant_number": "CNS-1059284" }, { "agency": "NSF", "grant_number": "IIS-1344201" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911-NF-14-1-0498" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1557/mrs.2019.158", "pub_year": "2019", "author_list": "Gomes, Carla P.; Selman, Bart; et el." }, { "id": "https://authors.library.caltech.edu/records/02de2-1e171", "eprint_id": 96792, "eprint_status": "archive", "datestamp": "2023-08-19 16:30:37", "lastmod": "2023-10-20 21:31:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jermyn-Adam-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" } ] }, "title": "Transport of hot carriers in plasmonic nanostructures", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\nReceived 6 March 2019; published 8 July 2019. \n\nThis material is based upon work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, as well as the Center for Computational Innovations at Rensselaer Polytechnic Institute. A.S.J. thanks the UK Marshall Commission and the US Goldwater Scholarship for financial support. G.T. acknowledges support from the Swiss National Science Foundation, Early Postdoctoral Mobility Fellowship No. P2EZP2-159101. P.N. acknowledges start-up funding from the Harvard John A. Paulson School of Engineering and Applied Sciences and partial support from the Harvard University Center for the Environment (HUCE). R.S. acknowledges start-up funding from the Department of Materials Science and Engineering at Rensselaer Polytechnic Institute.\n\nPublished - PhysRevMaterials.3.075201.pdf
Submitted - 1707.07060.pdf
", "abstract": "Plasmonic hot carrier devices extract excited carriers from metal nanostructures before equilibration and have the potential to surpass semiconductor light absorbers. However their efficiencies have so far remained well below theoretical limits, which necessitates quantitative prediction of carrier transport and energy loss in plasmonic structures to identify and overcome bottlenecks in carrier harvesting. Here, we present a theoretical and computational framework, nonequilibrium scattering in space and energy (NESSE), to predict the spatial evolution of carrier energy distributions that combines the best features of phase-space (Boltzmann) and particle-based (Monte Carlo) methods. Within the NESSE framework, we bridge first-principles electronic structure predictions of plasmon decay and carrier collision integrals at the atomic scale, with electromagnetic field simulations at the nano- to mesoscale. Finally, we apply NESSE to predict spatially-resolved energy distributions of photoexcited carriers that impact the surface of experimentally realizable plasmonic nanostructures at length scales ranging from tens to several hundreds of nanometers, enabling first-principles design of hot carrier devices.", "date": "2019-07", "date_type": "published", "publication": "Physical Review Materials", "volume": "3", "number": "7", "publisher": "American Physical Society", "pagerange": "Art. No. 075201", "id_number": "CaltechAUTHORS:20190627-130903657", "issn": "2475-9953", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190627-130903657", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "UK Marshall Commission" }, { "agency": "Barry M. Goldwater Scholarship" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2-159101" }, { "agency": "Harvard University" }, { "agency": "Rensselaer Polytechnic Institute" } ] }, "other_numbering_system": { "items": [ { "id": "1343", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevMaterials.3.075201", "primary_object": { "basename": "PhysRevMaterials.3.075201.pdf", "url": "https://authors.library.caltech.edu/records/02de2-1e171/files/PhysRevMaterials.3.075201.pdf" }, "related_objects": [ { "basename": "1707.07060.pdf", "url": "https://authors.library.caltech.edu/records/02de2-1e171/files/1707.07060.pdf" } ], "pub_year": "2019", "author_list": "Jermyn, Adam S.; Tagliabue, Giulia; et el." }, { "id": "https://authors.library.caltech.edu/records/2ndpa-r2629", "eprint_id": 97941, "eprint_status": "archive", "datestamp": "2023-08-19 16:06:40", "lastmod": "2023-10-18 16:54:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gomes-Carla-P", "name": { "family": "Gomes", "given": "Carla P." }, "orcid": "0000-0002-4441-7225" }, { "id": "Bai-Junwen", "name": { "family": "Bai", "given": "Junwen" } }, { "id": "Xue-Yexiang", "name": { "family": "Xue", "given": "Yexiang" } }, { "id": "Bjorck-Johan", "name": { "family": "Bjorck", "given": "Johan" } }, { "id": "Rappazzo-Brendan-H", "name": { "family": "Rappazzo", "given": "Brendan" } }, { "id": "Ament-Sebastian-E", "name": { "family": "Ament", "given": "Sebastian" } }, { "id": "Bernstein-Richard-B", "name": { "family": "Bernstein", "given": "Richard" } }, { "id": "Kong-Shufeng", "name": { "family": "Kong", "given": "Shufeng" } }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "van-Dover-R-Bruce", "name": { "family": "van Dover", "given": "R. Bruce" }, "orcid": "0000-0002-6166-5650" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "CRYSTAL: a multi-agent AI system for automated mapping of materials' crystal structures", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2019 Materials Research Society. \n\nReceived 18 January 2019; accepted 8 April 2019. \n\nThis work was supported by NSF awards CCF-1522054 and CNS-0832782 (Expeditions), CNS-1059284 (Infrastructure), and IIS-1344201 (INSPIRE); ARO awards W911NF-14-1-0498 and W911NF-17-1-0187; AFOSR Multidisciplinary University Research Initiatives (MURI) Program FA9550-18-1-0136, Toyota Research Institute award; and US DOE Award No. DE-SC0004993. Use of SSRL is supported by DOE Contract No. DE-AC02-76SF00515. Use of CHESS is supported by the NSF award DMR-1332208. The authors thank A. Mehta, D. G. Van Campen, M. Tague, and D. Dale for assistance with data collection. \n\nAuthor contributions: The authors' contributions are as follows: C.P.G., R.B.vD., and J.M.G. conceived and managed the project. C.P.G. conceived CRYSTAL'S multiple knowledge source approach. J.Ba., JBj., C.P.G., and Y.X. designed the bots' algorithms. J.Ba., C.P.G., J.M.G., B.H.R., and Y.X. designed the Diagram Rendering bot. J.Ba. implemented the IAFD bots, phase matching bot, and phase analysis bot. B.H.R. implemented the diagram rendering algorithm, and Analysis & Reporting and Visualizer & Interface bots. S.K. performed the comparison with NMFK. R.A.B. assisted with programming in several components of CRYSTAL. R.B.vD. and J.M.G. acquired Pd-Rh-Ta data, and S.K.S. and J.M.G. acquired Nb-Cu-V data with assistance as noted in the Acknowledgments. S.K.S. and J.M.G. served as human experts for both systems. C.P.G. and J.M.G. were the primary authors of the manuscript. S.A., J.Ba., J.Bj., C.P.G., J.G.M., B.H.R., and Y.X. were the primary authors of the Methods and Supplementary Information. \n\nData availability: The raw data for the Pd-Rh-Ta along with CRYSTAL's results and reports will be available at http://www.udiscover.it/resources/data/. Further documentation and source code for IAFD can be found at http://www.udiscover.it/resources/software/.", "abstract": "We introduce CRYSTAL, a multi-agent AI system for crystal-structure phase mapping. CRYSTAL is the first system that can automatically generate a portfolio of physically meaningful phase diagrams for expert-user exploration and selection. CRYSTAL outperforms previous methods to solve the example Pd-Rh-Ta phase diagram, enabling the discovery of a mixed-intermetallic methanol oxidation electrocatalyst. The integration of multiple data-knowledge sources and learning and reasoning algorithms, combined with the exploitation of problem decompositions, relaxations, and parallelism, empowers AI to supersede human scientific data interpretation capabilities and enable otherwise inaccessible scientific discovery in materials science and beyond.", "date": "2019-06", "date_type": "published", "publication": "MRS Communications", "volume": "9", "number": "2", "publisher": "Materials Research Society", "pagerange": "600-608", "id_number": "CaltechAUTHORS:20190816-090926308", "issn": "2159-6859", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190816-090926308", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CCF-1522054" }, { "agency": "NSF", "grant_number": "CNS-0832782" }, { "agency": "NSF", "grant_number": "CNS-1059284" }, { "agency": "NSF", "grant_number": "IIS-1344201" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-14-1-0498" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-17-1-0187" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0136" }, { "agency": "Toyota Research Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "NSF", "grant_number": "DMR-1332208" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1557/mrc.2019.50", "pub_year": "2019", "author_list": "Gomes, Carla P.; Bai, Junwen; et el." }, { "id": "https://authors.library.caltech.edu/records/86erg-1t536", "eprint_id": 94206, "eprint_status": "archive", "datestamp": "2023-08-22 01:41:30", "lastmod": "2023-10-20 17:46:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Mufan", "name": { "family": "Li", "given": "Mufan" }, "orcid": "0000-0002-4575-4055" }, { "id": "Duanmu-Kaining", "name": { "family": "Duanmu", "given": "Kaining" } }, { "id": "Wan-Chengzhang", "name": { "family": "Wan", "given": "Chengzhang" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Zhang-Liang", "name": { "family": "Zhang", "given": "Liang" }, "orcid": "0000-0003-3115-1752" }, { "id": "Dai-Sheng", "name": { "family": "Dai", "given": "Sheng" } }, { "id": "Chen-Wenxin", "name": { "family": "Chen", "given": "Wenxin" } }, { "id": "Zhao-Zipeng", "name": { "family": "Zhao", "given": "Zipeng" } }, { "id": "Li-Peng", "name": { "family": "Li", "given": "Peng" } }, { "id": "Fei-Huilong", "name": { "family": "Fei", "given": "Huilong" }, "orcid": "0000-0002-4216-5810" }, { "id": "Zhu-Yuanming", "name": { "family": "Zhu", "given": "Yuanming" } }, { "id": "Yu-Rong", "name": { "family": "Yu", "given": "Rong" }, "orcid": "0000-0003-1687-3597" }, { "id": "Luo-Jun", "name": { "family": "Luo", "given": "Jun" }, "orcid": "0000-0001-5084-2087" }, { "id": "Zang-Ketao", "name": { "family": "Zang", "given": "Ketao" } }, { "id": "Lin-Zhaoyang", "name": { "family": "Lin", "given": "Zhaoyang" }, "orcid": "0000-0002-6474-7184" }, { "id": "Ding-Mengning", "name": { "family": "Ding", "given": "Mengning" } }, { "id": "Huang-Jin", "name": { "family": "Huang", "given": "Jin" } }, { "id": "Sun-Hongtao", "name": { "family": "Sun", "given": "Hongtao" } }, { "id": "Guo-Jinghua", "name": { "family": "Guo", "given": "Jinghua" }, "orcid": "0000-0002-8576-2172" }, { "id": "Pan-Xiaoqing", "name": { "family": "Pan", "given": "Xiaoqing" }, "orcid": "0000-0002-0965-8568" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Sautet-P", "name": { "family": "Sautet", "given": "Philippe" }, "orcid": "0000-0002-8444-3348" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" } ] }, "title": "Single-atom tailoring of platinum nanocatalysts for high-performance multifunctional electrocatalysis", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrocatalysis; Energy; Heterogeneous catalysis", "note": "\u00a9 2019 Springer Nature Publishing AG. \n\nReceived 20 October 2018; Accepted 29 March 2019; Published\n20 May 2019. \n\nData availability: The data that support the findings of this study are available from the corresponding authors on reasonable request. \n\nY.H. acknowledges support from the Office of Naval Research (grant no. N000141812155). X.D. acknowledges financial support from the National Science Foundation (grant no. 1800580). T.C. was supported by the Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD) and the 111 Project. W.A.G. was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE\u2010SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation grant no. ACI\u20101053575. J.L. acknowledges the National Key R&D Program of China (2017YFA0700104) and National Natural Science Foundation of China (51761165012). STEM experiments were conducted using the facilities in the Irvine Materials Research Institute (IMRI) at the University of California-Irvine. The authors thank S. Fakra for technical support for the EXAFS experiment. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DEAC02-05CH11231. R.Y. acknowledges the National Natural Science Foundation of China (51525102, 51390475). Use of resources of the National Center for Electron Microscopy in Beijing is acknowledged. The calculations were performed on the Hoffman2 cluster at UCLA Institute for Digital Research and Education (IDRE) and the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by the National Science Foundation (grant no. ACI\u20101053575). \n\nAuthor Contributions: X.D., Y.H. and P.S. supervised the project and designed the research. X.D., Y.H. and M.L. conceived the idea. M.L. and C.W. performed the synthesis, electrochemical tests and characterizations. K.D. and P.S. conceived and performed the DFT calculations. T.C. and W.G. performed the model simulations. L.Z. and W.C. performed XAS measurements and analysis. J.G. and W.C. provided expertise for XAS analysis. S.D. and X.P. performed the EELS and HAADF-STEM measurements. Z.Z., Y.Z., R.Y., J.L., K.Z. and Z.L. assisted with material characterizations. Z.Z., P.L., H.F., M.D., J.H. and H.S. assisted with catalytic measurements. M.L., K.D., C.W., P.S., Y.H. and X.D. co-wrote the paper. All authors discussed the results and commented on the manuscript. \n\nThe authors declare no competing interests.\n\nSupplemental Material - 41929_2019_279_MOESM1_ESM.pdf
Supplemental Material - 41929_2019_279_MOESM2_ESM.txt
", "abstract": "Platinum-based nanocatalysts play a crucial role in various electrocatalytic systems that are important for renewable, clean energy conversion, storage and utilization. However, the scarcity and high cost of Pt seriously limit the practical application of these catalysts. Decorating Pt catalysts with other transition metals offers an effective pathway to tailor their catalytic properties, but often at the sacrifice of the electrochemical active surface area (ECSA). Here we report a single-atom tailoring strategy to boost the activity of Pt nanocatalysts with minimal loss in surface active sites. By starting with PtNi alloy nanowires and using a partial electrochemical dealloying approach, we create single-nickel-atom-modified Pt nanowires with an optimum combination of specific activity and ECSA for the hydrogen evolution, methanol oxidation and ethanol oxidation reactions. The single-atom tailoring approach offers an effective strategy to optimize the activity of surface Pt atoms and enhance the mass activity for diverse reactions, opening a general pathway to the design of highly efficient and durable precious metal-based catalysts.", "date": "2019-06", "date_type": "published", "publication": "Nature Catalysis", "volume": "2", "number": "6", "publisher": "Springer", "pagerange": "495-503", "id_number": "CaltechAUTHORS:20190327-094804466", "issn": "2520-1158", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190327-094804466", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141812155" }, { "agency": "NSF", "grant_number": "CHE-1800580" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD)" }, { "agency": "111 Project" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010SC0004993" }, { "agency": "NSF", "grant_number": "ACI\u20101053575" }, { "agency": "National Key R&D Program of China", "grant_number": "2017YFA0700104" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51761165012" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51525102" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51390475" }, { "agency": "NSF", "grant_number": "ACI\u20101053575" } ] }, "other_numbering_system": { "items": [ { "id": "1339", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41929-019-0279-6", "primary_object": { "basename": "41929_2019_279_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/86erg-1t536/files/41929_2019_279_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41929_2019_279_MOESM2_ESM.txt", "url": "https://authors.library.caltech.edu/records/86erg-1t536/files/41929_2019_279_MOESM2_ESM.txt" } ], "pub_year": "2019", "author_list": "Li, Mufan; Duanmu, Kaining; et el." }, { "id": "https://authors.library.caltech.edu/records/b9tj6-f4792", "eprint_id": 95774, "eprint_status": "archive", "datestamp": "2023-08-19 15:56:34", "lastmod": "2023-10-20 22:01:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yao-Yunxi", "name": { "family": "Yao", "given": "Yunxi" }, "orcid": "0000-0002-0814-6675" }, { "id": "Shushkov-Philip", "name": { "family": "Shushkov", "given": "Philip" }, "orcid": "0000-0002-6613-6117" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Giapis-K-P", "name": { "family": "Giapis", "given": "Konstantinos P." }, "orcid": "0000-0002-7393-298X" } ] }, "title": "Direct dioxygen evolution in collisions of carbon dioxide with surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 09 December 2018; Accepted 29 April 2019; Published 24 May 2019. \n\nData availability: All relevant raw data, experimental and computational, are available from the authors upon request. \n\nCode availability: The computational code is available from the authors upon request. \n\nThis report was based on work funded by NSF (Award no. 1202567) and by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award no. DE-SC0004993). P.S. is grateful for a postdoctoral fellowship funded by the Deutsche Forschungsgemeinschaft. \n\nAuthor Contributions: Y.Y. and K.P.G. designed the experiments. P.S. and T.F.M. designed the simulations. Y.Y. conducted experimental measurements, while P.S. performed the computations. All authors participated in analyzing the results and writing the paper. \n\nThe authors declare no competing interests.\n\nThe original version of this Article contained errors in Fig. 1. The titles at the top of each panel a, b, c were incorrectly given as 'CO2+/Au \u2192 CO2+ A', 'CO2+/Au \u2192 CO2+ B' and 'CO2+/Au \u2192 O2\u2013 C' instead of the correct panel a, b, c 'CO2+/Au \u2192 CO2+', 'CO2+/Au \u2192 O2+' and 'CO2+/Au \u2192 O2\u2013', respectively. This has been corrected in the PDF and HTML versions of the Article.\n\nPublished - s41467-019-10342-6.pdf
Supplemental Material - 41467_2019_10342_MOESM1_ESM.docx
Supplemental Material - 41467_2019_10342_MOESM2_ESM.pdf
Supplemental Material - 41467_2019_10342_MOESM3_ESM.docx
Supplemental Material - 41467_2019_10342_MOESM4_ESM.mpg
Erratum - s41467-019-10728-6.pdf
", "abstract": "The intramolecular conversion of CO_2 to molecular oxygen is an exotic reaction, rarely observed even with extreme optical or electronic excitation means. Here we show that this reaction occurs readily when CO_2 ions scatter from solid surfaces in a two-step sequential collision process at hyperthermal incidence energies. The produced O_2 is preferentially ionized by charge transfer from the surface over the predominant atomic oxygen product, leading to direct detection of both O_2+ and O_2\u2212. First-principles simulations of the collisional dynamics reveal that O_2 production proceeds via strongly-bent CO_2 configurations, without visiting other intermediates. Bent CO_2 provides dynamic access to the symmetric dissociation of CO_2 to C+O_2 with a calculated yield of 1 to 2% depending on molecular orientation. This unexpected collision-induced transformation of individual CO_2 molecules provides an accessible pathway for generating O_2 in astrophysical environments and may inspire plasma-driven electro- and photo-catalytic strategies for terrestrial CO_2 reduction.", "date": "2019-05-24", "date_type": "published", "publication": "Nature Communications", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2294", "id_number": "CaltechAUTHORS:20190524-082754901", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190524-082754901", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "PHY-1202567" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-019-10342-6", "pmcid": "PMC6534623", "primary_object": { "basename": "41467_2019_10342_MOESM4_ESM.mpg", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/41467_2019_10342_MOESM4_ESM.mpg" }, "related_objects": [ { "basename": "s41467-019-10342-6.pdf", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/s41467-019-10342-6.pdf" }, { "basename": "s41467-019-10728-6.pdf", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/s41467-019-10728-6.pdf" }, { "basename": "41467_2019_10342_MOESM1_ESM.docx", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/41467_2019_10342_MOESM1_ESM.docx" }, { "basename": "41467_2019_10342_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/41467_2019_10342_MOESM2_ESM.pdf" }, { "basename": "41467_2019_10342_MOESM3_ESM.docx", "url": "https://authors.library.caltech.edu/records/b9tj6-f4792/files/41467_2019_10342_MOESM3_ESM.docx" } ], "pub_year": "2019", "author_list": "Yao, Yunxi; Shushkov, Philip; et el." }, { "id": "https://authors.library.caltech.edu/records/drwp4-ykd49", "eprint_id": 95235, "eprint_status": "archive", "datestamp": "2023-08-19 15:48:26", "lastmod": "2023-10-20 19:01:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Buckley-Aya-K", "name": { "family": "Buckley", "given": "Aya K." } }, { "id": "Lee-Michelle-W", "name": { "family": "Lee", "given": "Michelle" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Kazantsev-Roman-V", "name": { "family": "Kazantsev", "given": "Roman V." } }, { "id": "Larson-David-M", "name": { "family": "Larson", "given": "David M." }, "orcid": "0000-0001-9634-9175" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Toste-F-Dean", "name": { "family": "Toste", "given": "F. Dean" }, "orcid": "0000-0001-8018-2198" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" } ] }, "title": "Electrocatalysis at Organic\u2013Metal Interfaces: Identification of Structure\u2013Reactivity Relationships for CO\u2082 Reduction at Modified Cu Surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: December 21, 2018; Published: March 31, 2019. \n\nThis material was based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We acknowledge Dr. Jason K. Cooper, Dr. Adam Z. Weber, Ms. Philomena Weng, Dr. Anna Wuttig, Dr. Drew Higgins, and Prof. Miquel Salmeron for fruitful discussions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b13655_si_001
Supplemental Material - ja8b13655_si_002.pdf
", "abstract": "The limited selectivity of existing CO\u2082 reduction catalysts and rising levels of CO\u2082 in the atmosphere necessitate the identification of specific structure\u2013reactivity relationships to inform catalyst development. Herein, we develop a predictive framework to tune the selectivity of CO_2 reduction on Cu by examining a series of polymeric and molecular modifiers. We find that protic species enhance selectivity for H\u2082, hydrophilic species enhance formic acid formation, and cationic hydrophobic species enhance CO selectivity. ReaxFF reactive molecular dynamics simulations indicate that the hydrophilic/hydrophobic modifiers influence the formation of surface hydrides, which yield formic acid or H\u2082. These observations offer insights into how these modifiers influence catalytic behavior at the non-precious Cu surface and may aid in the future implementation of organic structures in CO\u2082 reduction devices.", "date": "2019-05-08", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "18", "publisher": "American Chemical Society", "pagerange": "7355-7364", "id_number": "CaltechAUTHORS:20190506-093522029", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190506-093522029", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1335", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b13655", "primary_object": { "basename": "ja8b13655_si_001", "url": "https://authors.library.caltech.edu/records/drwp4-ykd49/files/ja8b13655_si_001" }, "related_objects": [ { "basename": "ja8b13655_si_002.pdf", "url": "https://authors.library.caltech.edu/records/drwp4-ykd49/files/ja8b13655_si_002.pdf" } ], "pub_year": "2019", "author_list": "Buckley, Aya K.; Lee, Michelle; et el." }, { "id": "https://authors.library.caltech.edu/records/v8qf2-nsk37", "eprint_id": 95415, "eprint_status": "archive", "datestamp": "2023-08-22 01:34:14", "lastmod": "2023-10-20 20:12:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Borgwardt-Mario", "name": { "family": "Borgwardt", "given": "Mario" }, "orcid": "0000-0002-1693-7047" }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Favaro-Marco", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Plate-Paul", "name": { "family": "Plate", "given": "Paul" } }, { "id": "H\u00f6hn-Christian", "name": { "family": "H\u00f6hn", "given": "Christian" }, "orcid": "0000-0002-2043-598X" }, { "id": "Abou-Ras-Daniel", "name": { "family": "Abou-Ras", "given": "Daniel" } }, { "id": "Schwarzburg-Klaus", "name": { "family": "Schwarzburg", "given": "Klaus" } }, { "id": "van-de-Krol-Roel", "name": { "family": "van de Krol", "given": "Roel" }, "orcid": "0000-0003-4399-399X" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Eichberger-Rainer", "name": { "family": "Eichberger", "given": "Rainer" }, "orcid": "0000-0001-9521-0024" }, { "id": "Friedrich-Dennis", "name": { "family": "Friedrich", "given": "Dennis" }, "orcid": "0000-0003-4844-368X" } ] }, "title": "Femtosecond time-resolved two-photon photoemission studies of ultrafast carrier relaxation in Cu_2O photoelectrodes", "ispublished": "pub", "full_text_status": "public", "keywords": "Chemical physics; Energy; Photocatalysis", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 09 November 2018; Accepted 23 April 2019; Published\n08 May 2019. \n\nData availability: The source data underlying Figs. 2a\u2013d and 3 are available in Zenodo, https://doi.org/10.5281/zenodo.2628238. The source data for the Supplementary Figures are available from the corresponding author upon reasonable request. \n\nM.B., R.E. and D.F. thank P. Sippel for discussions. M.B. acknowledges funding from the Helmholtz Association through the Excellence network UniSysCat (ExNet-0024-1). This work was supported in part (S.T.O., H.A.A. and N.S.L.) through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. D.F. acknowledges support by the German Research Foundation (DFG), project numbers PAK 981/1 and FR 4025/2-1. \n\nAuthor Contributions: M.B., D.F. and R.E. designed the experiments on samples provided by S.T.O, H.A.A., and N.S.L. M.B. and D.F. carried out the laser experiments and analyzed the data with the help of R. vdK and R.E. M.B., M.F., P.P., C.H. and D.F. performed the LEED and XPS measurements and analyzed the data. D.A.-R. performed the SEM/EDX experiments. K.S. performed the AFM measurements. M.B., R.E. and D.F. prepared the paper. All authors discussed the results and commented on the paper. \n\nThe authors declare no competing interests.\n\nPublished - s41467-019-10143-x.pdf
Supplemental Material - 41467_2019_10143_MOESM1_ESM.pdf
Supplemental Material - 41467_2019_10143_MOESM2_ESM.pdf
", "abstract": "Cuprous oxide (Cu_2O) is a promising material for solar-driven water splitting to produce hydrogen. However, the relatively small accessible photovoltage limits the development of efficient Cu_2O based photocathodes. Here, femtosecond time-resolved two-photon photoemission spectroscopy has been used to probe the electronic structure and dynamics of photoexcited charge carriers at the Cu_2O surface as well as the interface between Cu_2O and a platinum (Pt) adlayer. By referencing ultrafast energy-resolved surface sensitive spectroscopy to bulk data we identify the full bulk to surface transport dynamics for excited electrons rapidly localized within an intrinsic deep continuous defect band ranging from the whole crystal volume to the surface. No evidence of bulk electrons reaching the surface at the conduction band level is found resulting into a substantial loss of their energy through ultrafast trapping. Our results uncover main factors limiting the energy conversion processes in Cu_2O and provide guidance for future material development.", "date": "2019-05-08", "date_type": "published", "publication": "Nature Communications", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2106", "id_number": "CaltechAUTHORS:20190513-072232965", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190513-072232965", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Helmholtz Association", "grant_number": "ExNet-0029-1" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "PAK 981/1" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "FR 4025/2-1" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1038/s41467-019-10143-x", "pmcid": "PMC6506537", "primary_object": { "basename": "41467_2019_10143_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/v8qf2-nsk37/files/41467_2019_10143_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2019_10143_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/v8qf2-nsk37/files/41467_2019_10143_MOESM2_ESM.pdf" }, { "basename": "s41467-019-10143-x.pdf", "url": "https://authors.library.caltech.edu/records/v8qf2-nsk37/files/s41467-019-10143-x.pdf" } ], "pub_year": "2019", "author_list": "Borgwardt, Mario; Omelchenko, Stefan T.; et el." }, { "id": "https://authors.library.caltech.edu/records/9thsy-ap890", "eprint_id": 94450, "eprint_status": "archive", "datestamp": "2023-08-22 01:32:30", "lastmod": "2023-10-20 17:58:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Qian-Jin", "name": { "family": "Qian", "given": "Jin" }, "orcid": "0000-0002-0162-0477" }, { "id": "Ye-Yifan", "name": { "family": "Ye", "given": "Yifan" } }, { "id": "Yang-Hao", "name": { "family": "Yang", "given": "Hao" }, "orcid": "0000-0002-8241-6231" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Initial steps in forming the electrode electrolyte interface: H_2O adsorption and complex formation on the Ag(111) surface from combining Quantum Mechanics calculations and X-ray Photoelectron Spectroscopy", "ispublished": "pub", "full_text_status": "public", "keywords": "Density Functional Theory (DFT); PBE-D3; ambient pressure XPS; Chemical Reaction Network (CRN)", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: December 21, 2018; Published: April 4, 2019. \n\nWe thank Yufeng Huang and Samuel Clamons for helpful discussions. This project was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. W.A.G. was supported by the Computational Materials Sciences Program funded by the U.S. Department of Energy, Office of Science, Basic Energy Sciences, under Award No. DE-SC00014607. The calculations were carried out on the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant No. ACI-1548562. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. In addition, Y.Y. and E.J.C. were partially supported by an Early Career Award in the Condensed Phase and Interfacial Molecular Science Program, in the Chemical Sciences Geosciences and Biosciences Division of the Office of Basic Energy Sciences of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nAuthor Contributions: J.Q. and Y.Y. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b13672_si_001.txt
Supplemental Material - ja8b13672_si_002.pdf
", "abstract": "The interaction of water with metal surfaces is at the heart of electrocatalysis. But there remain enormous uncertainties about the atomistic interactions at the electrode\u2013electrolyte interface (EEI). As the first step toward an understanding of the EEI, we report here the details of the initial steps of H_2O adsorption and complex formation on a Ag(111) surface, based on coupling quantum mechanics (QM) and ambient-pressure X-ray photoelectron spectroscopy (APXPS) experiments. We find a close and direct comparison between simulation and experiment, validated under various isotherm and isobar conditions. We identify five observable oxygen-containing species whose concentrations depend sensitively on temperature and pressure: chemisorbed O* and OH*, H_2O* stabilized by hydrogen bond interactions with OH* or O*, and multilayer H_2O*. We identify the species experimentally by their O 1s core-level shift that we calculate with QM along with the structures and free energies as a function of temperature and pressure. This leads to a chemical reaction network (CRN) that we use to predict the time evolution of their concentrations over a wide range of temperature (298\u2013798 K) and pressure conditions (10^(\u20136)\u20131 Torr), which agree well with the populations determined from APXPS. This multistep simulation CRN protocol should be useful for other heterogeneous catalytic systems.", "date": "2019-05-01", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "141", "number": "17", "publisher": "American Chemical Society", "pagerange": "6946-6954", "id_number": "CaltechAUTHORS:20190404-092810356", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190404-092810356", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1330", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b13672", "primary_object": { "basename": "ja8b13672_si_001.txt", "url": "https://authors.library.caltech.edu/records/9thsy-ap890/files/ja8b13672_si_001.txt" }, "related_objects": [ { "basename": "ja8b13672_si_002.pdf", "url": "https://authors.library.caltech.edu/records/9thsy-ap890/files/ja8b13672_si_002.pdf" } ], "pub_year": "2019", "author_list": "Qian, Jin; Ye, Yifan; et el." }, { "id": "https://authors.library.caltech.edu/records/2wn4r-x6258", "eprint_id": 94977, "eprint_status": "archive", "datestamp": "2023-08-19 15:31:35", "lastmod": "2023-10-20 18:27:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Hongyan", "name": { "family": "Jiang", "given": "Hongyan" } }, { "id": "Kammler-M", "name": { "family": "Kammler", "given": "Marvin" } }, { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Dorenkamp-Y", "name": { "family": "Dorenkamp", "given": "Yvonne" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Wodtke-A-M", "name": { "family": "Wodtke", "given": "Alec. M." } }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Kandratsenka-A", "name": { "family": "Kandratsenka", "given": "Alexander" } }, { "id": "B\u00fcnermann-O", "name": { "family": "B\u00fcnermann", "given": "Oliver" } } ] }, "title": "Imaging covalent bond formation by H atom scattering from graphene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Association for the Advancement of Science. \n\nReceived 16 January 2019; accepted 6 March 2019. \n\nWe thank D. Auerbach and D. Schwarzer for helpful discussions. Funding: H.J., O.B., and A.M.W. acknowledge support the from the SFB1073 under project A04, from the Deutsche Forschungsgemeinschaft (DFG) and financial support from the Ministerium f\u00fcr Wissenschaft und Kultur (MWK) Niedersachsen, and the Volkswagenstiftung under grant INST 186/902-1 to build the experimental apparatus. A.M.W., M.K., and A.K. also acknowledge the Max Planck Society for the Advancement of Science. F.D. and T.F.M. acknowledge that this material is based on work performed by the Joint Center for Artificial Photosynthesis, a U.S. Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under award DE-SC0004993. T.F.M. and F.R.M. acknowledge joint support from the DOE (award DE-SC0019390). F.R.M. is grateful to the Engineering and Physical Sciences Research Council for funding (EP/M013111/1). \n\nAuthor contributions: H.J. carried out experiments, analyzed experimental data and contributed to the manuscript. M.K. participated in the MD and RPMD code development, fit the EMFT data to a REBO potential, carried out molecular dynamics calculations, and contributed to the manuscript. Y.D. assisted with experiments. F.D. contributed to the EMFT code, carried out the EMFT calculations, and contributed to the manuscript. F.R.M. contributed to the EMFT code. A.K. directed the molecular dynamics work, developed the MD code, and contributed to the manuscript. A.M.W. conceived the experiment and wrote the paper. T.F.M. directed the electronic structure work, contributed to the EMFT code, and contributed to the manuscript. O.B. built and commissioned the Rydberg tagging apparatus, conceived and supervised experimentation, and contributed to the manuscript. \n\nCompeting interests: None declared. \n\nData and materials availability: The PES is archived at github.com/akandra/md_tian2/blob/master/src/pes_rebo_mod.f90. There are no restrictions on materials used in this work. All data needed to evaluate the conclusions in the paper are present in the paper or the supplementary materials.\n\nSupplemental Material - aaw6378-Jiang-SM.pdf
Supplemental Material - aaw6378s1.mov
", "abstract": "Viewing the atomic-scale motion and energy dissipation pathways involved in forming a covalent bond is a longstanding challenge for chemistry. We performed scattering experiments of H atoms from graphene and observed a bimodal translational energy loss distribution. Using accurate first-principles dynamics simulations, we show that the quasi-elastic channel involves scattering through the physisorption well where collision sites are near the centers of the six-membered C-rings. The second channel results from transient C\u2013H bond formation, where H atoms lose 1 to 2 electron volts of energy within a 10-femtosecond interaction time. This remarkably rapid form of intramolecular vibrational relaxation results from the C atom's rehybridization during bond formation and is responsible for an unexpectedly high sticking probability of H on graphene.", "date": "2019-04-26", "date_type": "published", "publication": "Science", "volume": "364", "number": "6438", "publisher": "American Association for the Advancement of Science", "pagerange": "379-382", "id_number": "CaltechAUTHORS:20190425-132430583", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190425-132430583", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "SFB1073" }, { "agency": "Ministerium f\u00fcr Wissenschaft und Kultur (MWK)" }, { "agency": "Volkswagenstiftung", "grant_number": "INST 186/902-1" }, { "agency": "Max Planck Society" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0019390" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1126/science.aaw6378", "primary_object": { "basename": "aaw6378-Jiang-SM.pdf", "url": "https://authors.library.caltech.edu/records/2wn4r-x6258/files/aaw6378-Jiang-SM.pdf" }, "related_objects": [ { "basename": "aaw6378s1.mov", "url": "https://authors.library.caltech.edu/records/2wn4r-x6258/files/aaw6378s1.mov" } ], "pub_year": "2019", "author_list": "Jiang, Hongyan; Kammler, Marvin; et el." }, { "id": "https://authors.library.caltech.edu/records/k0nj4-1aq37", "eprint_id": 94892, "eprint_status": "archive", "datestamp": "2023-08-19 15:29:32", "lastmod": "2023-10-20 18:22:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ye-Yifan", "name": { "family": "Ye", "given": "Yifan" } }, { "id": "Yang-Hao", "name": { "family": "Yang", "given": "Hao" }, "orcid": "0000-0002-8241-6231" }, { "id": "Qian-Jin", "name": { "family": "Qian", "given": "Jin" }, "orcid": "0000-0002-0162-0477" }, { "id": "Su-Hongyang", "name": { "family": "Su", "given": "Hongyang" } }, { "id": "Lee-Kyung-Jae", "name": { "family": "Lee", "given": "Kyung-Jae" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" } ] }, "title": "Dramatic differences in carbon dioxide adsorption and initial steps of reduction between silver and copper", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2019. Open Access - This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 25 August 2018. Accepted 27 March 2019. Published 23 April 2019. \n\nThis work was supported through the Office of Science, Office of Basic Energy Science (BES), of the US Department of Energy (DOE) under Award DE-SC0004993 to the Joint Center for Artificial Photosynthesis, DOE Energy Innovation Hubs. The Advanced Light Source is supported by the Director, Office of Science, Office of BES, of the US DOE under Contract DE-AC02-05CH11231. H.Y. and H.S. gratefully acknowledge China Scholarship Council (CSC, No. 201608320161 and No. 201706340112) for financial support. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. Y.Y. and E.J.C. were partially supported by an Early Career Award in the Condensed Phase and Interfacial Molecular Science Program, in the Chemical Sciences Geosciences and Biosciences Division of the Office of Basic Energy Sciences of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThese authors contributed equally: Yifan Ye, Hao Yang, Jin Qian. \n\nAuthor Contributions: Y.Y., J.Y., W.A.G. III and E.J.C. designed the experiments. Y.Y., H.S., K.J.L. and E.J.C. performed the APXPS experiments. H.Y., J.Q., T.C. and H.X. conducted the theoretical computations. Y.Y., H.Y., J.Q., J.Y., W.A.G. III and E.J.C. analyzed the data and wrote the manuscript. All authors contributed to the overall scientific interpretation and edited the manuscript. \n\nData availability: The data that support the findings of this study are available from the corresponding authors upon request. \n\nThe authors declare no competing interests. \n\nJournal peer review information: Nature communication would like to thank Aravind Asthagiri and other anonymous reviewers for their contribution to the peer review of this work. Peer review reports are available.\n\nPublished - 41467_2019_9846_MOESM2_ESM.pdf
Published - s41467-019-09846-y.pdf
Supplemental Material - 41467_2019_9846_MOESM1_ESM.pdf
", "abstract": "Converting carbon dioxide (CO_2) into liquid fuels and synthesis gas is a world-wide priority. But there is no experimental information on the initial atomic level events for CO_2 electroreduction on the metal catalysts to provide the basis for developing improved catalysts. Here we combine ambient pressure X-ray photoelectron spectroscopy with quantum mechanics to examine the processes as Ag is exposed to CO_2 both alone and in the presence of H_2O at 298\u2009K. We find that CO_2 reacts with surface O on Ag to form a chemisorbed species (O\u2009=\u2009CO_2^(\u03b4\u2212)). Adding H_2O and CO_2 then leads to up to four water attaching on O\u2009=\u2009CO_2^(\u03b4\u2212) and two water attaching on chemisorbed (b-)CO_2. On Ag we find a much more favorable mechanism involving the O\u2009=\u2009CO_2^(\u03b4\u2212) compared to that involving b-CO_2 on Cu. Each metal surface modifies the gas-catalyst interactions, providing a basis for tuning CO_2 adsorption behavior to facilitate selective product formations.", "date": "2019-04-23", "date_type": "published", "publication": "Nature Communications", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 1875", "id_number": "CaltechAUTHORS:20190423-101937653", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190423-101937653", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "China Scholarship Council", "grant_number": "201608320161" }, { "agency": "China Scholarship Council", "grant_number": "201706340112" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1333", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-019-09846-y", "pmcid": "PMC6478877", "primary_object": { "basename": "41467_2019_9846_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/k0nj4-1aq37/files/41467_2019_9846_MOESM2_ESM.pdf" }, "related_objects": [ { "basename": "s41467-019-09846-y.pdf", "url": "https://authors.library.caltech.edu/records/k0nj4-1aq37/files/s41467-019-09846-y.pdf" }, { "basename": "41467_2019_9846_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/k0nj4-1aq37/files/41467_2019_9846_MOESM1_ESM.pdf" } ], "pub_year": "2019", "author_list": "Ye, Yifan; Yang, Hao; et el." }, { "id": "https://authors.library.caltech.edu/records/ttsp8-k4150", "eprint_id": 93786, "eprint_status": "archive", "datestamp": "2023-08-22 01:24:29", "lastmod": "2023-10-20 17:25:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Fortunelli-Alessandro", "name": { "family": "Fortunelli", "given": "Alessandro" }, "orcid": "0000-0001-5337-4450" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Reaction intermediates during operando electrocatalysis identified from full solvent quantum mechanics molecular dynamics", "ispublished": "pub", "full_text_status": "public", "keywords": "quantum mechanics; molecular dynamics; vibration mode; CO_2 reduction reaction; reaction mechanism", "note": "\u00a9 2019 National Academy of Sciences. Published under the PNAS license. \n\nContributed by William A. Goddard III, January 28, 2019 (sent for review December 20, 2018; reviewed by Sharon Hammes-Schiffer, Philippe Sautet, and Richard J. Saykally). PNAS published ahead of print March 13, 2019. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. These studies used the Extreme Science and Engineering Discovery Environment which is supported by National Science Foundation Grant ACI-1053575. This work is supported by Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions (PAPD), the 111 Project. \n\nAuthor contributions: T.C. and W.A.G. designed research; T.C. and A.F. performed research; T.C. and W.A.G. analyzed data; and T.C., A.F., and W.A.G. wrote the paper. \n\nReviewers: S.H.-S., Yale University; P.S., University of California, Los Angeles; and R.J.S., University of California, Berkeley. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1821709116/-/DCSupplemental.\n\nPublished - 7718.full.pdf
Supplemental Material - pnas.1821709116.sapp.pdf
", "abstract": "Electrocatalysis provides a powerful means to selectively transform molecules, but a serious impediment in making rapid progress is the lack of a molecular-based understanding of the reactive mechanisms or intermediates at the electrode\u2013electrolyte interface (EEI). Recent experimental techniques have been developed for operando identification of reaction intermediates using surface infrared (IR) and Raman spectroscopy. However, large noises in the experimental spectrum pose great challenges in resolving the atomistic structures of reactive intermediates. To provide an interpretation of these experimental studies and target for additional studies, we report the results from quantum mechanics molecular dynamics (QM-MD) with explicit consideration of solvent, electrode\u2013electrolyte interface, and applied potential at 298 K, which conceptually resemble the operando experimental condition, leading to a prototype of operando QM-MD (o-QM-MD). With o-QM-MD, we characterize 22 possible reactive intermediates in carbon dioxide reduction reactions (CO_2 RRs). Furthermore, we report the vibrational density of states (v-DoSs) of these intermediates from two-phase thermodynamic (2PT) analysis. Accordingly, we identify important intermediates such as chemisorbed CO_2 (b-CO_2), *HOC-COH, *C-CH, and *C-COH in our o-QM-MD likely to explain the experimental spectrum. Indeed, we assign the experimental peak at 1,191 cm^(\u22121) to the mode of C-O stretch in *HOC-COH predicted at 1,189 cm^(\u22121) and the experimental peak at 1,584 cm^(\u22121) to the mode of C-C stretch in *C-COD predicted at 1,581 cm^(\u22121). Interestingly, we find that surface ketene (*C=C=O), arising from *HOC-COH dehydration, also shows signals at around 1,584 cm^(\u22121), which indicates a nonelectrochemical pathway of hydrocarbon formation at low overpotential and high pH conditions.", "date": "2019-04-16", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "116", "number": "16", "publisher": "National Academy of Sciences", "pagerange": "7718-7722", "id_number": "CaltechAUTHORS:20190313-133027865", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190313-133027865", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Jiangsu Higher Education Institutions" }, { "agency": "111 Project of China" } ] }, "other_numbering_system": { "items": [ { "id": "1327", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1821709116", "pmcid": "PMC6475413", "primary_object": { "basename": "pnas.1821709116.sapp.pdf", "url": "https://authors.library.caltech.edu/records/ttsp8-k4150/files/pnas.1821709116.sapp.pdf" }, "related_objects": [ { "basename": "7718.full.pdf", "url": "https://authors.library.caltech.edu/records/ttsp8-k4150/files/7718.full.pdf" } ], "pub_year": "2019", "author_list": "Cheng, Tao; Fortunelli, Alessandro; et el." }, { "id": "https://authors.library.caltech.edu/records/0raf9-cy352", "eprint_id": 94034, "eprint_status": "archive", "datestamp": "2023-08-19 15:24:28", "lastmod": "2023-10-20 17:37:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ho-Alec", "name": { "family": "Ho", "given": "Alec" } }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Sullivan-Ian", "name": { "family": "Sullivan", "given": "Ian" }, "orcid": "0000-0003-0632-4607" }, { "id": "Karp-C-L", "name": { "family": "Karp", "given": "Christoph" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Decoupling H_2(g) and O_2(g) Production in Water Splitting by a Solar-Driven V^(3+/2)+(aq,H_2SO_4)|KOH(aq) Cell", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Chemical Society. \n\nReceived: February 4, 2019; Accepted: March 21, 2019; Published: March 21, 2019. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, as well as the Gordon and Betty Moore Foundation. The authors thank Caltech's SURF Board for a Summer Undergraduate Research Fellowship and acknowledge Caltech's Federal Work-Study program. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz9b00278_si_001.pdf
", "abstract": "A solar-driven V^(3+/2+)(aq,H_2SO_4)|KOH(aq) cell, consisting of a carbon-cloth cathode in 2.0 M H_2SO_4(aq) with 0.36 M V_2(SO_4)_3 (pH \u22120.16), a Ni mesh anode in 2.5 M KOH(aq) (pH 14.21) for the oxygen-evolution reaction (OER), and a bipolar membrane that sustained the pH differentials between the catholyte and anolyte, enabled water splitting with spatial and temporal decoupling of the hydrogen evolution reaction (HER) from the OER and produced H_2(g) locally under pressure upon demand. Over a range of potentials and charging depths, V^(3+) was selectively reduced with >99.8% faradic efficiency. The V^(2+) species produced in the catholyte was then passed subsequently on demand over a MoCx-based HER catalyst to produce H_2(g) and regenerate V^(3+) for subsequent reduction. Under a base hydrogen pressure of 1, 10, and 100 atm, the discharge efficiency of the V^(3+) to hydrogen was 83%, 65.2%, and 59.8%, respectively. In conjunction with a solar tracker and a photovoltaic device, the V^(3+/2+)(aq,H_2SO_4)|KOH(aq) cell was charged outdoors under sunlight and discharged at night with a daily averaged diurnal solar-to-hydrogen (STH) energy conversion efficiency of 3.7% and a STH conversion efficiency of 5.8% during daylight operation.", "date": "2019-04-12", "date_type": "published", "publication": "ACS Energy Letters", "volume": "4", "number": "4", "publisher": "American Chemical Society", "pagerange": "968-976", "id_number": "CaltechAUTHORS:20190321-152633678", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190321-152633678", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acsenergylett.9b00278", "primary_object": { "basename": "nz9b00278_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0raf9-cy352/files/nz9b00278_si_001.pdf" }, "pub_year": "2019", "author_list": "Ho, Alec; Zhou, Xinghao; et el." }, { "id": "https://authors.library.caltech.edu/records/09h6b-rfv12", "eprint_id": 93864, "eprint_status": "archive", "datestamp": "2023-08-19 15:17:53", "lastmod": "2023-10-20 17:28:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Crystalline nickel, cobalt, and manganese antimonates as electrocatalysts for the chlorine evolution reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Royal Society of Chemistry. \n\nReceived 19th December 2018, Accepted 7th March 2019, First published on 12th March 2019. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. I. A. M.-H. acknowledges a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. We thank Dr K. Papadantonakis for assistance with editing the manuscript, and C. Finke for assistance with iodometric measurements. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c8ee03676d1_si.pdf
", "abstract": "The chlorine-evolution reaction (CER) is a common, commercially valuable electrochemical reaction, and is practiced at industrial scale globally. A precious metal solid solution of RuO_2 or IrO_2 with TiO_2 is the predominant electrocatalyst for the CER. Herein we report that materials comprised only of non-precious metal elements, specifically crystalline transition-metal antimonates (TMAs) such as NiSb_2O_x, CoSb_2O_x, and MnSb_2O_x, are moderately active, stable catalysts for the electrochemical oxidation of chloride to chlorine under conditions relevant to the commercial chlor-alkali process. Specifically, CoSb2Ox exhibited a galvanostatic potential of 1.804 V vs. NHE at 100 mA cm^(\u22122) of Cl_2(g) production from aqueous pH = 2.0, 4.0 M NaCl after 250 h of operation. Studies of the bulk and surface of the electrocatalyst and the composition of the electrolyte before and after electrolysis indicated minimal changes in the surface structure and intrinsic activity of CoSb_2O_x as a result of Cl2(g) evolution under these conditions.", "date": "2019-04-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "12", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "1241-1248", "id_number": "CaltechAUTHORS:20190315-102720320", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190315-102720320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/c8ee03676d", "primary_object": { "basename": "c8ee03676d1_si.pdf", "url": "https://authors.library.caltech.edu/records/09h6b-rfv12/files/c8ee03676d1_si.pdf" }, "pub_year": "2019", "author_list": "Moreno-Hernandez, Ivan A.; Brunschwig, Bruce S.; et el." }, { "id": "https://authors.library.caltech.edu/records/sb5em-fj996", "eprint_id": 94207, "eprint_status": "archive", "datestamp": "2023-08-22 01:12:39", "lastmod": "2023-10-20 17:46:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Soedarmadji-Edwin", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Synthesis, optical imaging, and absorption spectroscopy data for 179072 metal oxides", "ispublished": "pub", "full_text_status": "public", "keywords": "Imaging techniques; Photocatalysis", "note": "\u00a9 The Author(s) 2019. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 09 October 2018; Accepted 11 February 2019; Published 27 March 2019; Issue Date 01 December 2019. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). We thank Kevin Kan for processing materials libraries. \n\nAuthor Contributions: H.S.S. and J.M.G. conceived the project and wrote the majority of code and manuscript. E.S. maintained the database backend and generated composition information. P.F.N. synthesized libraries and collected spectra. D.G. curated processing information and helped in generating the h5 container. J.M.G. supervised the research project. \n\nCode Availability: Custom code for handling the dataset is available at https://github.com/helgestein/materials-images-spectra/. This python code enables users to easily download the dataset, pull specific or random images and accompanying spectra as well as processing and composition data. The code is intended to enable easy exploration of the dataset and to provide templates for use in machine learning models. The code requires python version 3.6.4 or higher with the following packages: h5py >\u2009=\u20092.7.1, numpy\u2009>\u2009\u2009=\u20091.15.2, tqdm\u2009>\u2009\u2009=\u20094.23.0. \n\nThe authors declare no competing interests.\n\nPublished - s41597-019-0019-4.pdf
Supplemental Material - 41597_2019_19_MOESM1_ESM.zip
", "abstract": "Optical absorption spectroscopy is an important materials characterization for applications such as solar energy generation. This data descriptor describes the to date (Dec 2018) largest publicly available curated materials science dataset for near infrared to near UV (UV-Vis) light absorbance, composition and processing properties of metal oxides. By supplying the complete synthesis and processing history of each of the 179072 samples from 99965 unique compositions we believe the dataset will enable the community to develop predictive models for materials, such as prediction of optical properties based on composition and processing, and ultimately serve as a benchmark dataset for continued integration of machine learning in materials science. The dataset is also a resource for identifying materials composition and synthesis to attain specific optical properties.", "date": "2019-03-27", "date_type": "published", "publication": "Scientific Data", "volume": "6", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 9", "id_number": "CaltechAUTHORS:20190327-100527853", "issn": "2052-4463", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190327-100527853", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41597-019-0019-4", "pmcid": "PMC6437643", "primary_object": { "basename": "41597_2019_19_MOESM1_ESM.zip", "url": "https://authors.library.caltech.edu/records/sb5em-fj996/files/41597_2019_19_MOESM1_ESM.zip" }, "related_objects": [ { "basename": "s41597-019-0019-4.pdf", "url": "https://authors.library.caltech.edu/records/sb5em-fj996/files/s41597-019-0019-4.pdf" } ], "pub_year": "2019", "author_list": "Stein, Helge S.; Soedarmadji, Edwin; et el." }, { "id": "https://authors.library.caltech.edu/records/kzs0z-4vr48", "eprint_id": 93644, "eprint_status": "archive", "datestamp": "2023-08-19 14:47:35", "lastmod": "2023-10-20 17:18:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Boyd-D-A", "name": { "family": "Boyd", "given": "David A." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Analyzing machine learning models to accelerate generation of fundamental materials insights", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Author(s). Open Access - This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 22 October 2018. Accepted 06 February 2019. Published 08 March 2019. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Development of the algorithm for automating the model interpretation (J.M.G. and H.S.S.) was funded by Toyota Research Institute through the Accelerated Materials Design and Discovery program. \n\nAuthor Contributions: M.U. performed model training and gradient analysis. H.S.S. and D.G. assisted with design of the model and comparisons to other techniques. P.F.N., D.G. and D.A.B. performed all experiments. M.U., H.S.S., D.G. and J.M.G. interpreted model outputs and created data visualization schemes. J.M.G. created algorithm for automated relationship identification with assistance from M.U. and H.S.S. M.U., H.S.S. and J.M.G. were the primary authors of the manuscript. \n\nCode availability: The authors declare that the code used to perform the analysis is provided at https://github.com/johnmgregoire/CNN_Gradient_Analysis. \n\nThe authors declare no competing interests.\n\nPublished - s41524-019-0172-5.pdf
Supplemental Material - 41524_2019_172_MOESM1_ESM.pdf
Supplemental Material - 41524_2019_172_MOESM2_ESM.csv
", "abstract": "Machine learning for materials science envisions the acceleration of basic science research through automated identification of key data relationships to augment human interpretation and gain scientific understanding. A primary role of scientists is extraction of fundamental knowledge from data, and we demonstrate that this extraction can be accelerated using neural networks via analysis of the trained data model itself rather than its application as a prediction tool. Convolutional neural networks excel at modeling complex data relationships in multi-dimensional parameter spaces, such as that mapped by a combinatorial materials science experiment. Measuring a performance metric in a given materials space provides direct information about (locally) optimal materials but not the underlying materials science that gives rise to the variation in performance. By building a model that predicts performance (in this case photoelectrochemical power generation of a solar fuels photoanode) from materials parameters (in this case composition and Raman signal), subsequent analysis of gradients in the trained model reveals key data relationships that are not readily identified by human inspection or traditional statistical analyses. Human interpretation of these key relationships produces the desired fundamental understanding, demonstrating a framework in which machine learning accelerates data interpretation by leveraging the expertize of the human scientist. We also demonstrate the use of neural network gradient analysis to automate prediction of the directions in parameter space, such as the addition of specific alloying elements, that may increase performance by moving beyond the confines of existing data.", "date": "2019-03-08", "date_type": "published", "publication": "npj Computational Materials", "volume": "5", "publisher": "Springer Nature", "pagerange": "Art. No. 34", "id_number": "CaltechAUTHORS:20190308-084331413", "issn": "2057-3960", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190308-084331413", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Toyota Research Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41524-019-0172-5", "primary_object": { "basename": "s41524-019-0172-5.pdf", "url": "https://authors.library.caltech.edu/records/kzs0z-4vr48/files/s41524-019-0172-5.pdf" }, "related_objects": [ { "basename": "41524_2019_172_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/kzs0z-4vr48/files/41524_2019_172_MOESM1_ESM.pdf" }, { "basename": "41524_2019_172_MOESM2_ESM.csv", "url": "https://authors.library.caltech.edu/records/kzs0z-4vr48/files/41524_2019_172_MOESM2_ESM.csv" } ], "pub_year": "2019", "author_list": "Umehara, Mitsutaro; Stein, Helge S.; et el." }, { "id": "https://authors.library.caltech.edu/records/17q43-5a321", "eprint_id": 91956, "eprint_status": "archive", "datestamp": "2023-09-21 20:53:48", "lastmod": "2023-10-23 23:21:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Choi-Chungseok", "name": { "family": "Choi", "given": "Chungseok" }, "orcid": "0000-0001-9169-1393" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Flores-Espinosa-M", "name": { "family": "Flores Espinosa", "given": "Michelle" }, "orcid": "0000-0002-5697-1290" }, { "id": "Fei-Huilong", "name": { "family": "Fei", "given": "Huilong" }, "orcid": "0000-0002-4216-5810" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" } ] }, "title": "A Highly Active Star Decahedron Cu Nanocatalyst for Hydrocarbon Production at Low Overpotentials", "ispublished": "pub", "full_text_status": "public", "keywords": "Cu nanoparticles, DFT, electrochemical CO_2 reduction, stacking faults, twin boundary", "note": "\u00a9 2018 WILEY\u2010VCH. \n\nReceived: August 18, 2018. Revised: November 16, 2018. Published online: December 14, 2018. Issue Online: 08 February 2019. \n\nTEM work was conducted using the facilities in the electron imaging center of at California NanoSystems Institute at the University of California Los Angles. C.C. and Y.H. acknowledge support by the Office of Naval Research (ONR) under grant number N000141712608. T.C. and W.A.G. were supported by Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE\u2010SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation grant number ACI\u20101053575. \n\nThe authors declare no conflict of interest.\n\nSupplemental Material - downloadSupplement_doi=10.1002_2Fadma.201805405_file=adma201805405-sup-0001-S1.pdf
", "abstract": "The electrochemical carbon dioxide reduction reaction (CO_2RR) presents a viable approach to recycle CO_2 gas into low carbon fuels. Thus, the development of highly active catalysts at low overpotential is desired for this reaction. Herein, a high\u2010yield synthesis of unique star decahedron Cu nanoparticles (SD\u2010Cu NPs) electrocatalysts, displaying twin boundaries (TBs) and multiple stacking faults, which lead to low overpotentials for methane (CH_4) and high efficiency for ethylene (C_2H_4) production, is reported. Particularly, SD\u2010Cu NPs show an onset potential for CH_4 production lower by 0.149 V than commercial Cu NPs. More impressively, SD\u2010Cu NPs demonstrate a faradaic efficiency of 52.43% \u00b1 2.72% for C_2H_4 production at \u22120.993 \u00b1 0.0129 V. The results demonstrate that the surface stacking faults and twin defects increase CO binding energy, leading to the enhanced CO_2RR performance on SD\u2010Cu NPs.", "date": "2019-02-08", "date_type": "published", "publication": "Advanced Materials", "volume": "31", "number": "6", "publisher": "Wiley", "pagerange": "Art. No. 1805405", "id_number": "CaltechAUTHORS:20181221-105357220", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181221-105357220", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Office of Naval Research (ONR)", "grant_number": "N000141712608" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010SC0004993" }, { "agency": "NSF", "grant_number": "ACI\u20101053575" } ] }, "other_numbering_system": { "items": [ { "id": "1317", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/adma.201805405", "primary_object": { "basename": "10.1002:adma.201805405-S1.pdf", "url": "https://authors.library.caltech.edu/records/17q43-5a321/files/10.1002:adma.201805405-S1.pdf" }, "pub_year": "2019", "author_list": "Choi, Chungseok; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/3d7kb-qhe12", "eprint_id": 92471, "eprint_status": "archive", "datestamp": "2023-08-22 00:54:21", "lastmod": "2023-10-20 15:44:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-Saber", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Liquid water is a dynamic polydisperse branched polymer", "ispublished": "pub", "full_text_status": "public", "keywords": "water structure; molecular dynamics; liquid\u2013liquid critical point; radial distribution function; density-functional theory", "note": "\u00a9 2019 National Academy of Sciences. Published under the PNAS license. \n\nContributed by William A. Goddard III, December 17, 2018 (sent for review October 9, 2018; reviewed by Charles L. Brooks III and Michael L. Klein). PNAS published ahead of print January 24, 2019. \n\nWe thank Dr. Sergey Zybin and Prof. Tod Pascal for helpful discussions. S.N. was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. W.A.G. was supported by the Computational Materials Sciences Program funded by the US DOE, Office of Science, Basic Energy Sciences, under Award DE-SC00014607. The calculations were carried out on the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1548562. \n\nAuthor contributions: S.N. and W.A.G. designed research; S.N. performed research; S.N. and W.A.G. analyzed data; and S.N. and W.A.G. wrote the paper. \n\nReviewers: C.L.B., University of Michigan; and M.L.K., Temple University. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1817383116/-/DCSupplemental.\n\nPublished - 1998.full.pdf
Supplemental Material - pnas.1817383116.sapp.pdf
Supplemental Material - pnas.1817383116.sm01.mp4
Supplemental Material - pnas.1817383116.sm02.mp4
Supplemental Material - pnas.1817383116.sm03.mp4
", "abstract": "We developed the RexPoN force field for water based entirely on quantum mechanics. It predicts the properties of water extremely accurately, with T_(melt) = 273.3 K (273.15 K) and properties at 298 K: \u0394H_(vap) = 10.36 kcal/mol (10.52), density = 0.9965 g/cm\u00b3 (0.9965), entropy = 68.4 J/mol/K (69.9), and dielectric constant = 76.1 (78.4), where experimental values are in parentheses. Upon heating from 0.0 K (ice) to 273.0 K (still ice), the average number of strong hydrogen bonds (SHBs, r_(OO) \u2264 2.93 \u00c5) decreases from 4.0 to 3.3, but upon melting at 273.5 K, the number of SHBs drops suddenly to 2.3, decreasing slowly to 2.1 at 298 K and 1.6 at 400 K. The lifetime of the SHBs is 90.3 fs at 298 K, increasing monotonically for lower temperature. These SHBs connect to form multibranched polymer chains (151 H\u2082O per chain at 298 K), where branch points have 3 SHBs and termination points have 1 SHB. This dynamic fluctuating branched polymer view of water provides a dramatically modified paradigm for understanding the properties of water. It may explain the 20-nm angular correlation lengths at 298 K and the critical point at 227 K in supercooled water. Indeed, the 15% jump in the SHB lifetime at 227 K suggests that the supercooled critical point may correspond to a phase transition temperature of the dynamic polymer structure. This paradigm for water could have a significant impact on the properties for protein, DNA, and other materials in aqueous media.", "date": "2019-02-05", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "116", "number": "6", "publisher": "National Academy of Sciences", "pagerange": "1998-2003", "id_number": "CaltechAUTHORS:20190125-105921884", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190125-105921884", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00014607" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1316", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1817383116", "pmcid": "PMC6369747", "primary_object": { "basename": "pnas.1817383116.sm02.mp4", "url": "https://authors.library.caltech.edu/records/3d7kb-qhe12/files/pnas.1817383116.sm02.mp4" }, "related_objects": [ { "basename": "pnas.1817383116.sm03.mp4", "url": "https://authors.library.caltech.edu/records/3d7kb-qhe12/files/pnas.1817383116.sm03.mp4" }, { "basename": "1998.full.pdf", "url": "https://authors.library.caltech.edu/records/3d7kb-qhe12/files/1998.full.pdf" }, { "basename": "pnas.1817383116.sapp.pdf", "url": "https://authors.library.caltech.edu/records/3d7kb-qhe12/files/pnas.1817383116.sapp.pdf" }, { "basename": "pnas.1817383116.sm01.mp4", "url": "https://authors.library.caltech.edu/records/3d7kb-qhe12/files/pnas.1817383116.sm01.mp4" } ], "pub_year": "2019", "author_list": "Naserifar, Saber and Goddard, William A., III" }, { "id": "https://authors.library.caltech.edu/records/f8h1a-cjm88", "eprint_id": 93013, "eprint_status": "archive", "datestamp": "2023-08-19 14:13:10", "lastmod": "2023-10-20 16:44:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Kang-Jun", "name": { "family": "Kang", "given": "Jun" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } } ] }, "title": "Density functional theory based neural network force fields from energy decompositions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 American Physical Society. \n\nReceived 24 September 2018; revised manuscript received 14 December 2018; published 6 February 2019. \n\nWe thank Dr. Ling Miao for the help in evaluating the force field energies in Fig. 6(d). This work was supported by the Director, Office of Science, Office of Basic Energy Science, Materials Science and Engineering Division, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231, through the Material Theory (KC2301) program in Lawrence Berkeley National Laboratory. The work performed by Y.H. and W.A.G. was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work uses the resource of the National Energy Research Scientific Computing Center (NERSC) as well as the Oak Ridge Leadership Computing Facility through the INCITE project.\n\nPublished - PhysRevB.99.064103.pdf
Supplemental Material - DFT_based_Neural_Network_Force_fields_from_Energy_Decompositions_-_Huang_Kang_Goddard_Wang_-18Jan-SM.pdf
", "abstract": "In order to develop force fields (FF) for molecular dynamics simulations that retain the accuracy of ab initio density functional theory (DFT), we developed a machine learning protocol based on an energy decomposition scheme that extracts atomic energies from DFT calculations. Our DFT to FF (DFT2FF) approach provides almost hundreds of times more data for the DFT energies, which dramatically improves accuracy with less DFT calculations. In addition, we use piecewise cosine basis functions to systematically construct symmetry invariant features into the neural network model. We illustrate this DFT2FF approach for amorphous silicon where only 800 DFT configurations are sufficient to achieve an accuracy of 1 meV/atom for energy and 0.1 eV/A for forces. We then use the resulting FF model to calculate the thermal conductivity of amorphous Si based on long molecular dynamics simulations. The dramatic speedup in training in our DFT2FF protocol allows the adoption of a simulation paradigm where an accurate and problem specific FF for a given physics phenomenon is trained on-the-spot through a quick DFT precalculation and FF training.", "date": "2019-02-01", "date_type": "published", "publication": "Physical Review B", "volume": "99", "number": "6", "publisher": "American Physical Society", "pagerange": "Art. No. 064103", "id_number": "CaltechAUTHORS:20190221-074413398", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190221-074413398", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1315", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/physrevb.99.064103", "primary_object": { "basename": "DFT_based_Neural_Network_Force_fields_from_Energy_Decompositions_-_Huang_Kang_Goddard_Wang_-18Jan-SM.pdf", "url": "https://authors.library.caltech.edu/records/f8h1a-cjm88/files/DFT_based_Neural_Network_Force_fields_from_Energy_Decompositions_-_Huang_Kang_Goddard_Wang_-18Jan-SM.pdf" }, "related_objects": [ { "basename": "PhysRevB.99.064103.pdf", "url": "https://authors.library.caltech.edu/records/f8h1a-cjm88/files/PhysRevB.99.064103.pdf" } ], "pub_year": "2019", "author_list": "Huang, Yufeng; Kang, Jun; et el." }, { "id": "https://authors.library.caltech.edu/records/v3wt6-ynr73", "eprint_id": 91979, "eprint_status": "archive", "datestamp": "2023-08-19 14:01:00", "lastmod": "2023-10-19 23:52:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Nanoporous Gold as a Highly Selective and Active Carbon Dioxide Reduction Catalyst", "ispublished": "pub", "full_text_status": "public", "keywords": "CO_2 reduction, nanoporous cathode, pH gradient, grain boundaries, electrocatalysis", "note": "\u00a9 2018 American Chemical Society. This article is made available for a limited time sponsored by ACS under the ACS Free to Read License, which permits copying and redistribution of the article for non-commercial scholarly purposes. \n\nReceived: September 17, 2018; Accepted: December 26, 2018; Published: December 26, 2018. \n\nThis work is done within the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the U.S. Department of energy under Award Number De-SC0004993. A.J.W. acknowledges support from the National Science Foundation (NSF) Graduate Research Fellowship Program under Base Award No. 1745301. G.T. acknowledges support from the Swiss National Science Foundation through the Advanced Mobility Fellowship, grant n. P300P2_171417. We gratefully acknowledge critical support and infrastructure provided for this work by the Kavli Nanoscience Institute at Caltech. We thank Matthew S. Hunt of the Kavli Nanoscience Institute at Caltech for assistance with SEM, He FIB, and TEM imaging of nanoporous Au films. Any opinions, findings, and conclusions expressed in this material are those of the authors and do not necessary reflect those of DOE or NSF. \n\nAuthor Contributions: A.J.W., J.S.D., G.T., and H.A.A. conceived of the experimental study. A.J.W. and J.S.D. executed all electrochemical experiments and performed the data analysis. W.-H.C. assisted with gas chromatography and high-pressure liquid chromatography. A.J.W., J.S.D., and H.A.A. wrote the paper, and all authors commented on the manuscript. \n\nThe authors declare no competing financial interest.\n\nPublished - acsaem.8b01570.pdf
Supplemental Material - ae8b01570_si_001.pdf
", "abstract": "Electrochemical conversion of CO_2 into useful chemicals is a promising approach for transforming CO_2 into sustainably produced fuels and/or chemical feedstocks for industrial synthesis. We report that nanoporous gold (np-Au) films, with pore sizes ranging from 10 to 30 nm, represent promising electrocatalytic architectures for the CO_2 reduction reaction (CO_2RR) due to their large electrochemically active surface area, relative abundance of grain boundaries, and ability to support pH gradients inside the nanoporous network. Electrochemical studies show that np-Au films support partial current densities for the conversion of CO_2 to CO in excess of 6 mA cm^(\u20132) at a Faradaic efficiency of \u223c99% in aqueous electrolytes (50 mM K_2CO_3 saturated with CO_2). Moreover, np-Au films are able to maintain Faradaic efficiency greater than 80% for CO production over prolonged periods of continuous operation (110 h). Electrocatalytic experiments at different electrolyte concentrations demonstrate that the pore diameter of nanoporous cathodes represents a critical parameter for creating and controlling local pH gradients inside the porous network of metal ligaments. These results demonstrate the merits of nanoporous metal films for the CO_2RR and offer an interesting architecture for highly selective electrocatalysis capable of sustaining high catalytic currents over prolonged periods.", "date": "2019-01-28", "date_type": "published", "publication": "ACS Applied Energy Materials", "volume": "2", "number": "1", "publisher": "American Chemical Society", "pagerange": "164-170", "id_number": "CaltechAUTHORS:20190102-092234188", "issn": "2574-0962", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-092234188", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1745301" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acsaem.8b01570", "primary_object": { "basename": "acsaem.8b01570.pdf", "url": "https://authors.library.caltech.edu/records/v3wt6-ynr73/files/acsaem.8b01570.pdf" }, "related_objects": [ { "basename": "ae8b01570_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v3wt6-ynr73/files/ae8b01570_si_001.pdf" } ], "pub_year": "2019", "author_list": "Welch, Alex J.; DuChene, Joseph S.; et el." }, { "id": "https://authors.library.caltech.edu/records/7r63r-m5h19", "eprint_id": 92507, "eprint_status": "archive", "datestamp": "2023-08-22 00:44:00", "lastmod": "2023-10-20 15:46:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-Arunima-K", "name": { "family": "Singh", "given": "Arunima K." }, "orcid": "0000-0002-7212-6310" }, { "id": "Montoya-Joseph-H", "name": { "family": "Montoya", "given": "Joseph H." }, "orcid": "0000-0001-5760-2860" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Persson-Kristin-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" } ] }, "title": "Robust and synthesizable photocatalysts for CO\u2082 reduction: a data-driven materials discovery", "ispublished": "pub", "full_text_status": "public", "keywords": "Artificial photosynthesis; Computational chemistry; Corrosion; Photocatalysis", "note": "\u00a9 2019 The Author(s). This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 17 July 2018; Accepted 03 January 2019; Published 25 January 2019. \n\nThis work was primarily funded by the Joint Center for Artificial Photosynthesis, a US Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under Award Number DE-SC0004993. Computational work was additionally supported by the Materials Project Program (Grant No. KC23MP) through the DOE Office of Basic Energy Sciences, Materials Sciences, and Engineering Division, under Contract DE-AC02-05CH11231. Computational resources were provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the DOE under Contract No. DE-AC02-05CH11231. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. This work used XSEDE's Stampede2 at the Texas Advanced Computing Center through allocation #TG-DMR150006. \n\nData availability: The data that support the results within this paper and other findings of this study are available at https://materialsproject.org/#search/materials, the supplementary information and from the corresponding author upon reasonable request. \n\nAuthor Contributions: A.K.S. and K.A.P. conceptualized the project. A.K.S. developed the methodology, performed the simulations, conducted the data analysis reported in this paper and wrote the original draft. J.H.M. helped automate electronic structure simulations. All authors participated in design of the tiered screening pipeline and manuscript editing. K.A.P. and J.M.G. acquired funding for the work and supervised the research reported in the paper. \n\nThe authors declare no competing interests.\n\nPublished - s41467-019-08356-1.pdf
Supplemental Material - 41467_2019_8356_MOESM1_ESM.pdf
", "abstract": "The photocatalytic conversion of the greenhouse gas CO\u2082 to chemical fuels such as hydrocarbons and alcohols continues to be a promising technology for renewable generation of energy. Major advancements have been made in improving the efficiencies and product selectiveness of currently known CO\u2082 reduction electrocatalysts, nonetheless, materials discovery is needed to enable economically viable, industrial-scale CO\u2082 reduction. We report here the largest CO\u2082 photocathode search to date, starting with 68860 candidate materials, using a rational first-principles computation-based screening strategy to evaluate synthesizability, corrosion resistance, visible-light absorption, and compatibility of the electronic structure with fuel synthesis. The results confirm the observation of the literature that few materials meet the stringent CO\u2082 photocathode requirements, with only 52 materials meeting all requirements. The results are well validated with respect to the literature, with 9 of these materials having been studied for CO\u2082 reduction, and the remaining 43 materials are discoveries from our pipeline that merit further investigation.", "date": "2019-01-25", "date_type": "published", "publication": "Nature Communications", "volume": "10", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 443", "id_number": "CaltechAUTHORS:20190129-080508688", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190129-080508688", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "KC23MP" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1548562" }, { "agency": "NSF", "grant_number": "TG-DMR150006" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-019-08356-1", "pmcid": "PMC6347635", "primary_object": { "basename": "41467_2019_8356_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/7r63r-m5h19/files/41467_2019_8356_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41467-019-08356-1.pdf", "url": "https://authors.library.caltech.edu/records/7r63r-m5h19/files/s41467-019-08356-1.pdf" } ], "pub_year": "2019", "author_list": "Singh, Arunima K.; Montoya, Joseph H.; et el." }, { "id": "https://authors.library.caltech.edu/records/e563g-7md49", "eprint_id": 91854, "eprint_status": "archive", "datestamp": "2023-08-19 13:54:02", "lastmod": "2023-10-19 23:46:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "P. F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Guevarra-D", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Umehara-M", "name": { "family": "Umehara", "given": "M." }, "orcid": "0000-0001-8665-0028" }, { "id": "Boyd-D-A", "name": { "family": "Boyd", "given": "D. A." } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "L." }, "orcid": "0000-0002-7052-266X" }, { "id": "Cooper-J-K", "name": { "family": "Cooper", "given": "J. K." }, "orcid": "0000-0002-7953-4229" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Multi-modal optimization of bismuth vanadate photoanodes via combinatorial alloying and hydrogen processing", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nReceived 3rd September 2018, Accepted 6th December 2018. First published on 6th December 2018. \n\nThis work is performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC00049. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c8cc07156j1_si.pdf
", "abstract": "Alloying transition metals, such as Mo, into BiVO_4 has emerged as the primary mechanism for improving carrier transport in this photoanode for solar fuels production. The present work establishes the generality of improving photoelectrochemical performance through co-alloying with a transition metal electron donor and a structure-modulating rare earth. Further improvement for all such alloys is obtained by annealing the oxide materials in H_2, ultimately producing photoanodes with above 3 mA cm^(\u22122) photocurrent density under AM 1.5G illumination, in the top tier of compact BiVO_4 films.", "date": "2019-01-14", "date_type": "published", "publication": "Chemical Communications", "volume": "55", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "489-492", "id_number": "CaltechAUTHORS:20181217-090927342", "issn": "1359-7345", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-090927342", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00049" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c8cc07156j", "primary_object": { "basename": "c8cc07156j1_si.pdf", "url": "https://authors.library.caltech.edu/records/e563g-7md49/files/c8cc07156j1_si.pdf" }, "pub_year": "2019", "author_list": "Newhouse, P. F.; Guevarra, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/mza73-yw131", "eprint_id": 91849, "eprint_status": "archive", "datestamp": "2023-08-19 13:51:35", "lastmod": "2023-10-19 23:46:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Higgins-D-C", "name": { "family": "Higgins", "given": "Drew" }, "orcid": "0000-0002-0585-2670" }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" } ] }, "title": "Gas-Diffusion Electrodes for Carbon-Dioxide Reduction: A New Paradigm", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 24, 2018; Accepted: December 14, 2018;\nPublished: December 14, 2018.\n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nAuthor Contributions:\nD.H. and C.H.: Equal author contributions.\n\nThe authors declare no competing financial interest.", "abstract": "Significant advances have been made in recent years discovering new electrocatalysts and developing a fundamental understanding of electrochemical CO_2 reduction processes. This field has progressed to the point that efforts can now focus on translating this knowledge toward the development of practical CO_2 electrolyzers, which have the potential to replace conventional petrochemical processes as a sustainable route to produce fuels and chemicals. In this Perspective, we take a critical look at the progress in incorporating electrochemical CO_2 reduction catalysts into practical device architectures that operate using vapor-phase CO_2 reactants, thereby overcoming intrinsic limitations of aqueous-based systems. Performance comparison is made between state-of-the-art CO_2 electrolyzers and commercial H_2O electrolyzers\u2014a well-established technology that provides realistic performance targets. Beyond just higher rates, vapor-fed reactors represent new paradigms for unprecedented control of local reaction conditions, and we provide a perspective on the challenges and opportunities for generating fundamental knowledge and achieving technological progress toward the development of practical CO_2 electrolyzers.", "date": "2019-01-11", "date_type": "published", "publication": "ACS Energy Letters", "volume": "4", "number": "1", "publisher": "American Chemical Society", "pagerange": "317-324", "id_number": "CaltechAUTHORS:20181217-081303242", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-081303242", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b02035", "pub_year": "2019", "author_list": "Higgins, Drew; Hahn, Christopher; et el." }, { "id": "https://authors.library.caltech.edu/records/y40vd-sw766", "eprint_id": 88353, "eprint_status": "archive", "datestamp": "2023-08-19 13:47:54", "lastmod": "2023-10-20 22:08:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Stein-Helge-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Soedarmadji-Edwin", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Machine learning of optical properties of materials - predicting spectra from images and images from spectra", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2019 The Royal Society of Chemistry. Open Access Article. This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. \n\nAll publication charges for this article have been paid for by the Royal Society of Chemistry. \n\nThe article was received on 11 Jul 2018, accepted on 24 Oct 2018 and first published on 25 Oct 2018. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). \n\nThere are no conflicts to declare.\n\nPublished - c8sc03077d.pdf
Submitted - autoencoder_chemrxivsubmit1.pdf
Supplemental Material - c8sc03077d1_s1.zip
Supplemental Material - c8sc03077d2_s2.zip
Supplemental Material - c8sc03077d3_s3.pdf
", "abstract": "As the materials science community seeks to capitalize on recent advancements in computer science, the sparsity of well-labelled experimental data and limited throughput by which it can be generated have inhibited deployment of machine learning algorithms to date. Several successful examples in computational chemistry have inspired further adoption of machine learning algorithms, and in the present work we present autoencoding algorithms for measured optical properties of metal oxides, which can serve as an exemplar for the breadth and depth of data required for modern algorithms to learn the underlying structure of experimental materials science data. Our set of 178\u2006994 distinct materials samples spans 78 distinct composition spaces, includes 45 elements, and contains more than 80\u2006000 unique quinary oxide and 67\u2006000 unique quaternary oxide compositions, making it the largest and most diverse experimental materials set utilized in machine learning studies. The extensive dataset enabled training and validation of 3 distinct models for mapping between sample images and absorption spectra, including a conditional variational autoencoder that generates images of hypothetical materials with tailored absorption properties. The absorption patterns auto-generated from sample images capture the salient features of ground truth spectra, and band gap energies extracted from these auto-generated patterns are quite accurate with a mean absolute error of 180 meV, which is the approximate uncertainty from traditional extraction of the band gap energy from measurements of the full transmission and reflection spectra. Optical properties of materials are not only ubiquitous in materials applications but also emblematic of the confluence of underlying physical phenomena yielding the type of complex data relationships that merit and benefit from neural network-type modelling.", "date": "2019-01-07", "date_type": "published", "publication": "Chemical Science", "volume": "10", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "47-55", "id_number": "CaltechAUTHORS:20180730-104921622", "issn": "2041-6520", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180730-104921622", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Royal Society of Chemistry" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c8sc03077d", "pmcid": "PMC6334722", "primary_object": { "basename": "autoencoder_chemrxivsubmit1.pdf", "url": "https://authors.library.caltech.edu/records/y40vd-sw766/files/autoencoder_chemrxivsubmit1.pdf" }, "related_objects": [ { "basename": "c8sc03077d.pdf", "url": "https://authors.library.caltech.edu/records/y40vd-sw766/files/c8sc03077d.pdf" }, { "basename": "c8sc03077d1_s1.zip", "url": "https://authors.library.caltech.edu/records/y40vd-sw766/files/c8sc03077d1_s1.zip" }, { "basename": "c8sc03077d2_s2.zip", "url": "https://authors.library.caltech.edu/records/y40vd-sw766/files/c8sc03077d2_s2.zip" }, { "basename": "c8sc03077d3_s3.pdf", "url": "https://authors.library.caltech.edu/records/y40vd-sw766/files/c8sc03077d3_s3.pdf" } ], "pub_year": "2019", "author_list": "Stein, Helge S.; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/cq5at-xrt54", "eprint_id": 90738, "eprint_status": "archive", "datestamp": "2023-08-22 00:39:35", "lastmod": "2023-10-19 14:48:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Alberi-K", "name": { "family": "Alberi", "given": "Kirstin" }, "orcid": "0000-0002-5236-5568" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John" }, "orcid": "0000-0002-2863-5265" } ] }, "title": "The 2019 materials by design roadmap", "ispublished": "pub", "full_text_status": "public", "keywords": "density functional theory; materials genome initative; materials design; high-throughput methods; energy applications", "note": "\u00a9 2018 IOP Publishing Ltd. Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. \n\nReceived 19 February 2018, revised 25 June 2018; Accepted for publication 9 August 2018; Published 24 October 2018. \n\nS H W was supported by the NSFC under Grant Nos. 11634003, 51672023 and U1530401 and the National Key Research and Development Program of China under Grant No. 2016YFB0700700. J D P was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, as part of the Energy Frontier Research Center- Center for Next Generation of Materials Design under Contract No. DE-AC36-08GO28308 to NREL.\n\nPublished - Alberi_2019_J._Phys._D_3A_Appl._Phys._52_013001.pdf
", "abstract": "Advances in renewable and sustainable energy technologies critically depend on our ability to design and realize materials with optimal properties. Materials discovery and design efforts ideally involve close coupling between materials prediction, synthesis and characterization. The increased use of computational tools, the generation of materials databases, and advances in experimental methods have substantially accelerated these activities. It is therefore an opportune time to consider future prospects for materials by design approaches. The purpose of this Roadmap is to present an overview of the current state of computational materials prediction, synthesis and characterization approaches, materials design needs for various technologies, and future challenges and opportunities that must be addressed. The various perspectives cover topics on computational techniques, validation, materials databases, materials informatics, high-throughput combinatorial methods, advanced characterization approaches, and materials design issues in thermoelectrics, photovoltaics, solid state lighting, catalysts, batteries, metal alloys, complex oxides and transparent conducting materials. It is our hope that this Roadmap will guide researchers and funding agencies in identifying new prospects for materials design.", "date": "2019-01-02", "date_type": "published", "publication": "Journal of Physics D: Applied Physics", "volume": "52", "number": "1", "publisher": "IOP", "pagerange": "Art. No. 013001", "id_number": "CaltechAUTHORS:20181108-080822303", "issn": "0022-3727", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181108-080822303", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "11634003" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51672023" }, { "agency": "National Natural Science Foundation of China", "grant_number": "U1530401" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2016YFB0700700" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1088/1361-6463/aad926", "primary_object": { "basename": "Alberi_2019_J._Phys._D_3A_Appl._Phys._52_013001.pdf", "url": "https://authors.library.caltech.edu/records/cq5at-xrt54/files/Alberi_2019_J._Phys._D_3A_Appl._Phys._52_013001.pdf" }, "pub_year": "2019", "author_list": "Alberi, Kirstin and Gregoire, John" }, { "id": "https://authors.library.caltech.edu/records/7vafc-kct91", "eprint_id": 90953, "eprint_status": "archive", "datestamp": "2023-08-19 13:44:28", "lastmod": "2023-10-19 15:02:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Guiji", "name": { "family": "Liu", "given": "Guiji" }, "orcid": "0000-0002-3943-4119" }, { "id": "Eichhorn-Johanna", "name": { "family": "Eichhorn", "given": "Johanna" }, "orcid": "0000-0003-2413-6079" }, { "id": "Jiang-Chang-Ming", "name": { "family": "Jiang", "given": "Chang-Ming" }, "orcid": "0000-0001-8327-5760" }, { "id": "Scott-Mary-C", "name": { "family": "Scott", "given": "Mary C." } }, { "id": "Hess-Lucas-H", "name": { "family": "Hess", "given": "Lucas H." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" } ] }, "title": "Interface engineering for light-driven water oxidation: unravelling the passivating and catalytic mechanism in BiVO\u2084 overlayers", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 26 Sep 2018, accepted on 12 Oct 2018 and first published on 12 Oct 2018. \n\nThis study is based on work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c8se00473k1_si.pdf
", "abstract": "Artificial photosynthetic approaches require the combination of light absorbers interfaced with overlayers that enhance charge transport and collection to perform catalytic reactions. Despite numerous efforts that have coupled various catalysts to light absorbing semiconductors, the optimization of semiconductor/catalyst as well as catalyst/electrolyte interfaces and the identification of the role of the catalyst still remain a key challenge. Herein, we assemble (NiFeCoCe)O\u2093 multi-component overlayers, interfaced with bismuth vanadate photoanodes, and determine the roles of different elements on promoting interfacial charge transfer and catalytic reaction over competitive photocarrier recombination loss processes. Through this understanding, and aided by complementary macroscopic photoelectrochemical measurements and nanoscale atomic force microscopy techniques, a bifunctional (CoFeCe/NiFe)O\u2093 overlayer was rationally engineered. The resulting multi-functional coating yields BiVO\u2084 photoanodes with almost 100% efficient surface collection of holes under oxygen evolving reaction conditions. The (CoFeCe)O\u2093 component excels at efficient capture and transport of photogenerated holes in BiVO\u2084 through the availability of redox active states, whereas (NiFe)O\u2093 plays a vital role in reducing charge recombination at the BiVO\u2084/electrolyte interface. In addition, this study supports the hypothesis that catalytic sites act as electronically active trap states on uncoated BiVO\u2084 photoanodes.", "date": "2019-01-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "3", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "127-135", "id_number": "CaltechAUTHORS:20181116-091613557", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181116-091613557", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C8SE00473K", "primary_object": { "basename": "c8se00473k1_si.pdf", "url": "https://authors.library.caltech.edu/records/7vafc-kct91/files/c8se00473k1_si.pdf" }, "pub_year": "2019", "author_list": "Liu, Guiji; Eichhorn, Johanna; et el." }, { "id": "https://authors.library.caltech.edu/records/8p281-9rt86", "eprint_id": 91853, "eprint_status": "archive", "datestamp": "2023-08-19 13:45:01", "lastmod": "2023-10-19 23:46:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Finke-Cody-E", "name": { "family": "Finke", "given": "Cody E." }, "orcid": "0000-0002-1343-1737" }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Jasper-Justin-T", "name": { "family": "Jasper", "given": "Justin T." }, "orcid": "0000-0002-2461-5283" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Read-Carlos-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Hoffmann-M-R", "name": { "family": "Hoffmann", "given": "Michael R." }, "orcid": "0000-0001-6495-1946" } ] }, "title": "Enhancing the activity of oxygen-evolution and chlorine-evolution electrocatalysts by atomic layer deposition of TiO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. \n\nThe article was received on 12 Aug 2018, accepted on 26 Nov 2018 and first published on 14 Dec 2018. \n\nSupporting data referenced above may be found in the ESI. This work was supported by the Bill and Melinda Gates Foundation (BMGF RTTC Grants OPP1111246 and OPP1149755). Research was in part carried out at the Molecular Materials Resource Center of the Beckman Institute of the California Institute of Technology. Funding was provided to C. E. F., J. T. J., and C. G. R. by the Resnick Institute for Sustainability at Caltech. In part, this material is based upon work by S. T. O. and N. S. L. performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. C. E. F. was the primary concept generator for this work, led electrocatalyst activity, E_(ZC), and AFM data collection and analysis, and helped fabricate and characterize the electrocatalysts. S. T. O. helped to generate the concept for this work, fabricated and characterized the electrocatalysts, and helped with data analysis and experimental design. J. T. J. helped generate the concept of this work, helped design the electrochemical methodology, and helped collect electrochemical data. M. F. L. collected the XPS data and assisted in the fitting and analysis of XPS and impedance spectroscopy data. C. G. R. lead TEM characterization of the electro catalysts. C. E. F., S. T. O., and J. T. J. prepared the manuscript and N. S. L., M. R. H., M. F. L., and C. G. R. helped with its editing. All authors reviewed and contributed to the final manuscript. We would like to acknowledge Dr Katharina Urmann and Sisir Yalamanchili for help dicing Si wafers, Jingjing Jiang for help analyzing AFM data, and Azhar Carim for help with SEM, and Laleh Majari Kasmaee for help with E_(ZC) analysis. We acknowledge Prof. Stefan Zweifel and his group for foundational mentoring as well as Prof. Gretchen Hofmeister and Prof. Matt Whited for foundational chemical insight. \n\nConflicts of interest: The authors' institution (California Institute of Technology) has filed a U.S. patent application directly relating to the work described in the paper (patent application no. US20180087164A1, filed on Sept. 28, 2017).\n\nPublished - c8ee02351d.pdf
Supplemental Material - c8ee02351d1_si.pdf
", "abstract": "We report that TiO\u2082 coatings formed via atomic layer deposition (ALD) may tune the activity of IrO\u2082, RuO\u2082, and FTO for the oxygen-evolution and chlorine-evolution reactions (OER and CER). Electrocatalysts exposed to \u223c3\u201330 ALD cycles of TiO\u2082 exhibited overpotentials at 10 mA cm\u207b\u00b2 of geometric current density that were several hundred millivolts lower than uncoated catalysts, with correspondingly higher specific activities. For example, the deposition of TiO\u2082 onto IrO\u2082 yielded a 9-fold increase in the OER-specific activity in 1.0 M H\u2082SO\u2084 (0.1 to 0.9 mA cm_(ECSA)\u207b\u00b2 at 350 mV overpotential). The oxidation state of titanium and the potential of zero charge were also a function of the number of ALD cycles, indicating a correlation between oxidation state, potential of zero charge, and activity of the tuned electrocatalysts.", "date": "2019-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "12", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "358-365", "id_number": "CaltechAUTHORS:20181217-085437866", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-085437866", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1111246" }, { "agency": "Bill and Melinda Gates Foundation", "grant_number": "OPP1149755" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1039/c8ee02351d", "pmcid": "PMC7680952", "primary_object": { "basename": "c8ee02351d.pdf", "url": "https://authors.library.caltech.edu/records/8p281-9rt86/files/c8ee02351d.pdf" }, "related_objects": [ { "basename": "c8ee02351d1_si.pdf", "url": "https://authors.library.caltech.edu/records/8p281-9rt86/files/c8ee02351d1_si.pdf" } ], "pub_year": "2019", "author_list": "Finke, Cody E.; Omelchenko, Stefan T.; et el." }, { "id": "https://authors.library.caltech.edu/records/s2axe-fm549", "eprint_id": 90870, "eprint_status": "archive", "datestamp": "2023-08-19 13:17:07", "lastmod": "2023-10-19 14:58:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Chen-Yalu", "name": { "family": "Chen", "given": "Yalu" }, "orcid": "0000-0002-0589-845X" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Identification of the Selective Sites for Electrochemical Reduction of CO to C_(2+) Products on Copper Nanoparticles by Combining Reactive Force Fields, Density Functional Theory, and Machine Learning", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 9, 2018; Accepted: November 8, 2018; Published: November 8, 2018. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This material is also based upon work supported by the U.S. Department of Energy, Office of Science, Office of Workforce Development for Teachers and Scientists, Office of Science Graduate Student Research (SCGSR) program. The SCGSR program is administered by the Oak Ridge Institute for Science and Education for the DOE under contract number DE-SC0014664. This work uses the resource of National Energy Research Scientific Computing center (NERSC). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz8b01933_si_001.pdf
", "abstract": "Recent experiments have shown that CO reduction on oxide derived Cu nanoparticles (NP) are highly selective toward C_(2+) products. However, understanding of the active sites on such NPs is limited, because the NPs have \u223c200\u202f000 atoms with more than 10\u202f000 surface sites, far too many for direct quantum mechanical calculations and experimental identifications. We show here how to overcome the computational limitation by combining multiple levels of theoretical computations with machine learning. This approach allows us to map the machine learned CO adsorption energies on the surface of the copper nanoparticle to construct the active site visualization (ASV). Furthermore, we identify the structural criteria for optimizing selective reduction by predicting the reaction energies of the potential determining step, \u0394E_(OCCOH), for the C_(2+) product. Based on this structural criterion, we design a new periodic copper structure for CO reduction with a theoretical faradaic efficiency of 97%.", "date": "2018-12-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "12", "publisher": "American Chemical Society", "pagerange": "2983-2988", "id_number": "CaltechAUTHORS:20181113-112609899", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181113-112609899", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE\u2010SC0014664" } ] }, "other_numbering_system": { "items": [ { "id": "1308", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b01933", "primary_object": { "basename": "nz8b01933_si_001.pdf", "url": "https://authors.library.caltech.edu/records/s2axe-fm549/files/nz8b01933_si_001.pdf" }, "pub_year": "2018", "author_list": "Huang, Yufeng; Chen, Yalu; et el." }, { "id": "https://authors.library.caltech.edu/records/99rb3-0bs33", "eprint_id": 90304, "eprint_status": "archive", "datestamp": "2023-08-19 13:11:20", "lastmod": "2023-10-18 23:21:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Montoya-J-H", "name": { "family": "Montoya", "given": "Joseph H." }, "orcid": "0000-0001-5760-2860" }, { "id": "Singh-Arunima-K", "name": { "family": "Singh", "given": "Arunima" }, "orcid": "0000-0002-7212-6310" }, { "id": "Gul-S", "name": { "family": "Gul", "given": "Sheraz" }, "orcid": "0000-0001-8920-8737" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Ye-Yifan", "name": { "family": "Ye", "given": "Yifan" } }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Cooper-J-K", "name": { "family": "Cooper", "given": "Jason K." }, "orcid": "0000-0002-7953-4229" }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Rutile alloys in the Mn-Sb-O system stabilize Mn^(+3) to enable oxygen evolution in strong acid", "ispublished": "pub", "full_text_status": "public", "keywords": "oxygen evolution reaction, catalysis, electrochemical stability, metal oxide alloys, combinatorial materials science", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: July 10, 2018; Revised: October 5, 2018; Published: October 16, 2018. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award DE-SC0004993). Computational work was additionally supported by the Materials Project Program (Grant KC23MP) through the DOE Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02-05CH11231. Computational resources were provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the DOE under Contract DE-AC02-05CH11231. Part of this work (XAS data collection) was carried out at Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. XAS studies were performed with support of the Office of Science, OBES, Division of Chemical Sciences, Geosciences, and Biosciences (CSGB) of the DOE under Contract DE-AC02-05CH11231 (J. Yano). AP-XPS was carried out at Advanced Light Source, Lawrence Berkeley National Laboratory, supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-05CH11231. We acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center that enabled vacuum XPS characterization. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs8b02689_si_001.pdf
", "abstract": "Electrocatalysis of the oxygen evolution reaction is central to several energy technologies including electrolyzers, solar fuel generators, and air-breathing batteries. Strong acid electrolytes are desirable for many implementations of these technologies, although the deployment of such device designs is often hampered by the lack of non-precious-metal oxygen evolution electrocatalysts, with Ir-based oxides comprising the only known catalysts that exhibit stable activity at low overpotential. During our exploration of the Mn\u2013Sb\u2013O system for precious-metal-free electrocatalysts, we discovered that Mn can be incorporated into the rutile oxide structure at much higher concentrations than previously known, and that these Mn-rich rutile alloys exhibit great catalytic activity with current densities exceeding 50 mA cm^(\u20132) at 0.58 V overpotential and catalysis onset at 0.3 V overpotential. While this activity does not surpass that of IrO_2, Pourbaix analysis reveals that the Mn\u2013Sb rutile oxide alloys have the same or better thermodynamic stability under operational conditions. By combining combinatorial composition, structure, and activity mapping with synchrotron X-ray absorption measurements and first-principles materials chemistry calculations, we provide a comprehensive understanding of these oxide alloys and identify the critical role of Sb in stabilizing the trivalent Mn octahedra that have been shown to be effective oxygen evolution reaction (OER) catalysts.", "date": "2018-12-07", "date_type": "published", "publication": "ACS Catalysis", "volume": "8", "number": "12", "publisher": "American Chemical Society", "pagerange": "10938-10948", "id_number": "CaltechAUTHORS:20181017-092736202", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181017-092736202", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "KC23MP" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.8b02689", "primary_object": { "basename": "cs8b02689_si_001.pdf", "url": "https://authors.library.caltech.edu/records/99rb3-0bs33/files/cs8b02689_si_001.pdf" }, "pub_year": "2018", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/76c7h-22374", "eprint_id": 90764, "eprint_status": "archive", "datestamp": "2023-08-19 13:10:28", "lastmod": "2023-10-19 14:50:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "The Reaction Mechanism for the Hydrogen Evolution Reaction on the Basal Plane Sulfur Vacancy Site of MoS_2 Using Grand Canonical Potential Kinetics", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrochemistry, Grand Canonical Potential, Hydrogen Evolution Reaction, Molybdenum Disulfide", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: September 14, 2018; Published: November 8, 2018. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work uses the resource of National Energy Research Scientific Computing center (NERSC). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b10016_si_001.pdf
", "abstract": "We develop the grand canonical potential kinetics (GCP-K) formulation based on thermodynamics from quantum mechanics calculations to provide a fundamental basis for understanding heterogeneous electrochemical reactions. Our GCP-K formulation arises naturally from minimizing the free energy using a Legendre transform relating the net charge of the system and the applied voltage. Performing this macroscopic transformation explicitly allows us to make the connection of GCP-K to the traditional Butler\u2013Volmer kinetics. Using this GCP-K based free energy, we show how to predict both the potential and pH dependent chemistry for a specific example, the hydrogen evolution reaction (HER) at a sulfur vacancy on the basal plane of MoS_2. We find that the rate-determining steps in both acidic and basic conditions are the Volmer reaction in which the second hydrogen atom is adsorbed from the solution. Using the GCP-K formulation, we show that the stretched bond distances change continuously as a function of the applied potential. This shows that the main reason for the higher activity in basic conditions is that the transition state is closer to the product, which leads to a more favorable Tafel slope of 60 mV/dec. In contrast if the transition state were closer to the reactant, where the transfer coefficient is less than 0.5 we would obtain a Tafel slope of almost 150 mV/dec. Based on this detailed understanding of the reaction mechanism, we conclude that the second hydrogen at the chalcogenide vacant site is the most active toward the hydrogen evolution reaction. Using this as a descriptor, we compare it to the other 2H group VI metal dichalcogenides and predict that vacancies on MoTe_2 will have the best performance toward HER.", "date": "2018-12-05", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "48", "publisher": "American Chemical Society", "pagerange": "16773-16782", "id_number": "CaltechAUTHORS:20181108-141108999", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181108-141108999", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1292", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b10016", "primary_object": { "basename": "ja8b10016_si_001.pdf", "url": "https://authors.library.caltech.edu/records/76c7h-22374/files/ja8b10016_si_001.pdf" }, "pub_year": "2018", "author_list": "Huang, Yufeng; Nielsen, Robert J.; et el." }, { "id": "https://authors.library.caltech.edu/records/trwxy-v4y42", "eprint_id": 91847, "eprint_status": "archive", "datestamp": "2023-08-19 13:00:55", "lastmod": "2023-10-19 23:46:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shen-Heping", "name": { "family": "Shen", "given": "Heping" }, "orcid": "0000-0002-8409-8839" }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Jacobs-Daniel-A", "name": { "family": "Jacobs", "given": "Daniel A." }, "orcid": "0000-0002-6267-9827" }, { "id": "Yalamanchili-Sisir", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Wan-Yimao", "name": { "family": "Wan", "given": "Yimao" }, "orcid": "0000-0003-2999-2464" }, { "id": "Yan-Di", "name": { "family": "Yan", "given": "Di" }, "orcid": "0000-0003-2179-3188" }, { "id": "Phang-Pheng", "name": { "family": "Phang", "given": "Pheng" } }, { "id": "Duong-The", "name": { "family": "Duong", "given": "The" } }, { "id": "Wu-Yiliang", "name": { "family": "Wu", "given": "Yiliang" }, "orcid": "0000-0002-5369-2130" }, { "id": "Yin-Yanting", "name": { "family": "Yin", "given": "Yanting" }, "orcid": "0000-0003-0379-1816" }, { "id": "Samundsett-Christian", "name": { "family": "Samundsett", "given": "Christian" } }, { "id": "Peng-Jun", "name": { "family": "Peng", "given": "Jun" } }, { "id": "Wu-Nandi", "name": { "family": "Wu", "given": "Nandi" } }, { "id": "White-Thomas-P", "name": { "family": "White", "given": "Thomas P." }, "orcid": "0000-0001-8493-9450" }, { "id": "Andersson-Gunther-G", "name": { "family": "Andersson", "given": "Gunther G." }, "orcid": "0000-0001-5742-3037" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Catchpole-Kylie-R", "name": { "family": "Catchpole", "given": "Kylie R." }, "orcid": "0000-0003-4858-1820" } ] }, "title": "In situ recombination junction between p-Si and TiO_2 enables high-efficiency monolithic perovskite/Si tandem cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works. Distributed under a Creative Commons Attribution NonCommercial License 4.0 (CC BY-NC). \n\nSubmitted 1 August 2018; Accepted 15 November 2018; Published 14 December 2018. \n\nWe would like to thank S. Surve for the mask fabrication and D. Sheng for the STEM results discussion. We greatly appreciate T. Lu and Y. Liu for help with the AFM measurement, D. Walter and T. Kho for discussion about the passivation of Si solar cells, P. Zhang, Y. Zhang, and L. Wang for coordination of the EQE measurement, W. Liang for optimization of the texturing process, and H. T. Nguyen for optical analysis. The electron spectroscopy apparatus was built with a grant from the Australian Research Council (LE0989068). We acknowledge the equipment and support provided by the Australian Microscopy and Microanalysis Research Facility (AMMRF) and the Australian National Fabrication Facility (ANFF) at the South Australian nodes of the AMMRF and ANFF under the National Collaborative Research Infrastructure Strategy. \n\nThis work was supported by the Australian Government through the Australian Renewable Energy Agency (ARENA), grant MG005, and the Australian Research Council through grant FT13010916. Responsibility for the views, information, or advice expressed herein is not accepted by the Australian Government. Part of the experiment was performed at ANFF ACT Node at the Australian National University. The conception and experimental realization of the TiO_2 deposition and ohmic contact behavior in the tandem solid-state device structure are based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. \n\nAuthor contributions: N.S.L. and K.R.C. supervised the research and coordinated the collaboration. N.S.L., S.T.O., and S.Y. were instrumental in generating the concept for this work. H.S. designed experiments as well as fabricated and characterized devices. D.A.J. helped with data analysis, provided the physical theory, and performed simulations. S.T.O., S.Y., N.W., and Y. Wa. contributed to preparing different TiO2 materials and the design of experiments to characterize the TiO_2/Si contacts. Y. Wa., Y. Wu, T.D., and T.P.W. supplied expertise in tandem design. P.P., C.S., Y. Wu, and D.Y. helped with Si solar cell design and fabrication. T.D. and J.P. assisted in perovskite device fabrication and device stability analysis. Y.Y. and G.G.A. were responsible for the energy level characterization of the ALD-TiO2 layer. H.S. and D.A.J. prepared the manuscript, and N.S.L, K.R.C., S.T.O., and S.Y. helped with its editing. All authors reviewed and contributed to the final manuscript. \n\nCompeting interests: S.T.O., S.Y., and N.S.L. are inventors on a provisional U.S. patent application related to this work filed by the California Institute of Technology (no. 62/662,852, filed 26 April 2018). The authors declare that there are no other competing interests. \n\nData and materials availability: All data needed to evaluate the conclusions in the paper are present in the paper and/or the Supplementary Materials. Additional data related to this paper may be requested from the authors.\n\nPublished - eaau9711.full.pdf
Supplemental Material - aau9711_SM.pdf
", "abstract": "Increasing the power conversion efficiency of silicon (Si) photovoltaics is a key enabler for continued reductions in the cost of solar electricity. Here, we describe a two-terminal perovskite/Si tandem design that increases the Si cell's output in the simplest possible manner: by placing a perovskite cell directly on top of the Si bottom cell. The advantageous omission of a conventional interlayer eliminates both optical losses and processing steps and is enabled by the low contact resistivity attainable between n-type TiO_2 and Si, established here using atomic layer deposition. We fabricated proof-of-concept perovskite/Si tandems on both homojunction and passivating contact heterojunction Si cells to demonstrate the broad applicability of the interlayer-free concept. Stabilized efficiencies of 22.9 and 24.1% were obtained for the homojunction and passivating contact heterojunction tandems, respectively, which could be readily improved by reducing optical losses elsewhere in the device. This work highlights the potential of emerging perovskite photovoltaics to enable low-cost, high-efficiency tandem devices through straightforward integration with commercially relevant Si solar cells.", "date": "2018-12", "date_type": "published", "publication": "Science Advances", "volume": "4", "number": "12", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. eaau9711", "id_number": "CaltechAUTHORS:20181217-073539652", "issn": "2375-2548", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181217-073539652", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Australian Research Council", "grant_number": "LE0989068" }, { "agency": "Australian Renewable Energy Agency", "grant_number": "MG005" }, { "agency": "Australian Research Council", "grant_number": "FT13010916" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1126/sciadv.aau9711", "pmcid": "PMC6294601", "primary_object": { "basename": "aau9711_SM.pdf", "url": "https://authors.library.caltech.edu/records/trwxy-v4y42/files/aau9711_SM.pdf" }, "related_objects": [ { "basename": "eaau9711.full.pdf", "url": "https://authors.library.caltech.edu/records/trwxy-v4y42/files/eaau9711.full.pdf" } ], "pub_year": "2018", "author_list": "Shen, Heping; Omelchenko, Stefan T.; et el." }, { "id": "https://authors.library.caltech.edu/records/6n5q9-8da13", "eprint_id": 91975, "eprint_status": "archive", "datestamp": "2023-08-19 13:01:53", "lastmod": "2023-10-19 23:52:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Wang-Yu", "name": { "family": "Wang", "given": "Yu" }, "orcid": "0000-0003-3589-9274" }, { "id": "Lai-Yungchieh", "name": { "family": "Lai", "given": "Yungchieh" }, "orcid": "0000-0001-9392-1447" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Reactor design and integration with product detection to accelerate screening of electrocatalysts for carbon dioxide reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 AIP Publishing. \n\n(Received 24 July 2018; accepted 2 December 2018; published online 26 December 2018) \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We thank Dr. Lan Zhou for providing the Pd-Au composition spread library.\n\nPublished - 1.5049704.pdf
", "abstract": "Identifying new catalyst materials for complex reactions such as the electrochemical reduction of CO_2 poses substantial instrumentation challenges due to the need to integrate reactor control with electrochemical and analytical instrumentation. Performing accelerated screening to enable exploration of a broad span of catalyst materials poses additional challenges due to the long time scales associated with accumulation of reaction products and the detection of the reaction products with traditional separation-based analytical methods. The catalyst screening techniques that have been reported for combinatorial studies of (photo)electrocatalysts do not meet the needs of CO_2 reduction catalyst research, prompting our development of a new electrochemical cell design and its integration to gas and liquid chromatography instruments. To enable rapid chromatography measurements while maintaining sensitivity to minor products, the electrochemical cell features low electrolyte and head space volumes compared to the catalyst surface area. Additionally, the cell is operated as a batch reactor with electrolyte recirculation to rapidly concentrate reaction products, which serves the present needs for rapidly detecting minor products and has additional implications for enabling product separations in industrial CO_2 electrolysis systems. To maintain near-saturation of CO_2 in aqueous electrolytes, we employ electrolyte nebulization through a CO_2-rich headspace, achieving similar gas-liquid equilibration as vigorous CO_2 bubbling but without gas flow. The instrument is demonstrated with a series of electrochemical experiments on an Au-Pd combinatorial library, revealing non-monotonic variations in product distribution with respect to catalyst composition. The highly integrated analytical electrochemistry system is engineered to enable automation for rapid catalyst screening as well as deployment for a broad range of electrochemical reactions where product distribution is critical to the assessment of catalyst performance.", "date": "2018-12", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "89", "number": "12", "publisher": "American Institute of Physics", "pagerange": "Art. No. 124102", "id_number": "CaltechAUTHORS:20190102-092233752", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190102-092233752", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.5049704", "primary_object": { "basename": "1.5049704.pdf", "url": "https://authors.library.caltech.edu/records/6n5q9-8da13/files/1.5049704.pdf" }, "pub_year": "2018", "author_list": "Jones, Ryan J. R.; Wang, Yu; et el." }, { "id": "https://authors.library.caltech.edu/records/31pc5-jj296", "eprint_id": 91368, "eprint_status": "archive", "datestamp": "2023-08-19 12:52:26", "lastmod": "2023-10-19 22:27:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Hellman-Olle", "name": { "family": "Hellman", "given": "Olle" }, "orcid": "0000-0002-3453-2975" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Electron-Phonon Scattering in the Presence of Soft Modes and Electron Mobility in SrTiO_3 Perovskite from First Principles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Physical Society. \n\n(Received 14 June 2018; published 30 November 2018) \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. M.\u2009B. acknowledges support by the National Science Foundation under Grant No. ACI-1642443, which provided for code development, and Grant No. CAREER-1750613, which provided for theory and method development. This work was partially supported by the Air Force Office of Scientific Research through Young Investigator Program Grant No. FA9550-18-1-0280. O.\u2009H. acknowledges support from the EFRI-2DARE program of the National Science Foundation, Award No. 1433467. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevLett.121.226603.pdf
Accepted Version - 1806.05775
Supplemental Material - SI_for_review.pdf
Supplemental Material - supplemental_material.pdf
", "abstract": "Structural phase transitions and soft phonon modes pose a long-standing challenge to computing electron-phonon (e-ph) interactions in strongly anharmonic crystals. Here we develop a first-principles approach to compute e-ph scattering and charge transport in materials with anharmonic lattice dynamics. Our approach employs renormalized phonons to compute the temperature-dependent e-ph coupling for all phonon modes, including the soft modes associated with ferroelectricity and phase transitions. We show that the electron mobility in cubic SrTiO_3 is controlled by scattering with longitudinal optical phonons at room temperature and with ferroelectric soft phonons below 200 K. Our calculations can accurately predict the temperature dependence of the electron mobility in SrTiO_3 between 150\u2013300 K, and reveal the microscopic origin of its roughly T^(\u22123) trend. Our approach enables first-principles calculations of e-ph interactions and charge transport in broad classes of crystals with phase transitions and strongly anharmonic phonons.", "date": "2018-11-30", "date_type": "published", "publication": "Physical Review Letters", "volume": "121", "number": "22", "publisher": "American Physical Society", "pagerange": "Art. No. 226603", "id_number": "CaltechAUTHORS:20181130-125158827", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181130-125158827", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "NSF", "grant_number": "DMR-1750613" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "NSF", "grant_number": "EFMA-1433467" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/physrevlett.121.226603", "primary_object": { "basename": "1806.05775", "url": "https://authors.library.caltech.edu/records/31pc5-jj296/files/1806.05775" }, "related_objects": [ { "basename": "PhysRevLett.121.226603.pdf", "url": "https://authors.library.caltech.edu/records/31pc5-jj296/files/PhysRevLett.121.226603.pdf" }, { "basename": "SI_for_review.pdf", "url": "https://authors.library.caltech.edu/records/31pc5-jj296/files/SI_for_review.pdf" }, { "basename": "supplemental_material.pdf", "url": "https://authors.library.caltech.edu/records/31pc5-jj296/files/supplemental_material.pdf" } ], "pub_year": "2018", "author_list": "Zhou, Jin-Jian; Hellman, Olle; et el." }, { "id": "https://authors.library.caltech.edu/records/6bcmw-5b408", "eprint_id": 91321, "eprint_status": "archive", "datestamp": "2023-08-22 00:20:15", "lastmod": "2023-10-19 22:24:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "Chu F." } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald C." }, "orcid": "0000-0002-0306-5462" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Kim-Jutae", "name": { "family": "Kim", "given": "Jutae" } }, { "id": "Jerkiewicz-Gregory", "name": { "family": "Jerkiewicz", "given": "Gregory" } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." }, "orcid": "0000-0003-2467-6630" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Potential-Dependent Adsorption of CO and Its Low-Overpotential Reduction to CH_3CH_2OH on Cu(511) Surface Reconstructed from Cu(pc): Operando Studies by Seriatim STM-EQCN-DEMS", "ispublished": "pub", "full_text_status": "public", "keywords": "Surface Science; Electrochemical quartz crystal nanobalance; Potential-dependence of CO adsorption on Cu(511) in KOH; Seriatim STM-EQCN-DEMS", "note": "\u00a9 2018 The Author(s). Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. \n\nManuscript submitted August 10, 2018. Revised manuscript received October 15, 2018. Published November 15, 2018. \n\nThis paper is part of the JES Focus Issue on Electrocatalysis \u2014 In Honor of Radoslav Adzic. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U. S. Department of Energy under Award No. DE-SC0004993.\n\nPublished - J._Electrochem._Soc.-2018-Tsang-J3350-4.pdf
", "abstract": "Operando scanning tunneling microscopy first revealed that application of a CO_2-reduction potential to a Cu(pc) electrode in 0.1 M KOH resulted in the reconstruction of the selvedge to an x-layer stack of well-ordered Cu(100) terraces, Cu(pc)-x[Cu(100)]. Subsequent Cu\u2194Cu_2O oxidation-reduction cycles between \u22120.90 V and 0.10 V SHE converted the reconstructed region to a stepped Cu(S)-[3(100) \u00d7 (111)], or Cu(511), surface. Differential electrochemical mass spectrometry showed that reduction of CO produced only CH_3CH_2OH at the lowest overpotential. Later application of STM and surface infrared spectroscopy uncovered a potential, above which no CO adsorption occurs. In this study, electrochemical quartz crystal nanobalance was combined with STM and DEMS as a prelude to the acquisition of CO coverages as continuous functions of concentration and potential; in heterogeneous catalysis, surface coverage are important since the reaction rate are functions of those quantities. Also equally critical is the knowledge of the packing arrangement at the onset of the reaction because, if \"CO dimers\" were indeed the precursors to C_(2+) products, reduction can only be initiated when the adlayer consists of closely packed CO; otherwise, dimerization will not transpire if the molecules were far apart. The results indicate that the catalysis lags the adsorption, and starts only when CO adsorption is saturated.", "date": "2018-11-16", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "165", "number": "15", "publisher": "Electrochemical Society", "pagerange": "J3350-J3354", "id_number": "CaltechAUTHORS:20181128-160202260", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181128-160202260", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.0451815jes", "primary_object": { "basename": "J._Electrochem._Soc.-2018-Tsang-J3350-4.pdf", "url": "https://authors.library.caltech.edu/records/6bcmw-5b408/files/J._Electrochem._Soc.-2018-Tsang-J3350-4.pdf" }, "pub_year": "2018", "author_list": "Tsang, Chu F.; Javier, Alnald C.; et el." }, { "id": "https://authors.library.caltech.edu/records/5jhty-gvf35", "eprint_id": 90303, "eprint_status": "archive", "datestamp": "2023-08-19 12:40:34", "lastmod": "2023-10-18 23:21:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Bauers-S-R", "name": { "family": "Bauers", "given": "Sage R." } }, { "id": "Zakutayev-A", "name": { "family": "Zakutayev", "given": "Andriy" }, "orcid": "0000-0002-3054-5525" }, { "id": "DuChene-J-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Liu-Guiji", "name": { "family": "Liu", "given": "Guiji" } }, { "id": "Peterson-E-A", "name": { "family": "Peterson", "given": "Elizabeth A." } }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Bi-containing n-FeWO_4 Thin Films Provide the Largest Photovoltage and Highest Stability for a sub-2 eV Band Gap Photoanode", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: August 17, 2018; Accepted: October 12, 2018; Published: October 12, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Computational work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. DOE under Contract DE-AC02-05CH11231. Seebeck and resistivity characterization were supported by the U.S. Department of Energy under Contract No. DE-AC36-08GO28308 with Alliance for Sustainable Energy, LLC, the Manager and Operator of the National Renewable Energy Laboratory, with funding provided by the Office of Science, Office of Basic Energy Sciences, as part of the Energy Frontier Research Center \"Center for Next Generation of Materials Design: Incorporating Metastability\". We thank Dr. Mitsutaro Umehara for assistance with collection of cross-sectional SEM images. \n\nAuthor Contributions: L.Z. and A.S. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz8b01514_si_001.pdf
", "abstract": "Photoelectrocatalysis of the oxygen evolution reaction remains a primary challenge for development of tandem-absorber solar fuel generators due to the lack of a photoanode with broad solar spectrum utilization, a large photovoltage, and stable operation. Bismuth vanadate with a 2.4\u20132.5 eV band gap has shown the most promise becauses its photoactivity down to 0.4 V vs RHE is sufficiently low to couple to a lower-gap photocathode for fuel synthesis. Through development of photoanodes based on the FeWO_4 structure, in particular, Fe-rich variants with addition of about 6% Bi, we demonstrate the same 0.4 V vs RHE turn-on voltage with a 2 eV band gap metal oxide, enabling a 2-fold increase in the device efficiency limit. Combinatorial exploration of materials composition and processing facilitated synthesis of n-type variants of this typical p-type semiconductor that exhibit much higher photoactivity than previous implementations of FeWO_4 in solar photochemistry. The photoanodes are particularly promising for solar fuel applications given their stable operation in acid and base.", "date": "2018-11-09", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "11", "publisher": "American Chemical Society", "pagerange": "2769-2774", "id_number": "CaltechAUTHORS:20181017-090950761", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181017-090950761", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b01514", "primary_object": { "basename": "nz8b01514_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5jhty-gvf35/files/nz8b01514_si_001.pdf" }, "pub_year": "2018", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/se2rq-d4z07", "eprint_id": 90041, "eprint_status": "archive", "datestamp": "2023-08-19 12:05:10", "lastmod": "2023-10-18 23:09:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Stein-Helge-S\u00f6ren", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" } ] }, "title": "Balancing Surface Passivation and Catalysis with Integrated BiVO_4/(Fe-Ce)O_x Photoanodes in pH 9 Borate Electrolyte", "ispublished": "pub", "full_text_status": "public", "keywords": "high-throughput screening, solar fuels, oxygen evolution reaction, photoanode, bismuth vanadate", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: August 17, 2018; Accepted: September 26, 2018;\nPublished: September 26, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nAuthor Contributions: L.Z. and A.S. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ae8b01377_si_001.pdf
", "abstract": "The performance of oxygen-evolving photoanodes based on bismuth vanadate (BiVO_4) is critically determined by the surface coating. While these coatings passivate surface defects, transport photogenerated holes, protect against corrosion, and aid catalysis, their optimal composition changes with operating pH, thus affecting overall performance. We use high-throughput photoelectrochemistry methods to map photoanode performance to enable the discovery of optimal composition and loading of Ce-rich sputter-deposited (Fe\u2013Ce)O_x overlayers on undoped BiVO_4 in pH 9 borate buffer electrolyte. The optimal composition is found to be 20% Fe and 80% Ce with an optimal Fe + Ce metal loading of 0.9 nmol mm^(\u20132). Analysis of the composition and loading dependence of (i) the photocurrent transients upon illumination toggling, (ii) stabilized photocurrent densities, and (iii) photogenerated hole-transfer efficiency reveals the confluence of phenomena that gives rise to the optimal performance yielding nearly perfect transfer efficiency over a narrow composition window.", "date": "2018-10-22", "date_type": "published", "publication": "ACS Applied Energy Materials", "volume": "1", "number": "10", "publisher": "American Chemical Society", "pagerange": "5766-5771", "id_number": "CaltechAUTHORS:20180927-134054550", "issn": "2574-0962", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180927-134054550", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsaem.8b01377", "primary_object": { "basename": "ae8b01377_si_001.pdf", "url": "https://authors.library.caltech.edu/records/se2rq-d4z07/files/ae8b01377_si_001.pdf" }, "pub_year": "2018", "author_list": "Zhou, Lan; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/z83gn-3ne07", "eprint_id": 90162, "eprint_status": "archive", "datestamp": "2023-08-19 11:57:59", "lastmod": "2023-10-18 23:15:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Welborn-M-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Even-handed subsystem selection in projection-based embedding", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 AIP Publishing. \n\n(Received 31 July 2018; accepted 7 September 2018; published online 8 October 2018) \n\nWe thank Feizhi Ding and Sebastian Lee for helpful discussions. M.W. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. T.F.M. acknowledges support in part from the NSF under Award No. CHE-1611581; additionally, this material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. F.R.M. is grateful for funding from EPSRC (Grant No. EP/M013111/1).\n\nPublished - 1.5050533.pdf
Submitted - 1809.03004.pdf
", "abstract": "Projection-based embedding offers a simple framework for embedding correlated wavefunction methods in density functional theory. Partitioning between the correlated wavefunction and density functional subsystems is performed in the space of localized molecular orbitals. However, during a large geometry change\u2014such as a chemical reaction\u2014the nature of these localized molecular orbitals, as well as their partitioning into the two subsystems, can change dramatically. This can lead to unphysical cusps and even discontinuities in the potential energy surface. In this work, we present an even-handed framework for localized orbital partitioning that ensures consistent subsystems across a set of molecular geometries. We illustrate this problem and the even-handed solution with a simple example of an S_N2 reaction. Applications to a nitrogen umbrella flip in a cobalt-based CO_2 reduction catalyst and to the binding of CO to Cu clusters are presented. In both cases, we find that even-handed partitioning enables chemically accurate embedding with modestly sized embedded regions for systems in which previous partitioning strategies are problematic.", "date": "2018-10-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "149", "number": "14", "publisher": "American Institute of Physics", "pagerange": "Art. No. 144101", "id_number": "CaltechAUTHORS:20181008-145630347", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20181008-145630347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.5050533", "primary_object": { "basename": "1.5050533.pdf", "url": "https://authors.library.caltech.edu/records/z83gn-3ne07/files/1.5050533.pdf" }, "related_objects": [ { "basename": "1809.03004.pdf", "url": "https://authors.library.caltech.edu/records/z83gn-3ne07/files/1809.03004.pdf" } ], "pub_year": "2018", "author_list": "Welborn, Matthew; Manby, Frederick R.; et el." }, { "id": "https://authors.library.caltech.edu/records/cgfn9-mv745", "eprint_id": 87889, "eprint_status": "archive", "datestamp": "2023-08-19 11:49:45", "lastmod": "2023-10-18 21:30:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ardo-Shane", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" } ] }, "title": "Pathways to electrochemical solar-hydrogen technologies", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 25 Dec 2017, accepted on 18 Jun 2018 and first published on 19 Jun 2018. \n\nThe authors thank the Lorentz Center for hosting this workshop and all attendees of the workshop for their invaluable input, vision for solar and/or hydrogen technologies, and candid discussions. We are also grateful to other participants who voluntarily are not co-authors on this manuscript: Peter Achterberg, Sjoerd Bakker, Paulien Herder, Lai-Hung Lai, Eric McFarland, Christophe Moser, Rianne Post, and Martijn Van den Berge. The views and opinions expressed in this article are those of the authors and do not necessarily reflect the position of any of their funding agencies. SA thanks the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy, Fuel Cell Technologies Incubator Program under Award No. DE-EE0006963 for support. DFR acknowledges support by The Netherlands Centre for Multiscale Catalytic Energy Conversion (MCEC), an NWO Gravitation programme funded by the Ministry of Education, Culture and Science of the government of The Netherlands. MAM acknowledges the support of New York University, Tandon School of Engineering through his startup grant. VSG and KK acknowledge support by the Dutch NanoNextNL programme funded by the Dutch Ministry of Economic Affairs. Part of the material on photoelectrochemical systems presented in the workshop is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, which provides support for FH. VA thanks the European Commission's Seventh Framework Program (FP7/2007-2013) under grant agreement no. 306398 (FP7-IDEAS-ERS, Project PhotocatH2ode) and Labex Program (ArCANE, ANR-11-LABX-0003-01). TR acknowledges the UK Solar Fuels Network for his travel bursary. The contributions of DFR and HG were carried out within the research programme of BioSolar Cells, co-financed by the Dutch Ministry of Economic Affairs. PW and HG acknowledge the support by the Foundation for Fundamental Research on Matter (FOM, Project No. 13CO12-1), which is part of the Netherlands Organization for Scientific Research (NWO). SG is funded through research grant number 9455 from the VILLUM FONDEN. SMHH thanks Nano-Tera Initiative (Grant no. 20NA21-145936) for financial support. MHT acknowledges NSF-CBET-1602886. FB acknowledges financial support from the research programme of BioSolar Cells, co-financed by the Dutch Ministry of Economic Affairs (project C4.E3). DB acknowledges the financial support of Dieptestrategie program from Zernike Institute for Advanced Materials. SH acknowledges support by the Swiss National Science Foundation through the Starting Grant SCOUTS (grant #155876). The views and opinions of the author(s) expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. \n\nThere are no conflicts to declare.", "abstract": "Solar-powered electrochemical production of hydrogen through water electrolysis is an active and important research endeavor. However, technologies and roadmaps for implementation of this process do not exist. In this perspective paper, we describe potential pathways for solar-hydrogen technologies into the marketplace in the form of photoelectrochemical or photovoltaic-driven electrolysis devices and systems. We detail technical approaches for device and system architectures, economic drivers, societal perceptions, political impacts, technological challenges, and research opportunities. Implementation scenarios are broken down into short-term and long-term markets, and a specific technology roadmap is defined. In the short term, the only plausible economical option will be photovoltaic-driven electrolysis systems for niche applications. In the long term, electrochemical solar-hydrogen technologies could be deployed more broadly in energy markets but will require advances in the technology, significant cost reductions, and/or policy changes. Ultimately, a transition to a society that significantly relies on solar-hydrogen technologies will benefit from continued creativity and influence from the scientific community.", "date": "2018-10-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "11", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2768-2783", "id_number": "CaltechAUTHORS:20180716-131835348", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180716-131835348", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0006963" }, { "agency": "Netherlands Centre for Multiscale Catalytic Energy Conversion (MCEC)" }, { "agency": "Ministry of Education, Culture and Science (Netherlands)" }, { "agency": "New York University" }, { "agency": "Ministry of Economic Affairs (Netherlands)", "grant_number": "C4.E3" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "European Research Council (ERC)", "grant_number": "306398" }, { "agency": "Agence Nationale pour la Recherche (ANR)", "grant_number": "ANR-11-LABX-0003-01" }, { "agency": "UK Solar Fuels Network" }, { "agency": "Stichting voor Fundamenteel Onderzoek der Materie (FOM)", "grant_number": "13CO12-1" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" }, { "agency": "VILLUM FONDEN", "grant_number": "9455" }, { "agency": "Nano-Tera Initiative", "grant_number": "20NA21-145936" }, { "agency": "NSF", "grant_number": "CBET-1602886" }, { "agency": "Zernike Institute" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "155876" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c7ee03639f", "pub_year": "2018", "author_list": "Ardo, Shane and Saadi, Fadl H." }, { "id": "https://authors.library.caltech.edu/records/vbekx-kgx96", "eprint_id": 88603, "eprint_status": "archive", "datestamp": "2023-08-19 11:27:05", "lastmod": "2023-10-18 22:10:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Lu", "name": { "family": "Wang", "given": "Lu" }, "orcid": "0000-0001-5263-3123" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Li-Youyong", "name": { "family": "Li", "given": "Youyong" }, "orcid": "0000-0002-5248-2756" } ] }, "title": "In Silico Optimization of Organic-Inorganic Hybrid Perovskites for Photocatalytic Hydrogen Evolution Reaction in Acidic Solution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: July 31, 2018; Published: August 4, 2018.\n\nThis work was supported by the National Key Research and Development Program of China (Grants 2018YFB0703900, 2017YFA0204800 and 2017YFB0701600), the National Natural Science Foundation of China (51761145013, 21673149). This research was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The work was carried out at National Supercomputer Center in Tianjin, and the calculations were performed on TianHe-1 (A). This project is also supported by the Fund for Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp8b07380_si_001.pdf
", "abstract": "We previously reported the atomistic reaction mechanism for the photocatalytic hydrogen evolution reaction (HER) on the CH_3NH_3PbI_3 organic\u2013inorganic hybrid perovskites based on quantum mechanics calculations of the transition-state barriers, including several layers of explicit acidic solvent. Here, we extend these studies using in silico optimization to discover additional promising photocatalysts. We consider replacing (i) Pb with Sn, (ii) I with Br, and (iii) CH_3NH_3 cation with several organic cations, including NH_2(CH)NH_2 cation as the photocatalyst for HER. We compared the activation barriers and reaction energies for each case. In our previous studies, we found that both H atoms of the H_2 product are extracted from surface organic cations with protons from the solution migrating along Grotthuss water chains to replace the H of the organic cations. This two-step reaction mechanism involves formation of an intermediate lead hydride bond, with the lead atoms and the surface organic cations both playing essential roles. Among the perovskites investigated here, we predict that NH_2(CH)NH_2PbI_3 exhibits the best HER performance with a predicted 10-fold improvement in the reaction rate compared to CH_3NH_3PbI_3. We also suggest that the lead-free tin iodide perovskites might exhibit a rate comparable to that of lead iodide perovskites with the same organic cations. However, replacing iodine by bromine significantly increases the activation barrier. We find for these lead iodide perovskites, the increased proton affinity of the surface organic cations enhances the photocatalytic efficiency, with NH2(CH)NH2 the best case examined.", "date": "2018-09-13", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "122", "number": "36", "publisher": "American Chemical Society", "pagerange": "20918-20922", "id_number": "CaltechAUTHORS:20180806-125347513", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180806-125347513", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2018YFB0703900" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFA0204800" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFB0701600" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51761145013" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21673149" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Priority Academic Program Development of Jiangsu Higher Education Institutions" } ] }, "other_numbering_system": { "items": [ { "id": "1293", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.8b07380", "primary_object": { "basename": "jp8b07380_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vbekx-kgx96/files/jp8b07380_si_001.pdf" }, "pub_year": "2018", "author_list": "Wang, Lu; Goddard, William A., III; et el." }, { "id": "https://authors.library.caltech.edu/records/ry7d7-mrk71", "eprint_id": 86009, "eprint_status": "archive", "datestamp": "2023-08-21 23:56:40", "lastmod": "2023-10-23 15:56:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "P. F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Guevarra-Dan", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "M." }, "orcid": "0000-0001-8665-0028" }, { "id": "Reyes-Lillo-Sebastian-E", "name": { "family": "Reyes-Lillo", "given": "S. E." }, "orcid": "0000-0003-0012-9958" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "L." }, "orcid": "0000-0002-7052-266X" }, { "id": "Boyd-David-A", "name": { "family": "Boyd", "given": "D. A." } }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "S. K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Cooper-Jason-K", "name": { "family": "Cooper", "given": "J. K." }, "orcid": "0000-0002-7953-4229" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "J. B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combinatorial Alloying Improves Bismuth Vanadate Photoanodes via Reduced Monoclinic Distortion", "ispublished": "pub", "full_text_status": "public", "keywords": "Solar Fuels; Bismuth Vanadate Photoanodes; combinatorial chemistry libraries; Computational materials science; Alloys", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 18 Jan 2018, accepted on 06 Jun 2018 and first published on 09 Jun 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Computational work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the US DOE under Contract DE-AC02-05CH11231. \n\nThere are no conflicts to declare.\n\nSubmitted - BVO_alloy_chemrxiv.pdf
Supplemental Material - c8ee00179k1_si.pdf
", "abstract": "Improving the efficiency of solar-powered oxygen evolution is both critical for development of solar fuels technologies and challenging due to the broad set of properties required of a solar fuels photoanode. Bismuth vanadate, in particular the monoclinic clinobisvanite phase, has received substantial attention and has exhibited the highest radiative efficiency among metal oxides with a band gap in the visible range. Efforts to further improve its photoelectrochemical performance have included alloying one or more metals onto the Bi and/or V sites, with progress on this frontier stymied by the difficulty in computational modelling of substitutional alloys and the high dimensionality of co-alloying composition spaces. Since substitutional alloying concurrently changes multiple materials properties, understanding the underlying cause for performance improvements is also challenging, motivating our application of combinatorial materials science techniques to map photoelectrochemical performance of 948 unique bismuth vanadate alloy compositions comprising 0 to 8% alloys of P, Ca, Mo, Eu, Gd, and W along with a variety of compositions from each pairwise combination of these elements. Upon identification of substantial improvements in the (Mo,Gd) co-alloying space, structural mapping was performed to reveal a remarkable correlation between performance enhancement and a lowered monoclinic distortion. First-principles density functional theory calculations indicate that the improvements are due to a lowered hole effective mass and hole polaron formation energy, and collectively, our results identify the monoclinic distortion as a critical parameter in the optimization and understanding of bismuth vanadate-based photoanodes.", "date": "2018-09-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "11", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "2444-2457", "id_number": "CaltechAUTHORS:20180423-104401758", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180423-104401758", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c8ee00179k", "primary_object": { "basename": "BVO_alloy_chemrxiv.pdf", "url": "https://authors.library.caltech.edu/records/ry7d7-mrk71/files/BVO_alloy_chemrxiv.pdf" }, "related_objects": [ { "basename": "c8ee00179k1_si.pdf", "url": "https://authors.library.caltech.edu/records/ry7d7-mrk71/files/c8ee00179k1_si.pdf" } ], "pub_year": "2018", "author_list": "Newhouse, P. F.; Guevarra, D.; et el." }, { "id": "https://authors.library.caltech.edu/records/kkmk9-n1557", "eprint_id": 87651, "eprint_status": "archive", "datestamp": "2023-09-22 22:14:30", "lastmod": "2023-10-23 23:22:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Tin Oxide as a Protective Heterojunction with Silicon for Efficient Photoelectrochemical Water Oxidation in Strongly Acidic or Alkaline Electrolytes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 WILEY\u2010VCH. \n\nReceived: April 16, 2018. Revised: May 26, 2018. Version of Record online: 01 July 2018. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE\u2010SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. I.A.M.\u2010H. acknowledges a National Science Foundation Graduate Research Fellowship under Grant No. DGE\u20101144469. The authors thank C. Garland for assistance with transmission\u2010electron microscopy. \n\nThe authors declare no conflict of interest.\n\nSupplemental Material - downloadSupplement_doi=10.1002_2Faenm.201801155_file=aenm201801155-sup-0001-S1.pdf
", "abstract": "Photoelectrodes without a p\u2013n junction are often limited in efficiency by charge recombination at semiconductor surfaces and slow charge transfer to electrocatalysts. This study reports that tin oxide (SnO_x) layers applied to n\u2010Si wafers after forming a thin chemically oxidized SiO_x layer can passivate the Si surface while producing \u2248620 mV photovoltage under 100 mW cm^(\u22122) of simulated sunlight. The SnO_x layer makes ohmic contacts to Ni, Ir, or Pt films that act as precatalysts for the oxygen\u2010evolution reaction (OER) in 1.0 m KOH(aq) or 1.0 m H_2SO_4(aq). Ideal regenerative solar\u2010to\u2010O_2(g) efficiencies of 4.1% and 3.7%, respectively, are obtained in 1.0 m KOH(aq) with Ni or in 1.0 m H2_SO_4(aq) with Pt/IrO_x layers as OER catalysts. Stable photocurrents for >100 h are obtained for electrodes with patterned catalyst layers in both 1.0 m KOH(aq) and 1.0 m H_2SO_4(aq).", "date": "2018-08-27", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "8", "number": "24", "publisher": "Wiley", "pagerange": "Art. No. 1801155", "id_number": "CaltechAUTHORS:20180709-131016014", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180709-131016014", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE\u20101144469" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201801155", "primary_object": { "basename": "10.1002:aenm.201801155.pdf", "url": "https://authors.library.caltech.edu/records/kkmk9-n1557/files/10.1002:aenm.201801155.pdf" }, "pub_year": "2018", "author_list": "Moreno-Hernandez, Ivan A.; Brunschwig, Bruce S.; et el." }, { "id": "https://authors.library.caltech.edu/records/r0nhw-jad53", "eprint_id": 89077, "eprint_status": "archive", "datestamp": "2023-08-19 11:11:21", "lastmod": "2023-10-18 22:30:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Jermyn-Adam-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Pala-Ragip-A", "name": { "family": "Pala", "given": "Ragip" } }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Quantifying the role of surface plasmon excitation and hot carrier transport in plasmonic devices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2018. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 08 December 2017; Accepted 11 July 2018; Published 23 August 2018. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. R.S., A.S.J., and P.N. acknowledge support from NG NEXT at Northrop Grumman Corporation. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02\u201305CH11231. A.D. and H.A.A. acknowledge support from the Air Force Office of Scientific Research under grant FA9550-16-1-0019. G.T. acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, grant no. P2EZP2_159101. P.N. acknowledges support from the Harvard University Center for the Environment (HUCE). A.S.J. thanks the UK Marshall Commission and the US Goldwater Scholarship for financial support. A.J.W. acknowledges support from the National Science Foundation (NSF) under Award No. 2016217021. \n\nAuthor Contributions: G.T. performed experiments, numerical simulations, and IQE calculations of devices. A.S.J., R.S., and P.N. performed ab initio hot carrier generation and transport calculations. A.J.W., J.S.D., R.P., and A.R.D. contributed to experiments and data analysis. All authors contributed to interpretation of the results. G.T., J.S.D., A.R.D., and H.A.A. wrote the manuscript with contributions from all authors. H.A.A. supervised all aspects of the project. \n\nThe authors declare no competing interests. \n\nCode availability: First principle methodologies available through open-source software, JDFTx, and post-processing scripts available from authors upon request. \n\nData availability: All relevant data are available from the authors upon request.\n\nPublished - s41467-018-05968-x.pdf
Supplemental Material - 41467_2018_5968_MOESM1_ESM.pdf
", "abstract": "Harnessing photoexcited \"hot\" carriers in metallic nanostructures could define a new phase of non-equilibrium optoelectronics for photodetection and photocatalysis. Surface plasmons are considered pivotal for enabling efficient operation of hot carrier devices. Clarifying the fundamental role of plasmon excitation is therefore critical for exploiting their full potential. Here, we measure the internal quantum efficiency in photoexcited gold (Au)\u2013gallium nitride (GaN) Schottky diodes to elucidate and quantify the distinct roles of surface plasmon excitation, hot carrier transport, and carrier injection in device performance. We show that plasmon excitation does not influence the electronic processes occurring within the hot carrier device. Instead, the metal band structure and carrier transport processes dictate the observed hot carrier photocurrent distribution. The excellent agreement with parameter-free calculations indicates that photoexcited electrons generated in ultra-thin Au nanostructures impinge ballistically on the Au\u2013GaN interface, suggesting the possibility for hot carrier collection without substantial energy losses via thermalization.", "date": "2018-08-23", "date_type": "published", "publication": "Nature Communications", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 3394", "id_number": "CaltechAUTHORS:20180823-080749691", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180823-080749691", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0019" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "Harvard University" }, { "agency": "UK Marshall Commission" }, { "agency": "Barry M. Goldwater Scholarship" }, { "agency": "NSF", "grant_number": "2016217021" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/s41467-018-05968-x", "pmcid": "PMC6107582", "primary_object": { "basename": "41467_2018_5968_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/r0nhw-jad53/files/41467_2018_5968_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "s41467-018-05968-x.pdf", "url": "https://authors.library.caltech.edu/records/r0nhw-jad53/files/s41467-018-05968-x.pdf" } ], "pub_year": "2018", "author_list": "Tagliabue, Giulia; Jermyn, Adam S.; et el." }, { "id": "https://authors.library.caltech.edu/records/778zx-rqb92", "eprint_id": 87092, "eprint_status": "archive", "datestamp": "2023-08-19 11:04:22", "lastmod": "2023-10-18 20:51:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Francis-Sonja-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Ferrer-Ivonne-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Torelli-Daniel-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Hyler-Forrest-P", "name": { "family": "Hyler", "given": "Forrest P." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Reduction of aqueous CO_2 to 1-Propanol at MoS_2 electrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: October 20, 2017; Revised: June 12, 2018; Published: June 13, 2018. \n\nWe thank Dr. Nathan Dalleska and Dr. David VanderVelde of the Environmental Analysis Center and High Resolution NMR Facility, respectively, for many useful discussions and instrumental access and assistance. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. J.M.V. acknowledges support through an NRC Ford Foundation Postdoctoral Fellowship and UC Davis startup funds. D.A.T. acknowledges support through a Graduate Research Fellowship from the National Science Foundation. \n\nAuthor Contributions: S.A.F. and J.M.V. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cm7b04428_si_001.pdf
", "abstract": "Reduction of carbon dioxide in aqueous electrolytes at single-crystal MoS_2 or thin-film MoS_2 electrodes yields 1-propanol as the major CO_2 reduction product, along with hydrogen from water reduction as the predominant reduction process. Lower levels of formate, ethylene glycol, and t-butanol were also produced. At an applied potential of \u22120.59 V versus a reversible hydrogen electrode, the Faradaic efficiencies for reduction of CO_2 to 1-propanol were \u223c3.5% for MoS2single crystals and \u223c1% for thin films with low edge-site densities. Reduction of CO_2 to 1-propanol is a kinetically challenging reaction that requires the overall transfer of 18 e\u2013 and 18 H+ in a process that involves the formation of 2 C\u2013C bonds. NMR analyses using ^(13)CO_2 showed the production of ^(13)C-labeled 1-propanol. In all cases, the vast majority of the Faradaic current resulted in hydrogen evolution via water reduction. H_2S was detected qualitatively when single-crystal MoS_2 electrodes were used, indicating that some desulfidization of single crystals occurred under these conditions.", "date": "2018-08-14", "date_type": "published", "publication": "Chemistry of Materials", "volume": "30", "number": "15", "publisher": "American Chemical Society", "pagerange": "4902-4908", "id_number": "CaltechAUTHORS:20180613-162202390", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180613-162202390", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Research Council" }, { "agency": "Ford Foundation" }, { "agency": "University of California, Davis" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.chemmater.7b04428", "primary_object": { "basename": "cm7b04428_si_001.pdf", "url": "https://authors.library.caltech.edu/records/778zx-rqb92/files/cm7b04428_si_001.pdf" }, "pub_year": "2018", "author_list": "Francis, Sonja A.; Velazquez, Jesus M.; et el." }, { "id": "https://authors.library.caltech.edu/records/xjfy9-eva45", "eprint_id": 87935, "eprint_status": "archive", "datestamp": "2023-08-19 11:02:23", "lastmod": "2023-10-18 21:32:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Comparative Analysis of Solar-to-Fuel Conversion Efficiency: A Direct, One-Step Electrochemical CO_2 Reduction Reactor versus a Two-Step, Cascade Electrochemical CO_2 Reduction Reactor", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: June 26, 2018; Accepted: July 6, 2018; Published: July 17, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.", "abstract": "Electrochemical and photoelectrochemical (PEC) CO_2 reduction (CO_2R) have the potential to produce sustainable, zero greenhouse gas emission fuels and chemicals. One of the key components in a PEC CO2 reduction device is the electrocatalyst materials for the CO_2R reaction. While significant research advances have been made in the development of CO_2 reduction catalysts and in the understanding of the reaction mechanisms, selective, active, and stable catalyst materials have yet to be identified to directly convert CO_2 into higher reduction products, such as ethanol and ethylene. In contrast, several electrocatalyst systems have exhibited promising selectivity and activity for the first two-electron, two-proton process, such as CO_2R to CO or formate. For example, nanostructured silver electrodes, metal dichalcogenides, and single metal atoms in graphene nanosheets exhibited high Faradaic efficiency (FE) and high reaction rates for CO_2R to CO. A Pd/C nanoparticle-based catalyst incorporated in a 10% efficient solar-to-formate conversion device also exhibited near-unity FE at 10s of mA cm^(\u20132) for CO_2R to formate. Hence, one alternative strategy is to leverage the efficient first two-electron, two-proton reaction by using a two-step, cascade CO_2 reactor, in which the first catalytic reactor converts CO_2 into CO or formate and the second catalytic reactor converts CO or formate into higher-order reduction products such as ethanol or ethylene. Herein, the solar-to-fuel (STF) conversion efficiencies in a direct, one-step CO2reduction reactor and a two-step, cascade CO_2 reduction reactor were analyzed and compared for two distinctive device configurations.", "date": "2018-08-10", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "8", "publisher": "American Chemical Society", "pagerange": "1892-1897", "id_number": "CaltechAUTHORS:20180717-144513102", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180717-144513102", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b01077", "pub_year": "2018", "author_list": "Zhou, Xinghao and Xiang, Chengxiang" }, { "id": "https://authors.library.caltech.edu/records/v95rs-72g60", "eprint_id": 79579, "eprint_status": "archive", "datestamp": "2023-08-19 11:02:08", "lastmod": "2023-10-26 16:57:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "May-Matthias-M", "name": { "family": "May", "given": "Matthias M." }, "orcid": "0000-0002-1252-806X" }, { "id": "Ohlmann-Jens", "name": { "family": "Ohlmann", "given": "Jens" }, "orcid": "0000-0003-3229-1482" }, { "id": "Lackner-David", "name": { "family": "Lackner", "given": "David" }, "orcid": "0000-0001-8170-0874" }, { "id": "Dimroth-Frank", "name": { "family": "Dimroth", "given": "Frank" }, "orcid": "0000-0002-3615-4437" }, { "id": "Hannappel-Thomas", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Monolithic Photoelectrochemical Device for 19% Direct Water Splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: June 2, 2018; Accepted: June 25, 2018; Published: June 25, 2018. \n\nThe authors acknowledge Katherine T. Fountaine for the calculation of theoretical photocurrent efficiencies of 2J PEC devices. This work was supported through the Office of Science of the U.S. Department of Energy (DOE) under Award No. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. The work on tandem absorbers was funded by the German Federal Ministry of Education and research (BMBF) under Contract Number FKZ 03F0432A (HyCon). M.M.M. acknowledges funding from the fellowship programme of the German National Academy of Sciences Leopoldina, Grant LPDS 2015-09. \n\nAuthor Contributions: T.H., H.J.L, M.M.M., W.H.C., M.H.R. and H.A.A. conceived of the experimental study. W.H.C. and M.H.R. executed the experiments and did the data analysis. J.O., D.L., and F.D. prepared the tandem absorber. W.H.C., M.H.R., H.J.L., and H.A.A. wrote the paper, and all authors commented on the manuscript. \n\nThe authors declare no competing financial interest.\n\nSubmitted - 1706.01493.pdf
Supplemental Material - nz8b00920_si_001.pdf
", "abstract": "Efficient unassisted solar water splitting, a pathway to storable renewable energy in the form of chemical bonds, requires optimization of a photoelectrochemical device based on photovoltaic tandem heterojunctions. We report a monolithic photocathode device architecture that exhibits significantly reduced surface reflectivity, minimizing parasitic light absorption and reflection losses. A tailored multifunctional crystalline titania interphase layer acts as a corrosion protection layer, with favorable band alignment between the semiconductor conduction band and the energy level for water reduction, facilitating electron transport at the cathode\u2013electrolyte interface. It also provides a favorable substrate for adhesion of high-activity Rh catalyst nanoparticles. Under simulated AM 1.5G irradiation, solar-to-hydrogen efficiencies of 19.3 and 18.5% are obtained in acidic and neutral electrolytes, respectively. The system reaches a value of 0.85 of the theoretical limit for photoelectrochemical water splitting for the energy gap combination employed in the tandem-junction photoelectrode structure.", "date": "2018-08-10", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "8", "publisher": "American Chemical Society", "pagerange": "1795-1800", "id_number": "CaltechAUTHORS:20170731-084813550", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170731-084813550", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "FKZ 03F0432A" }, { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2015-09" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b00920", "primary_object": { "basename": "1706.01493.pdf", "url": "https://authors.library.caltech.edu/records/v95rs-72g60/files/1706.01493.pdf" }, "related_objects": [ { "basename": "nz8b00920_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v95rs-72g60/files/nz8b00920_si_001.pdf" } ], "pub_year": "2018", "author_list": "Cheng, Wen-Hui; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/8cg4q-az015", "eprint_id": 87870, "eprint_status": "archive", "datestamp": "2023-08-19 10:55:47", "lastmod": "2023-10-18 21:30:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lum-Yanwei", "name": { "family": "Lum", "given": "Yanwei" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Ager-J-W", "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" } ] }, "title": "Electrochemical CO reduction builds solvent water into oxygenate products", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: April 13, 2018; Published: July 16, 2018. \nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. Y.L. acknowledges the support of an A*STAR National Science Scholarship. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1548562. We thank Lingfei Wei for assistance with technical illustrations. \n\nAuthor Contributions: Y.L. and T.C. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b03986_si_001.pdf
Supplemental Material - ja8b03986_si_002.mpg
", "abstract": "Numerous studies have examined the electrochemical reduction of CO (COR) to oxygenates (e.g., ethanol). None have considered the possibility that oxygen in the product might arise from water rather than from CO. To test this assumption, C^(16)O reduction was performed in H_2^(18)O electrolyte. Surprisingly, we found that 60\u201370% of the ethanol contained 18O, which must have originated from the solvent. We extended our previous all-solvent density functional theory metadynamics calculations to consider the possibility of incorporating water, and indeed, we found a new mechanism involving a Grotthuss chain of six water molecules in a concerted reaction with the *C\u2013CH intermediate to form *CH\u2013CH(^(18)OH), subsequently leading to (^(18)O)ethanol. This competes with the formation of ethylene that also arises from *C\u2013CH. These unforeseen results suggest that all previous studies of COR under aqueous conditions must be reexamined.", "date": "2018-08-01", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "30", "publisher": "American Chemical Society", "pagerange": "9337-9340", "id_number": "CaltechAUTHORS:20180716-093223969", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180716-093223969", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Agency for Science, Technology and Research (A*STAR)" }, { "agency": "NSF", "grant_number": "ACI-1548562" } ] }, "other_numbering_system": { "items": [ { "id": "1291", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b03986", "primary_object": { "basename": "ja8b03986_si_001.pdf", "url": "https://authors.library.caltech.edu/records/8cg4q-az015/files/ja8b03986_si_001.pdf" }, "related_objects": [ { "basename": "ja8b03986_si_002.mpg", "url": "https://authors.library.caltech.edu/records/8cg4q-az015/files/ja8b03986_si_002.mpg" } ], "pub_year": "2018", "author_list": "Lum, Yanwei; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/0wnhk-9qh81", "eprint_id": 86585, "eprint_status": "archive", "datestamp": "2023-08-19 10:55:24", "lastmod": "2023-10-18 19:45:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brinkert-K", "name": { "family": "Brinkert", "given": "Katharina" }, "orcid": "0000-0002-3593-5047" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Akay-\u00d6", "name": { "family": "Akay", "given": "\u00d6mer" } }, { "id": "Giersig-M", "name": { "family": "Giersig", "given": "Michael" } }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Advancing semiconductor\u2013electrocatalyst systems: application of surface transformation films and nanosphere lithography", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 12 Jan 2018, accepted on 05 Mar 2018 and first published on 05 Mar 2018. \n\nK. B. acknowledges funding from the fellowship program of the German National Academy of Sciences Leopoldina, grant LPDS 2016-06. Furthermore, she would like to thank Prof. Harry B. Gray for his great support. Research was in part carried out at the Joint Center for Artificial Photosynthesis, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. M. H. R. and K. B. would like to acknowledge support from the Beckman Institute of the California Institute of Technology and the Molecular Materials Research Center. \n\nThe authors declare no conflicts of interest.", "abstract": "Photoelectrochemical (PEC) cells offer the possibility of carbon-neutral solar fuel production through artificial photosynthesis. The pursued design involves technologically advanced III\u2013V semiconductor absorbers coupled via an interfacial film to an electrocatalyst layer. These systems have been prepared by in situ surface transformations in electrochemical environments. High activity nanostructured electrocatalysts are required for an efficiently operating cell, optimized in their optical and electrical properties. We demonstrate that shadow nanosphere lithography (SNL) is an auspicious tool to systematically create three-dimensional electrocatalyst nanostructures on the semiconductor photoelectrode through controlling their morphology and optical properties. First results are demonstrated by means of the photoelectrochemical production of hydrogen on p-type InP photocathodes where hitherto applied photoelectrodeposition and SNL-deposited Rh electrocatalysts are compared based on their J\u2013V and spectroscopic behavior. We show that smaller polystyrene particle masks achieve higher defect nanostructures of rhodium on the photoelectrode which leads to a higher catalytic activity and larger short circuit currents. Structural analyses including HRSEM and the analysis of the photoelectrode surface composition by using photoelectron spectroscopy support and complement the photoelectrochemical observations. The optical performance is further compared to theoretical models of the nanostructured photoelectrodes on light scattering and propagation.", "date": "2018-08-01", "date_type": "published", "publication": "Faraday Discussions", "volume": "208", "publisher": "Royal Society of Chemistry", "pagerange": "523-535", "id_number": "CaltechAUTHORS:20180524-095254711", "issn": "1359-6640", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180524-095254711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2016-06" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c8fd00003d", "pub_year": "2018", "author_list": "Brinkert, Katharina; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/tst3n-c6980", "eprint_id": 87277, "eprint_status": "archive", "datestamp": "2023-08-19 10:35:16", "lastmod": "2023-10-18 21:00:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Swabeck-J-K", "name": { "family": "Swabeck", "given": "Joseph K." }, "orcid": "0000-0003-2235-2472" }, { "id": "Fischer-S", "name": { "family": "Fischer", "given": "Stefan" }, "orcid": "0000-0003-4110-6576" }, { "id": "Bronstein-N-D", "name": { "family": "Bronstein", "given": "Noah D." }, "orcid": "0000-0003-3657-2652" }, { "id": "Alivisatos-A-P", "name": { "family": "Alivisatos", "given": "A. Paul" }, "orcid": "0000-0001-6895-9048" } ] }, "title": "Broadband sensitization of lanthanide emission with indium phosphide quantum dots for visible to NIR downshifting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: March 12, 2018; Published: June 20, 2018. \n\nThe authors thank Brent Koscher for general advice and Matthew Marcus and Sirine Fakra of ALS beamline 10.3.2 for help with EXAFS measurements. The work was supported by the Light-Material Interactions in Energy Conversion, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract DE-AC02-05CH11231, part of the EFRC at Caltech under DE-SC0001293. Work at the Molecular Foundry was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-05CH11231. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b02612_si_001.pdf
", "abstract": "Semiconductor quantum dot (QD)-sensitized lanthanide ions hold great promise in producing a broadly absorbing and sharply emitting luminophore, but their synthesis has proven to be difficult. We report the first synthesis of core/shell/shell InP/Ln_xY_(1\u2013x)F_3/ShF_3 (Ln = Yb, Nd; Sh = Lu, Y) nanocrystals that exhibit a broad visible absorption coupled to a sharp near-infrared emission. Additionally, this is the first report of Nd being coupled to a QD absorber. We characterize the system with a variety of electron microscopy and X-ray techniques that prove this unique structure. Optical measurements confirm the correlation of the Ln^(3+) emission to the QD absorption, while the presence of a trap-state emission gives a clue as to the mechanism of energy transfer between the dot and the lanthanide.", "date": "2018-07-25", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "29", "publisher": "American Chemical Society", "pagerange": "9120-9126", "id_number": "CaltechAUTHORS:20180620-153421260", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180620-153421260", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b02612", "primary_object": { "basename": "ja8b02612_si_001.pdf", "url": "https://authors.library.caltech.edu/records/tst3n-c6980/files/ja8b02612_si_001.pdf" }, "pub_year": "2018", "author_list": "Swabeck, Joseph K.; Fischer, Stefan; et el." }, { "id": "https://authors.library.caltech.edu/records/cvp59-p5e83", "eprint_id": 87681, "eprint_status": "archive", "datestamp": "2023-08-21 23:40:08", "lastmod": "2023-10-18 21:21:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brinkert-Katharina", "name": { "family": "Brinkert", "given": "Katharina" }, "orcid": "0000-0002-3593-5047" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Akay-\u00d6mer", "name": { "family": "Akay", "given": "\u00d6mer" } }, { "id": "Liedtke-Janine", "name": { "family": "Liedtke", "given": "Janine" }, "orcid": "0000-0003-2680-4130" }, { "id": "Giersig-Michael", "name": { "family": "Giersig", "given": "Michael" } }, { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Efficient solar hydrogen generation in microgravity environment", "ispublished": "pub", "full_text_status": "public", "keywords": "Chemical engineering; Electrocatalysis; Nanoscale materials; Photocatalysis; Solar fuels", "note": "\u00a9 The Author(s) 2018. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 07 March 2018; Accepted 23 May 2018; Published 10 July 2018. \n\nK.B. acknowledges funding from the fellowship programme of the German National Academy of Sciences Leopoldina, grant LPDS 2016-06 and the European Space Agency. Furthermore, she would like to thank Dr. Leopold Summerer, the Advanced Concepts Team, Alan Dowson, Dr. Jack van Loon, Dr. Gabor Milassin, Marcel van Slogteren and Dr. Robert Lindner (ESTEC), Robbert-Jan Noordam (Notese) and Prof. Harry B. Gray (Caltech) for their great support. M.H.R. is grateful for generous support from Prof. Nathan S. Lewis (Caltech). K.B. and M.H.R. acknowledge support from the Beckman Institute of the California Institute of Technology and the Molecular Materials Research Center. M.G. acknowledges funding from the Guangdong Innovative and Entrepreneurial Team Program titled 'Plasmonic Nanomaterials and Quantum Dots for Light Management in Optoelectronic Devices' (No. 2016ZT06C517). Furthermore, the author team greatly acknowledges the effort and support from the ZARM Team with Dr. Thorben K\u00f6nemann and Dr. Martin Castillo at the Bremen Drop Tower. It is also thankful for enlightening discussions with Prof. Yasuhiro Fukunaka (Waseda University), Prof. Hisayoshi Matsushima (Hokkaido University) and Dr. Slobodan Mitrovic (Lam Research). The team would also like to thank Dr. Eser Metin Akinoglu from the International Academy of Optoelectronics, Zhaoqing, for his help with the SEM characterization of the samples and Dr. Axel Knop-Gericke (Fritz Haber Institute of the Max Planck Society) for his generous help with XPS measurements. \n\nAuthor Contributions: K.B., M.H.R., J.L. and H.-J.L. planned and carried out the terrestrial experiments and the experiments at the Bremen Drop Tower. \u00d6.A., K.B. and J.L. prepared the nanostructured photoelectrodes under the supervision of M.G. and H.-J.L. K.T.F. carried out the theoretical calculations and simulations. K.B., H.-J.L and K.T.F. wrote the manuscript which is approved by all authors. \n\nThe authors declare no competing interests. \n\nData availability: All relevant data are available from the authors upon request.\n\nPublished - s41467-018-04844-y.pdf
Supplemental Material - 41467_2018_4844_MOESM1_ESM.pdf
Supplemental Material - 41467_2018_4844_MOESM2_ESM.pdf
", "abstract": "Long-term space missions require extra-terrestrial production of storable, renewable energy. Hydrogen is ascribed a crucial role for transportation, electrical power and oxygen generation. We demonstrate in a series of drop tower experiments that efficient direct hydrogen production can be realized photoelectrochemically in microgravity environment, providing an alternative route to existing life support technologies for space travel. The photoelectrochemical cell consists of an integrated catalyst-functionalized semiconductor system that generates hydrogen with current densities >15\u2009mA/cm^2 in the absence of buoyancy. Conditions are described adverting the resulting formation of ion transport blocking froth layers on the photoelectrodes. The current limiting factors were overcome by controlling the micro- and nanotopography of the Rh electrocatalyst using shadow nanosphere lithography. The behaviour of the applied system in terrestrial and microgravity environment is simulated using a kinetic transport model. Differences observed for varied catalyst topography are elucidated, enabling future photoelectrode designs for use in reduced gravity environments.", "date": "2018-07-10", "date_type": "published", "publication": "Nature Communications", "volume": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 2527", "id_number": "CaltechAUTHORS:20180710-080707049", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180710-080707049", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Akademie der Naturforscher Leopoldina", "grant_number": "LPDS 2016-06" }, { "agency": "European Space Agency (ESA)" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Guangdong Innovative and Entrepreneurial Team Program", "grant_number": "2016ZT06C517" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1038/s41467-018-04844-y", "pmcid": "PMC6039473", "primary_object": { "basename": "41467_2018_4844_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/41467_2018_4844_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2018_4844_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/41467_2018_4844_MOESM2_ESM.pdf" }, { "basename": "s41467-018-04844-y.pdf", "url": "https://authors.library.caltech.edu/records/cvp59-p5e83/files/s41467-018-04844-y.pdf" } ], "pub_year": "2018", "author_list": "Brinkert, Katharina; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/c6jzb-hyr61", "eprint_id": 86790, "eprint_status": "archive", "datestamp": "2023-08-19 10:13:06", "lastmod": "2023-10-18 20:35:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Clark-E-L", "name": { "family": "Clark", "given": "Ezra L." } }, { "id": "Resasco-J", "name": { "family": "Resasco", "given": "Joaquin" } }, { "id": "Landers-A-T", "name": { "family": "Landers", "given": "Alan" } }, { "id": "Lin-John", "name": { "family": "Lin", "given": "John" } }, { "id": "Chung-Linh-Thao", "name": { "family": "Chung", "given": "Linh-Thao" } }, { "id": "Walton-A", "name": { "family": "Walton", "given": "Amber" } }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" }, { "id": "Bell-A-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" } ] }, "title": "Data Acquisition Protocols and Reporting Standards for Studies of the Electrochemical Reduction of Carbon Dioxide", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrocatalysis, CO2 reduction, experimental protocols, catalyst benchmarking, mass transfer effects, surface contamination, surface area normalization, intrinsic activity metrics", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: April 5, 2018; Revised: May 30, 2018; Published: June 1, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. E.L.C. and J.R. were supported by the National Science Foundation (NSF). \n\nAuthor Contributions: E.L.C. and J.R. contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs8b01340_si_001.pdf
", "abstract": "Objective evaluation of the performance of electrocatalysts for CO_2 reduction has been complicated by a lack of standardized methods for measuring and reporting activity data. In this perspective, we advocate that standardizing these practices can aid in advancing research efforts toward the development of efficient and selective CO_2 reduction electrocatalysts. Using information taken from experimental studies, we identify variables that influence the measured activity of CO_2 reduction electrocatalysts and propose procedures to account for these variables in order to improve the accuracy and reproducibility of reported data. We recommend that catalysts be measured under conditions which do not introduce artifacts from impurities, from either the electrolyte or counter electrode, and advocate the acquisition of data measured in the absence of mass transport effects. Furthermore, measured rates of electrochemical reactions should be normalized to both the geometric electrode area as well as the electrochemically active surface area to facilitate the comparison of reported catalysts with those previously known. We demonstrate that, when these factors are accounted for, the CO_2 reduction activities of Ag and Cu measured in different laboratories exhibit little difference. Adoption of the recommendations presented in this perspective would greatly facilitate the identification of superior catalysts for CO_2 reduction arising solely from changes in their composition and pretreatment.", "date": "2018-07-06", "date_type": "published", "publication": "ACS Catalysis", "volume": "8", "number": "7", "publisher": "American Chemical Society", "pagerange": "6560-6570", "id_number": "CaltechAUTHORS:20180604-132638553", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180604-132638553", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.8b01340", "primary_object": { "basename": "cs8b01340_si_001.pdf", "url": "https://authors.library.caltech.edu/records/c6jzb-hyr61/files/cs8b01340_si_001.pdf" }, "pub_year": "2018", "author_list": "Clark, Ezra L.; Resasco, Joaquin; et el." }, { "id": "https://authors.library.caltech.edu/records/m9zx6-33s73", "eprint_id": 85742, "eprint_status": "archive", "datestamp": "2023-08-21 23:35:02", "lastmod": "2023-10-18 18:44:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Surface Reconstruction of Polycrystalline Cu Electrodes in Aqueous KHCO_3 Electrolyte at Potentials in the Early Stages of CO_2 Reduction", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Surface reconstruction of Cu(pc) under CO2-reduction potentials; Operando electrochemical scanning tunneling microscopy; Electrochemical CO2 reduction; Cu(pc) to Cu(pc)-[Cu(100)] surface reconstruction", "note": "\u00a9 2018 Springer Science+Business Media, LLC, part of Springer Nature. \n\nFirst Online: 06 April 2018. \n\nThis material is based upon the work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993.", "abstract": "The reconstruction of the Cu(pc) polycrystalline surface at potentials that correspond to the early stages of CO_2 reduction in 0.1 M KHCO_3 was investigated by electrochemical scanning tunneling microscopy (ECSTM) at \u22120.90 V (SHE). A kinetically hindered surface reconstruction of the topmost layers of Cu(pc) into the (100) face was observed, reminiscent of the transformation previously reported at the same electrode potential in 0.1 M KOH. Evidently, the same reconstructed surface, Cu(pc)-[Cu(100)], can be generated in either 0.1 M KHCO_3 (pH 8) or 0.1 M KOH (pH 13). In addition, only minimal structural disruption was observed when the reconstructed surface was transferred from KHCO_3 to KOH electrolyte, and vice versa, provided the solution exchange was executed potentiostatically at \u22120.90 V. The structural convergence toward the same (100) facet regardless of pH or supporting electrolyte strongly suggests that the Cu(pc)\u2009\u2192\u2009Cu(pc)-[Cu(100)] surface reorganization is a general phenomenon driven primarily by the rather negative potential applied on the electrode.", "date": "2018-07", "date_type": "published", "publication": "Electrocatalysis", "volume": "9", "number": "4", "publisher": "Springer", "pagerange": "526-530", "id_number": "CaltechAUTHORS:20180411-084932076", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180411-084932076", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-018-0469-z", "pub_year": "2018", "author_list": "Kim, Youn-Geun; Baricuatro, Jack H.; et el." }, { "id": "https://authors.library.caltech.edu/records/se0c1-zh578", "eprint_id": 86586, "eprint_status": "archive", "datestamp": "2023-08-19 09:55:04", "lastmod": "2023-10-18 19:45:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Wang-Lu", "name": { "family": "Wang", "given": "Lu" }, "orcid": "0000-0001-5263-3123" }, { "id": "Merinov-B-V", "name": { "family": "Merinov", "given": "Boris V." }, "orcid": "0000-0002-2783-4262" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Explanation of Dramatic pH-Dependence of Hydrogen Binding on Noble Metal Electrode: Greatly Weakened Water Adsorption at High pH", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: April 22, 2018; Published: May 24, 2018. \n\nThis work was initiated with support from National Science Foundation (CBET 1512759, program manager Robert McCabe) and completed with support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1053575. \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - ja8b04006_si_001.pdf
", "abstract": "Hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) are both 2 orders slower in alkaline electrolyte than in acidic electrolyte, but no explanation has been provided. The first step toward understanding this dramatic pH-dependent HOR/HER performance is to explain the pH-dependent hydrogen binding to the electrode, a perplexing behavior observed experimentally. In this work, we carried out Quantum Mechanics Molecular Dynamics (QMMD) with explicit considerations of solvent and applied voltage (U) to in situ simulate water/Pt(100) interface in the condition of under-potential adsorption of hydrogen (H_(UPD)). We found that as U is made more negative, the electrode tends to repel water, which in turn increases the hydrogen binding. We predicted a 0.13 eV increase in hydrogen binding from pH = 0.2 to pH = 12.8 with a slope of 10 meV/pH, which is close to the experimental observation of 8 to 12 meV/pH. Thus, we conclude that the changes in water adsorption are the major causes of pH-dependent hydrogen binding on a noble metal. The new insight of critical role of surface water in modifying electrochemical reactions provides a guideline in designing HER/HOR catalyst targeting for the alkaline electrolyte.", "date": "2018-06-27", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "25", "publisher": "American Chemical Society", "pagerange": "7787-7790", "id_number": "CaltechAUTHORS:20180524-100856381", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180524-100856381", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1278", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b04006", "primary_object": { "basename": "ja8b04006_si_001.pdf", "url": "https://authors.library.caltech.edu/records/se0c1-zh578/files/ja8b04006_si_001.pdf" }, "pub_year": "2018", "author_list": "Cheng, Tao; Wang, Lu; et el." }, { "id": "https://authors.library.caltech.edu/records/tpre5-hge40", "eprint_id": 86732, "eprint_status": "archive", "datestamp": "2023-08-19 09:44:38", "lastmod": "2023-10-18 19:56:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Landers-A-T", "name": { "family": "Landers", "given": "Alan T." } }, { "id": "Fields-M", "name": { "family": "Fields", "given": "Meredith" } }, { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Xiao-Jianping", "name": { "family": "Xiao", "given": "Jianping" }, "orcid": "0000-0003-1779-6140" }, { "id": "Hellstern-T-R", "name": { "family": "Hellstern", "given": "Thomas R." } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Tsai-Charlie", "name": { "family": "Tsai", "given": "Charlie" } }, { "id": "Kibsgaard-J", "name": { "family": "Kibsgaard", "given": "Jakob" }, "orcid": "0000-0002-9219-816X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "The Predominance of Hydrogen Evolution on Transition Metal Sulfides and Phosphides under CO_2 Reduction Conditions: An Experimental and Theoretical Study", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 9, 2018; Accepted: April 20, 2018; Publication Date (Web): May 31, 2018. \n\nThis material is based, in part, on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy, under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy (under Contract No. DE-AC02-05CH11231). Part of this work was performed at the Stanford Nano Shared Facilities (SNSF) and the Stanford Nanofabrication Facility (SNF), supported by the National Science Foundation under Award ECCS-1542152. We also acknowledge assistance from the Stanford NMR Facility. M.F. and D.A.T. acknowledge a graduate fellowship through the National Science Foundation. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a postdoctoral fellowship. The authors also thank J. Chance Crompton for assistance in synthesizing the nanoparticle electrocatalysts. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz8b00237_si_001.pdf
", "abstract": "A combination of experiment and theory has been used to understand the relationship between the hydrogen evolution reaction (HER) and CO_2 reduction (CO_2R) on transition metal phosphide and transition metal sulfide catalysts. Although multifunctional active sites in these materials could potentially improve their CO_2R activity relative to pure transition metal electrocatalysts, under aqueous testing conditions, these materials showed a high selectivity for the HER relative to CO_2R. Computational results supported these findings, indicating that a limitation of the metal phosphide catalysts is that the HER is favored thermodynamically over CO_2R. On Ni-MoS_2, a limitation is the kinetic barrier for the proton\u2013electron transfer to *CO. These theoretical and experimental results demonstrate that selective CO_2R requires electrocatalysts that possess both favorable thermodynamic pathways and surmountable kinetic barriers.", "date": "2018-06-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "6", "publisher": "American Chemical Society", "pagerange": "1450-1457", "id_number": "CaltechAUTHORS:20180601-080239556", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180601-080239556", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ECCS-1542152" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acsenergylett.8b00237", "primary_object": { "basename": "nz8b00237_si_001.pdf", "url": "https://authors.library.caltech.edu/records/tpre5-hge40/files/nz8b00237_si_001.pdf" }, "pub_year": "2018", "author_list": "Landers, Alan T.; Fields, Meredith; et el." }, { "id": "https://authors.library.caltech.edu/records/0swra-cbg89", "eprint_id": 86542, "eprint_status": "archive", "datestamp": "2023-08-19 09:43:13", "lastmod": "2023-10-18 19:42:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Zhijiang", "name": { "family": "Wang", "given": "Zhijiang" }, "orcid": "0000-0001-9314-7922" }, { "id": "Wu-Lina", "name": { "family": "Wu", "given": "Lina" } }, { "id": "Sun-Kun", "name": { "family": "Sun", "given": "Kun" } }, { "id": "Chen-Ting", "name": { "family": "Chen", "given": "Ting" }, "orcid": "0000-0002-9599-871X" }, { "id": "Jiang-Zhaohua", "name": { "family": "Jiang", "given": "Zhaohua" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Surface Ligand Promotion of Carbon Dioxide Reduction through Stabilizing Chemisorbed Reactive Intermediates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: March 28, 2018; Accepted: May 22, 2018; Published: May 22, 2018. \n\nT.C. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation Grant Number ACI-1053575. Z.W. acknowledges financial support from the Open Project of State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology (No. HC201813). L.W. acknowledges financial support from the National Natural Science Foundation of China (No. 81771903) and Wuliande Foundation of Harbin Medical University (No. WLD-QN1404). \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - jz8b00959_si_001.pdf
", "abstract": "We have explored functionalizing metal catalysts with surface ligands as an approach to facilitate electrochemical carbon dioxide reduction reaction (CO_2RR). To provide a molecular level understanding of the mechanism by which this enhancement occurs, we combine in situ spectroscopy analysis with an interpretation based on quantum mechanics (QM) calculations. We find that a surface ligand can play a critical role in stabilizing the chemisorbed CO_2, which facilitates CO_2 activation and leads to a 0.3 V decrease in the overpotential for carbon monoxide (CO) formation. Moreover, the presence of the surface ligand leads to nearly exclusive CO production. At \u22120.6 V (versus reversible hydrogen electrode, RHE), CO is the only significant product with a faradic efficiency of 93% and a current density of 1.9 mA cm^(\u20132). This improvement corresponds to 53-fold enhancement in turnover frequency compared with the Ag nanoparticles (NPs) without surface ligands.", "date": "2018-06-07", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "9", "number": "11", "publisher": "American Chemical Society", "pagerange": "3057-3061", "id_number": "CaltechAUTHORS:20180522-100408414", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180522-100408414", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "State Key Laboratory of Urban Water Resource and Environment" }, { "agency": "Harbin Institute of Technology", "grant_number": "HC201813" }, { "agency": "National Natural Science Foundation of China", "grant_number": "81771903" }, { "agency": "Wuliande Foundation of Harbin Medical University", "grant_number": "WLD-QN1404" } ] }, "other_numbering_system": { "items": [ { "id": "1285", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.8b00959", "primary_object": { "basename": "jz8b00959_si_001.pdf", "url": "https://authors.library.caltech.edu/records/0swra-cbg89/files/jz8b00959_si_001.pdf" }, "pub_year": "2018", "author_list": "Wang, Zhijiang; Wu, Lina; et el." }, { "id": "https://authors.library.caltech.edu/records/jp5z6-4rn48", "eprint_id": 86362, "eprint_status": "archive", "datestamp": "2023-08-19 09:42:55", "lastmod": "2023-10-18 19:31:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shin-Hyeyoung", "name": { "family": "Shin", "given": "Hyeyoung" }, "orcid": "0000-0001-6694-7895" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "In silico discovery of new dopants for Fe-doped Ni oxyhydroxide (Ni_(1-x)Fe_xOOH) catalysts for oxygen evolution reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: February 25, 2018; Published: May 11, 2018. \n\nThis work was supported by the JCAP, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The quantum mechanics (QM) calculations used the resources of the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation grant number ACI-1053575. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja8b02225_si_001.pdf
", "abstract": "The oxygen evolution reaction (OER) is critical to efficient water splitting to produce the H_2 fuel for sustainable energy production. Currently, the best non-noble metal OER electrocatalyst in base conditions is the Fe-doped NiOOH (Ni_(1\u2013x)Fe_xOOH), with an overpotential of \u03b7 = 0.4, but much lower values are desired. We use density functional theory to determine the overall mechanism for the OER of Ni_(1\u2013x)Fe_xOOH, concluding that promoting radical character on the metal\u2013oxo bond is critical to efficient OER. Then we consider replacing Fe with 17 other transition metals of the Fe, Ru, and Os rows, where we find 3 new promising candidates: Co, Rh, and Ir, which we estimate to have \u03b7 = 0.27, 0.15, and 0.02, respectively, all very much improved performance compared to Fe, making all three systems excellent candidates for experimental testing.", "date": "2018-06-06", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "22", "publisher": "American Chemical Society", "pagerange": "6745-6748", "id_number": "CaltechAUTHORS:20180511-100334050", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180511-100334050", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1284", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.8b02225", "primary_object": { "basename": "ja8b02225_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jp5z6-4rn48/files/ja8b02225_si_001.pdf" }, "pub_year": "2018", "author_list": "Shin, Hyeyoung; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/h75ng-68197", "eprint_id": 86530, "eprint_status": "archive", "datestamp": "2023-08-21 23:30:10", "lastmod": "2023-10-18 19:41:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Shin-Hyeyoung", "name": { "family": "Shin", "given": "Hyeyoung" }, "orcid": "0000-0001-6694-7895" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Synergy between Fe and Ni in the optimal performance of (Ni,Fe)OOH catalysts for the oxygen evolution reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "density functional theory; B3PW91; PBE; electrocatalysis; reaction mechanism", "note": "\u00a9 2018 National Academy of Sciences. Published under the PNAS license. \n\nContributed by William A. Goddard III, April 14, 2018 (sent for review December 18, 2017; reviewed by Daniel G. Nocera and Annabella Selloni) PNAS May 21, 2018. 201722034; published ahead of print May 21, 2018. https://doi.org/10.1073/pnas.1722034115 \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE under Award DE-SC0004993. The calculations were carried out on the Extreme Science and Engineering Discovery Environment, which is supported by National Science Foundation Grant ACI-1053575, and the Zwicky Astrophysics Supercomputer at Caltech. \n\nAuthor contributions: H.X. and W.A.G. designed research; H.X. and H.S. performed research; H.X. and H.S. analyzed data; and H.X. and W.A.G. wrote the paper. \n\nReviewers: D.G.N., Harvard University; and A.S., Princeton University. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1722034115/-/DCSupplemental.\n\nPublished - 5872.full.pdf
Supplemental Material - pnas.1722034115.sapp.pdf
", "abstract": "The oxygen evolution reaction (OER) is critical to solar production of fuels, but the reaction mechanism underlying the performance for a best OER catalyst, Fe-doped NiOOH [(Ni,Fe)OOH], remains highly controversial. We used grand canonical quantum mechanics to predict the OER mechanisms including kinetics and thus overpotentials as a function of Fe content in (Ni,Fe)OOH catalysts. We find that density functional theory (DFT) without exact exchange predicts that addition of Fe does not reduce the overpotential much. However, DFT with exact exchange predicts dramatic improvement in performance for (Ni,Fe)OOH, leading to an overpotential of 0.42 V and a Tafel slope of 23 mV/decade (dec), in good agreement with experiments, 0.3\u20130.4 V and 30 mV/dec. We reveal that the high spin d^4 Fe(IV) leads to efficient formation of an active O radical intermediate, while the closed shell d^6 Ni(IV) catalyzes the subsequent O\u2013O coupling, and thus it is the synergy between Fe and Ni that delivers the optimal performance for OER.", "date": "2018-06-05", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "115", "number": "23", "publisher": "National Academy of Sciences", "pagerange": "5872-5877", "id_number": "CaltechAUTHORS:20180521-155521778", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180521-155521778", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "other_numbering_system": { "items": [ { "id": "1286", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1722034115", "pmcid": "PMC6003342", "primary_object": { "basename": "5872.full.pdf", "url": "https://authors.library.caltech.edu/records/h75ng-68197/files/5872.full.pdf" }, "related_objects": [ { "basename": "pnas.1722034115.sapp.pdf", "url": "https://authors.library.caltech.edu/records/h75ng-68197/files/pnas.1722034115.sapp.pdf" } ], "pub_year": "2018", "author_list": "Xiao, Hai; Shin, Hyeyoung; et el." }, { "id": "https://authors.library.caltech.edu/records/q78n6-4q891", "eprint_id": 86044, "eprint_status": "archive", "datestamp": "2023-08-21 23:26:01", "lastmod": "2023-10-18 19:12:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Korzeniewski-Carol-L", "name": { "family": "Korzeniewski", "given": "Carol L." }, "orcid": "0000-0003-3672-0731" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Seriatim ECSTM-ECPMIRS of the adsorption of carbon monoxide on Cu(100) in alkaline solution at CO_2-reduction potentials", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Seriatim ECSTM-ECPMIRS; Operando electrode-surface nanoscopy; Operando molecular vibrational spectroscopy; Potential-dependent CO adsorption on Cu(100); Electrochemical reduction of CO2 in alkaline solution", "note": "\u00a9 2018 Elsevier. \n\nReceived 11 March 2018; Received in revised form 18 April 2018; Accepted 20 April 2018. Available online 22 April 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "It was recently demonstrated that the sequential or seriatim application of electrochemical scanning tunneling microscopy (ECSTM) and differential electrochemical mass spectrometry (DEMS) enables the correlation, under actual reaction conditions, of a specific structure on a Cu electrode surface with the generation of a particular CO-reduction product. As an extension of the operando hyphenated-technique approach, we paired ECSTM with electrochemical polarization-modulation IR reflection-absorption spectroscopy (ECPMIRS) to identify a delineating potential that affected the coverage, the molecular orientation, and the adlattice structure of CO adsorbed on Cu(100) in 0.1\u202fM KOH under CO_2-reduction conditions. The results may have significant ramifications on the theory-based reaction mechanism for the formation of C_2 compounds, as well as insights into the mode of coordination between CO and zerovalent Cu.", "date": "2018-06", "date_type": "published", "publication": "Electrochemistry Communications", "volume": "91", "publisher": "Elsevier", "pagerange": "1-4", "id_number": "CaltechAUTHORS:20180425-144714864", "issn": "1388-2481", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180425-144714864", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.elecom.2018.04.016", "pub_year": "2018", "author_list": "Baricuatro, Jack H.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/3fh0x-7q045", "eprint_id": 89027, "eprint_status": "archive", "datestamp": "2023-08-19 09:20:31", "lastmod": "2023-10-18 22:27:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Banerjee-S", "name": { "family": "Banerjee", "given": "Sriya" } }, { "id": "Wu-Fei", "name": { "family": "Wu", "given": "Fei" } }, { "id": "Myung-Yoon", "name": { "family": "Myung", "given": "Yoon" } }, { "id": "Chatman-S-M", "name": { "family": "Chatman", "given": "Shawn" }, "orcid": "0000-0002-7951-5968" }, { "id": "Niedzwiedzki-D-M", "name": { "family": "Niedzwiedzki", "given": "Dariusz M." }, "orcid": "0000-0002-1976-9296" }, { "id": "Banerjee-P", "name": { "family": "Banerjee", "given": "Parag" }, "orcid": "0000-0003-0401-8155" } ] }, "title": "Amorphous Cu_(2-\u03b4)O as Passivation Layer for Ultra Long Stability of Copper Oxide Nanowires in Photoelectrochemical Environments", "ispublished": "pub", "full_text_status": "restricted", "keywords": "amorphous copper oxide, CuO nanowires, photocathodes", "note": "\u00a9 2018 The Electrochemical Society. \n\nJES Focus Issue on Advances in Electrochemical Processes for Interconnect Fabrication in Integrated Circuits. \n\nManuscript submitted February 26, 2018; revised manuscript received April 20, 2018. Published May 22, 2018. \n\nPartial support is acknowledged from the US\u2212India Partnership to Advance Clean Energy-Research (PACE-R) for the Solar Energy Research Institute for India and the United States (SERIIUS), funded jointly by the U.S. Department of Energy (Office of Science, Office of Basic Energy Sciences, and Energy Efficiency and Renewable Energy, Solar Energy Technology Program, under Subcontract DEAC36-08GO28308 to the National Renewable Energy Laboratory, Golden, CO) and the Government of India, through the Department of Science and Technology under Subcontract IUSSTF/JCERDC-SERIIUS/2012 dated 22nd Nov 2012. The XPS measurements were made possible through the support from NSF CBET MRI grant # 1337374. Microscopy facilities in the Institute of Materials Science and Engineering (I-MSE), Washington University is acknowledged. Support from Professor Pratim Biswas' group at Washington University is acknowledged for use of the photoelectrochemical characterization facility. The Photosynthetic Antenna Research Center at Washington University is acknowledged for performing the transient absorption spectroscopy measurements.", "abstract": "Core-shell CuO-Cu_2O nanowires with a surface amorphous Cu2-\u03b4O layer leads to high stability photocathodes for use in photoelectrochemical splitting of water. The nanowires are synthesized via carbothermal reduction of CuO nanowires at 300\u00b0C during which a 2\u20133 nm conformal and amorphous Cu_(2-\u03b4)O layer is formed on the nanowire surface. This Cu_(2-\u03b4)O layer enhances photocurrent and improves photocorrosion stability of the nanowires. While catalyst-free, pristine CuO nanowires show a photocurrent density is 0.50 mA/cm^2 and a stability of 53% after 3.4 hours of testing at \u22120.50 V under AM1.5 G conditions; the catalyst-free, carbothermally reduced nanowires achieve a photocurrent density of 0.75 mA/cm^2 and an improved stability of 96% under identical test conditions. The mechanism of enhanced photocurrent and its stability is discussed in the context of extensive pre and post test nanowire characterization.", "date": "2018-05-22", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "165", "number": "7", "publisher": "Electrochemical Society", "pagerange": "H417-H424", "id_number": "CaltechAUTHORS:20180822-111107327", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180822-111107327", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "US\u2212India Partnership to Advance Clean Energy-Research" }, { "agency": "Department of Energy (DOE)", "grant_number": "DEAC36-08GO28308" }, { "agency": "Department of Science and Technology (India)", "grant_number": "IUSSTF/JCERDC-SERIIUS/2012" }, { "agency": "NSF", "grant_number": "CBET-1337374" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.1131807jes", "pub_year": "2018", "author_list": "Banerjee, Sriya; Wu, Fei; et el." }, { "id": "https://authors.library.caltech.edu/records/v21cm-9mk69", "eprint_id": 85429, "eprint_status": "archive", "datestamp": "2023-08-19 09:10:46", "lastmod": "2023-10-18 18:13:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kafaie-Shirmanesh-G", "name": { "family": "Kafaie Shirmanesh", "given": "Ghazaleh" }, "orcid": "0000-0003-1666-3215" }, { "id": "Sokhoyan-R", "name": { "family": "Sokhoyan", "given": "Ruzan" }, "orcid": "0000-0003-4599-6350" }, { "id": "Pala-R-A", "name": { "family": "Pala", "given": "Ragip A." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Dual-Gated Active Metasurface at 1550 nm with Wide (>300\u00b0) Phase Tunability", "ispublished": "pub", "full_text_status": "public", "keywords": "Tunable metasurface, transparent conducting oxide, beam steering, active nanophotonics, epsilon-near-zero materials,\nfield effect modulation", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: January 25, 2018; Revised: March 6, 2018; Published: March 23, 2018. \n\nThis work was supported by Samsung Electronics (G.K.S., R.S., and H.A.A.) and the Air Force Office of Scientific Research under Grant FA9550-16-1-0019 (R.A.P.). The authors used facilities supported by the Kavli Nanoscience Institute (KNI) and Joint Center for Artificial Photosynthesis (JCAP) at Caltech. The authors would like to thank Carol Garland for help with the TEM imaging. The authors gratefully acknowledge useful discussions with Dr. Yao-Wei Huang, Dr. Pin Chieh Wu, and Dr. Duhyun Lee. The authors also gratefully acknowledge Erin Burkett and Christina Burch from the Hixon Writing Center at Caltech for providing feedback and guidance on writing the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nl8b00351_si_001.pdf
", "abstract": "Active metasurfaces composed of electrically reconfigurable nanoscale subwavelength antenna arrays can enable real-time control of scattered light amplitude and phase. Achievement of widely tunable phase and amplitude in chip-based active metasurfaces operating at or near 1550 nm wavelength has considerable potential for active beam steering, dynamic hologram rendition, and realization of flat optics with reconfigurable focal lengths. Previously, electrically tunable conducting oxide-based reflectarray metasurfaces have demonstrated dynamic phase control of reflected light with a maximum phase shift of 184\u00b0 ( Nano Lett. 2016, 16, 5319). Here, we introduce a dual-gated reflectarray metasurface architecture that enables much wider (>300\u00b0) phase tunability. We explore light-matter interactions with dual-gated metasurface elements that incorporate two independent voltage-controlled MOS field effect channels connected in series to form a single metasurface element that enables wider phase tunability. Using indium tin oxide (ITO) as the active metasurface material and a composite hafnia/alumina gate dielectric, we demonstrate a prototype dual-gated metasurface with a continuous phase shift from 0 to 303\u00b0 and a relative reflectance modulation of 89% under applied voltage bias of 6.5 V.", "date": "2018-05-09", "date_type": "published", "publication": "Nano Letters", "volume": "18", "number": "5", "publisher": "American Chemical Society", "pagerange": "2957-2963", "id_number": "CaltechAUTHORS:20180323-134241739", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180323-134241739", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Samsung Electronics" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0019" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acs.nanolett.8b00351", "primary_object": { "basename": "nl8b00351_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v21cm-9mk69/files/nl8b00351_si_001.pdf" }, "pub_year": "2018", "author_list": "Kafaie Shirmanesh, Ghazaleh; Sokhoyan, Ruzan; et el." }, { "id": "https://authors.library.caltech.edu/records/21g9f-08g90", "eprint_id": 85969, "eprint_status": "archive", "datestamp": "2023-08-19 09:09:12", "lastmod": "2023-10-18 19:08:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Umehara-Mitsutaro", "name": { "family": "Umehara", "given": "Mitsutaro" }, "orcid": "0000-0001-8665-0028" }, { "id": "Stein-H-S", "name": { "family": "Stein", "given": "Helge S." }, "orcid": "0000-0002-3461-0232" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Alkaline-stable nickel manganese oxides with ideal band gap for solar fuel photoanodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nReceived 16th October 2017, Accepted 9th April 2018, First published on 10th April 2018. \n\nThis work is performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC000499. The authors thanks Paul F. Newhouse for assistance in optical spectra measurement. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c7cc08002f1_si.pdf
", "abstract": "Combinatorial (photo)electrochemical studies of the (Ni\u2013Mn)O_x system reveal a range of promising materials for oxygen evolution photoanodes. X-ray diffraction, quantum efficiency, and optical spectroscopy mapping reveal stable photoactivity of NiMnO_3 in alkaline conditions with photocurrent onset commensurate with its 1.9 eV direct band gap. The photoactivity increases upon mixture with 10\u201360% Ni_6MnO_8 providing an example of enhanced charge separation via heterojunction formation in mixed-phase thin film photoelectrodes. Density functional theory-based hybrid functional calculations of the band edge energies in this oxide reveal that a somewhat smaller than typical fraction of exact exchange is required to explain the favorable valence band alignment for water oxidation.", "date": "2018-05-04", "date_type": "published", "publication": "Chemical Communications", "volume": "54", "number": "36", "publisher": "Royal Society of Chemistry", "pagerange": "4625-4628", "id_number": "CaltechAUTHORS:20180419-092221814", "issn": "1359-7345", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180419-092221814", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC000499" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c7cc08002f", "primary_object": { "basename": "c7cc08002f1_si.pdf", "url": "https://authors.library.caltech.edu/records/21g9f-08g90/files/c7cc08002f1_si.pdf" }, "pub_year": "2018", "author_list": "Suram, Santosh K.; Zhou, Lan; et el." }, { "id": "https://authors.library.caltech.edu/records/dtcd9-sfj08", "eprint_id": 85483, "eprint_status": "archive", "datestamp": "2023-08-19 09:05:48", "lastmod": "2023-10-18 18:15:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Ritzert-N-L", "name": { "family": "Ritzert", "given": "Nicole L." } }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Tan-Haiyan", "name": { "family": "Tan", "given": "Haiyan" } }, { "id": "Hale-W-G", "name": { "family": "Hale", "given": "William G." } }, { "id": "Jiang-Jingjing", "name": { "family": "Jiang", "given": "Jingjing" } }, { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan" }, "orcid": "0000-0001-6461-9214" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Moffat-T-P", "name": { "family": "Moffat", "given": "Thomas P." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Performance and failure modes of Si anodes patterned with thin-film Ni catalyst islands for water oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2018. \n\nThe article was received on 05 Dec 2017, accepted on 03 Mar 2018 and first published on 06 Mar 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. UV-vis spectroscopy was performed at the Molecular Materials Research Center (MMRC) in the Beckman Institute at the California Institute of Technology. This work was also supported by the Gordon and Betty Moore Foundation under award no. GBMF1225. We thank A. Carim, M. Shaner, F. Saadi, J. Velazquez, and C. Xiang from Caltech for stimulating discussions. We also thank K. Walczak (Lawrence Berkeley National Laboratory) for preparation of the ion-implanted Si n^+np^+ substrates. The NIST work was supported by the American Recovery and Reinvestment funds. N. L. R. acknowledges the National Institute of Standards and Technology-National Research Council research associateship program for a postdoctoral fellowship. \n\nAuthor contributions: K. S. and N. S. L designed research; K. S., N. R., J. J., H. T., W. G. H., J. J., I. A. M., and T. P. M. performed experiments; K. S., N. R., J. J., H. T., K. M. P., T. P. M., B. S. B., and N. S. L. analyzed data; and K. S., N. R., K. M. P., T. P. M., B. S. B., and N. S. L. wrote the paper. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c7se00583k1.pdf
", "abstract": "Silicon photoanodes patterned with thin-film Ni catalyst islands exhibited stable oxygen evolution for over 240 h of continuous operation in 1.0 mol L^(\u22121) KOH under simulated sunlight conditions. Buried-junction np^+-Si(111) photoanodes with an 18.0% filling fraction of a square array of Ni microelectrodes, np^+-Si(111)|Ni\u03bcE_(18.0%), demonstrated performance equivalent to a Ni anode in series with a photovoltaic device having an open-circuit voltage of 538 \u00b1 20 mV, a short-circuit current density of 20.4 \u00b1 1.3 mA cm^(\u22122), and a photovoltaic efficiency of 6.7 \u00b1 0.9%. For the np^+-Si(111)|Ni\u03bcE_(18.0%) samples, the photocurrent density at the equilibrium potential for oxygen evolution was 12.7 \u00b1 0.9 mA cm^(\u22122), yielding an ideal regenerative cell solar-to-oxygen conversion efficiency of 0.47 \u00b1 0.07%. The photocurrent passed exclusively through the Ni catalyst islands to evolve O_2 with nearly 100% faradaic efficiency, while a passivating, insulating surface layer of SiO_x formed in situ on areas of the Si in direct contact with the electrolyte. The (photo)electrochemical behavior of Si electrodes patterned with varying areal filling fractions of Ni catalyst islands was also investigated. The stability and efficiency of the patterned-catalyst Si electrodes were affected by the filling fraction of the Ni catalyst, the orientation and dopant type of the substrates, and the measurement conditions. The electrochemical behavior at different stages of operation, including Ni catalyst activation, Si passivation, stable operation, and device failure, was affected by the dynamic processes of anodic formation and isotropic dissolution of SiO_x on the exposed Si. Ex situ and operando microscopic and spectroscopic studies revealed that these processes were three-dimensional and spatially non-uniform across the surface of the substrate, and occurred near the active catalyst islands. The patterned catalyst/substrate electrodes serve as a model system for accelerated studies of failure mechanisms in photoanodes protected by multifunctional catalytic coatings or other hole-conductive thin-film coatings that contain defects.", "date": "2018-05-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "2", "number": "5", "publisher": "Royal Society of Chemistry", "pagerange": "983-998", "id_number": "CaltechAUTHORS:20180328-133308643", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180328-133308643", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "American Recovery and Reinvestment Act (ARRA)" }, { "agency": "National Institute of Standards and Technology (NIST)" }, { "agency": "National Research Council" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C7SE00583K", "primary_object": { "basename": "c7se00583k1.pdf", "url": "https://authors.library.caltech.edu/records/dtcd9-sfj08/files/c7se00583k1.pdf" }, "pub_year": "2018", "author_list": "Sun, Ke; Ritzert, Nicole L.; et el." }, { "id": "https://authors.library.caltech.edu/records/rk3kf-n2c36", "eprint_id": 85386, "eprint_status": "archive", "datestamp": "2023-08-19 08:51:11", "lastmod": "2023-10-18 18:10:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Zhiqiang", "name": { "family": "Cheng", "given": "Zhiqiang" }, "orcid": "0000-0003-2824-9126" }, { "id": "Zhao-Shengzhe", "name": { "family": "Zhao", "given": "Shengzhe" }, "orcid": "0000-0001-9118-2417" }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" } ] }, "title": "A novel preparation method for ZnO/\u03b3-Al_2O_3 nanofibers with enhanced absorbability and improved photocatalytic water-treatment performance by Ag nanoparticles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 The Royal Society of Chemistry. \n\nThe article was received on 28 Dec 2017, accepted on 24 Feb 2018 and first published on 27 Feb 2018. \n\nThis work was funded by the Jilin Province provincial industrial innovation special funds project (2018C041-2), the Jilin Provincial Department of Science and Technology Natural Science Foundation (20180101212JC) and the Changchun Science and Technology Project (17DY012). The authors would like to thank Dr Ian Sullivan (California Institute of Technology, USA) for polishing the manuscript. \n\nThe authors declared that they have no conflicts of interest to this work.\n\nSupplemental Material - c7nr09683f1_si.pdf
", "abstract": "A novel method for synthesizing ZnO/\u03b3-Al_2O_3 nanofibers by electrospinning and subsequent calcination is reported. The prepared nanofibers were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The ZnO/\u03b3-Al_2O_3 nanofibers exhibited excellent capacity for adsorbing organics with a negative zeta potential such as methyl orange (95.8%) and heavy metal ions such as Cr(VI) in aqueous solution. The mechanism of adsorption was investigated, and the adsorption results were fitted using the Langmuir and Freundlich models. Once silver nanoparticles (Ag NPs) were decorated on the surface of the nanofibers by photoreduction, the Ag/ZnO/\u03b3-Al_2O_3 nanofibers manifested efficient photocatalytic degradation of methyl orange under UV-light illumination. Results confirmed that our Ag/ZnO/\u03b3-Al_2O_3 nanofibers are a promising adsorbent for the removal of methyl orange and Cr(VI) ions and the adsorbent can be sustainably reused.", "date": "2018-04-21", "date_type": "published", "publication": "Nanoscale", "volume": "10", "number": "15", "publisher": "Royal Society of Chemistry", "pagerange": "6892-6899", "id_number": "CaltechAUTHORS:20180321-074041990", "issn": "2040-3364", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180321-074041990", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Jilin Province Provincial Industrial Innovation Special Funds Project", "grant_number": "2018C041-2" }, { "agency": "Jilin Provincial Department of Science and Technology Natural Science Foundation", "grant_number": "20180101212JC" }, { "agency": "Changchun Science and Technology Project", "grant_number": "17DY012" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C7NR09683F", "primary_object": { "basename": "c7nr09683f1_si.pdf", "url": "https://authors.library.caltech.edu/records/rk3kf-n2c36/files/c7nr09683f1_si.pdf" }, "pub_year": "2018", "author_list": "Cheng, Zhiqiang; Zhao, Shengzhe; et el." }, { "id": "https://authors.library.caltech.edu/records/72y3s-kga67", "eprint_id": 85303, "eprint_status": "archive", "datestamp": "2023-08-19 08:47:35", "lastmod": "2023-10-18 18:04:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Zhou-Wuzong", "name": { "family": "Zhou", "given": "Wuzong" }, "orcid": "0000-0001-9752-7076" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "High Rate Electrochemical Reduction of Carbon Monoxide to Ethylene using Cu-Nanoparticle-Based Gas Diffusion Electrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: January 31, 2018; Accepted: March 13, 2018; Published: March 13, 2018. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The authors also acknowledge experimental assistance from Xinghao Zhou, Dr. Hsiang-Yun Chen, Dr. Yungchieh Lai, and Dr. Bruce S. Brunschwig. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz8b00164_si_001.pdf
", "abstract": "Gas diffusion electrodes (GDEs) with high electrochemically active surface areas (ECSAs) and triple-phase boundaries for efficient gas, electron, and ion transport offer a unique opportunity for high-rate electrochemical CO reduction (COR) in relative to traditional aqueous configurations. Cu-nanoparticle-based GDEs were fabricated by applying a mixture of carbon powders, copper acetate aqueous solution, and Teflon onto a Cu gauze substrate. The catalyst-coated substrate was air-dried, mechanically pressed, and subsequently annealed under forming gas to produce GDEs. Two distinctive types of GDE configurations, a flow-through configuration and a flow-by configuration, were constructed, characterized, and tested to quantitatively evaluate the effects of reactant gas transport on the activity and the selectivity of the GDE materials for COR. In the flow-through configuration, a high partial current density of 50.8 mA cm^(\u20132) for COR to C_2H_4 was achieved at \u22120.85 V vs RHE in 10 M KOH at \u221215 \u00b0C, while in the flow-by configuration with the same catalyst materials the partial current density for C_2H_4 generation was limited to <1 mA cm^(\u20132).", "date": "2018-04-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "4", "publisher": "American Chemical Society", "pagerange": "855-860", "id_number": "CaltechAUTHORS:20180314-101126488", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180314-101126488", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b00164", "primary_object": { "basename": "nz8b00164_si_001.pdf", "url": "https://authors.library.caltech.edu/records/72y3s-kga67/files/nz8b00164_si_001.pdf" }, "pub_year": "2018", "author_list": "Han, Lihao; Zhou, Wuzong; et el." }, { "id": "https://authors.library.caltech.edu/records/xdkxp-63937", "eprint_id": 85354, "eprint_status": "archive", "datestamp": "2023-08-19 08:46:17", "lastmod": "2023-10-18 18:08:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "DuChene-Joseph-S", "name": { "family": "DuChene", "given": "Joseph S." }, "orcid": "0000-0002-7145-323X" }, { "id": "Tagliabue-Giulia", "name": { "family": "Tagliabue", "given": "Giulia" }, "orcid": "0000-0003-4587-728X" }, { "id": "Welch-Alex-J", "name": { "family": "Welch", "given": "Alex J." }, "orcid": "0000-0003-2132-9617" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Hot Hole Collection and Photoelectrochemical CO_2 Reduction with Plasmonic Au/p-GaN Photocathodes", "ispublished": "pub", "full_text_status": "public", "keywords": "Photoelectrochemistry, hot carriers, plasmonic photocathode, CO2 reduction, Schottky barrier, hot holes", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: January 18, 2018; Revised: February 28, 2018; Publication Date (Web): March 9, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. G.T. acknowledges support from the Swiss National Science Foundation through the Early Postdoc Mobility Fellowship, Grant P2EZP2_159101 and the Advanced Mobility Fellowship, Grant P300P2_171417. We thank Dr. Ravishankar Sundararaman, Dr. Prineha Narang, and Adam Jermyn for fruitful discussions of hot-carrier energy distributions. We thank Dr. Matthias Richter for XPS characterization of p-type NiO films. \n\nAuthor Contributions: J.S.D., G.T., and H.A.A. conceived the idea, designed the experiments, and wrote the manuscript. J.S.D. and G.T. performed all photoelectrochemical experiments. J.S.D., G.T., and A.J.W. fabricated devices. W.-H.C. performed optical characterization and assisted with gas chromatography experiments. H.A.A. supervised the project. All authors have given approval to the final version of the manuscript. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nl8b00241_si_001.pdf
", "abstract": "Harvesting nonequilibrium hot carriers from plasmonic-metal nanostructures offers unique opportunities for driving photochemical reactions at the nanoscale. Despite numerous examples of hot electron-driven processes, the realization of plasmonic systems capable of harvesting hot holes from metal nanostructures has eluded the nascent field of plasmonic photocatalysis. Here, we fabricate gold/p-type gallium nitride (Au/p-GaN) Schottky junctions tailored for photoelectrochemical studies of plasmon-induced hot-hole capture and conversion. Despite the presence of an interfacial Schottky barrier to hot-hole injection of more than 1 eV across the Au/p-GaN heterojunction, plasmonic Au/p-GaN photocathodes exhibit photoelectrochemical properties consistent with the injection of hot holes from Au nanoparticles into p-GaN upon plasmon excitation. The photocurrent action spectrum of the plasmonic photocathodes faithfully follows the surface plasmon resonance absorption spectrum of the Au nanoparticles and open-circuit voltage studies demonstrate a sustained photovoltage during plasmon excitation. Comparison with Ohmic Au/p-NiO heterojunctions confirms that the vast majority of hot holes generated via interband transitions in Au are sufficiently hot to inject above the 1.1 eV interfacial Schottky barrier at the Au/p-GaN heterojunction. We further investigated plasmon-driven photoelectrochemical CO_2 reduction with the Au/p-GaN photocathodes and observed improved selectivity for CO production over H_2 evolution in aqueous electrolytes. Taken together, our results offer experimental validation of photoexcited hot holes more than 1 eV below the Au Fermi level and demonstrate a photoelectrochemical platform for harvesting hot carriers to drive solar-to-fuel energy conversion.", "date": "2018-04-11", "date_type": "published", "publication": "Nano Letters", "volume": "18", "number": "4", "publisher": "American Chemical Society", "pagerange": "2545-2550", "id_number": "CaltechAUTHORS:20180319-104159108", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180319-104159108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P2EZP2_159101" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "P300P2_171417" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.8b00241", "primary_object": { "basename": "nl8b00241_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xdkxp-63937/files/nl8b00241_si_001.pdf" }, "pub_year": "2018", "author_list": "DuChene, Joseph S.; Tagliabue, Giulia; et el." }, { "id": "https://authors.library.caltech.edu/records/y767f-w2r98", "eprint_id": 85331, "eprint_status": "archive", "datestamp": "2023-08-19 08:27:01", "lastmod": "2023-10-18 18:06:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chapovetsky-Alon", "name": { "family": "Chapovetsky", "given": "Alon" }, "orcid": "0000-0001-8095-8830" }, { "id": "Welborn-Matthew-G", "name": { "family": "Welborn", "given": "Matthew" }, "orcid": "0000-0001-8659-6535" }, { "id": "Luna-M", "name": { "family": "Luna", "given": "M." } }, { "id": "Haiges-Ralf", "name": { "family": "Haiges", "given": "Ralf" }, "orcid": "0000-0003-4151-3593" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" }, { "id": "Marinescu-Smaranda-C", "name": { "family": "Marinescu", "given": "Smaranda C." }, "orcid": "0000-0003-2106-8971" } ] }, "title": "Pendant Hydrogen-Bond Donors in Cobalt Catalysts Independently Enhance CO\u2082 Reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: December 19, 2017. Published: February 23, 2018. \n\nThis work was supported by the University of Southern California and the National Science Foundation (NSF) through the CAREER award (CHE-1555387) and the Chemistry of Life Processes Program (CHE-1611581). This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We are grateful to the USC Wrigley Institute for a Norma and Jerol Sonosky summer fellowship to A.C. M.W. thanks the Resnick Sustainability Institute for a postdoctoral fellowship. We are grateful to NSF (Grant CRIF 1048807) and USC for their sponsorship of NMR spectrometers and an X-ray diffractometer. \n\nA.C. and M.W.: equal contribution. \n\nCCDC 1590218\u20131590221 contain the supplementary crystallographic data for this manuscript. \n\nThe authors declare no competing financial interest.\n\nPublished - acscentsci.7b00607.pdf
Supplemental Material - oc7b00607_si_001.pdf
Supplemental Material - oc7b00607_si_002.cif
Supplemental Material - oc7b00607_si_003.cif
Supplemental Material - oc7b00607_si_004.cif
Supplemental Material - oc7b00607_si_005.cif
", "abstract": "The bioinspired incorporation of pendant proton donors into transition metal catalysts is a promising strategy for converting environmentally deleterious CO\u2082 to higher energy products. However, the mechanism of proton transfer in these systems is poorly understood. Herein, we present a series of cobalt complexes with varying pendant secondary and tertiary amines in the ligand framework with the aim of disentangling the roles of the first and second coordination spheres in CO\u2082 reduction catalysis. Electrochemical and kinetic studies indicate that the rate of catalysis shows a first-order dependence on acid, CO\u2082, and the number of pendant secondary amines, respectively. Density functional theory studies explain the experimentally observed trends and indicate that pendant secondary amines do not directly transfer protons to CO\u2082, but instead bind acid molecules from solution. Taken together, these results suggest a mechanism in which noncooperative pendant amines facilitate a hydrogen-bonding network that enables direct proton transfer from acid to the activated CO\u2082 substrate.", "date": "2018-03-28", "date_type": "published", "publication": "ACS Central Science", "volume": "4", "number": "3", "publisher": "American Chemical Society", "pagerange": "397-404", "id_number": "CaltechAUTHORS:20180315-111119688", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180315-111119688", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1555387" }, { "agency": "NSF", "grant_number": "CHE-1611581" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-1048807" }, { "agency": "University of Southern California" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscentsci.7b00607", "pmcid": "PMC5879468", "primary_object": { "basename": "oc7b00607_si_004.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_004.cif" }, "related_objects": [ { "basename": "oc7b00607_si_005.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_005.cif" }, { "basename": "acscentsci.7b00607.pdf", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/acscentsci.7b00607.pdf" }, { "basename": "oc7b00607_si_001.pdf", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_001.pdf" }, { "basename": "oc7b00607_si_002.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_002.cif" }, { "basename": "oc7b00607_si_003.cif", "url": "https://authors.library.caltech.edu/records/y767f-w2r98/files/oc7b00607_si_003.cif" } ], "pub_year": "2018", "author_list": "Chapovetsky, Alon; Welborn, Matthew; et el." }, { "id": "https://authors.library.caltech.edu/records/8tsby-3pm97", "eprint_id": 85387, "eprint_status": "archive", "datestamp": "2023-08-19 08:21:21", "lastmod": "2023-10-18 18:10:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lee-Nien-En", "name": { "family": "Lee", "given": "Nien-En" }, "orcid": "0000-0002-3172-7750" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Agapito-Luis-A", "name": { "family": "Agapito", "given": "Luis A." } }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Charge transport in organic molecular semiconductors from first principles: The bandlike hole mobility in a naphthalene crystal", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Physical Society. \n\nReceived 1 December 2017; revised manuscript received 9 February 2018; published 16 March 2018. \n\nThe authors thank M. Palummo for discussions. N.-E.L. acknowledges the Physics department at Caltech for the TA Relief Fellowship. M.B. and L.A. acknowledge support by the National Science Foundation under Grant No. ACI-1642443, which provided for basic theory and electron-phonon code development. This work was partially supported by the Young Investigator Program of the Air Force Office of Scientific Research (AFOSR), under Grant FA9550-18-1-0280. J.-J. Zhou was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The development of the scattering rate and mobility calculations was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevB.97.115203.pdf
Accepted Version - 1712.00490.pdf
", "abstract": "Predicting charge transport in organic molecular crystals is notoriously challenging. Carrier mobility calculations in organic semiconductors are dominated by quantum chemistry methods based on charge hopping, which are laborious and only moderately accurate. We compute from first principles the electron-phonon scattering and the phonon-limited hole mobility of naphthalene crystal in the framework of ab initio band theory. Our calculations combine GW electronic bandstructures, ab initio electron-phonon scattering, and the Boltzmann transport equation. The calculated hole mobility is in very good agreement with experiment between 100 \u2013 300 K, and we can predict its temperature dependence with high accuracy. We show that scattering between intermolecular phonons and holes regulates the mobility, though intramolecular phonons possess the strongest coupling with holes. We revisit the common belief that only rigid molecular motions affect carrier dynamics in organic molecular crystals. Our paper provides a quantitative and rigorous framework to compute charge transport in organic crystals and is a first step toward reconciling band theory and carrier hopping computational methods.", "date": "2018-03-15", "date_type": "published", "publication": "Physical Review B", "volume": "97", "number": "11", "publisher": "American Physical Society", "pagerange": "Art. No. 115203", "id_number": "CaltechAUTHORS:20180321-075518336", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180321-075518336", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-18-1-0280" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevB.97.115203", "primary_object": { "basename": "PhysRevB.97.115203.pdf", "url": "https://authors.library.caltech.edu/records/8tsby-3pm97/files/PhysRevB.97.115203.pdf" }, "related_objects": [ { "basename": "1712.00490.pdf", "url": "https://authors.library.caltech.edu/records/8tsby-3pm97/files/1712.00490.pdf" } ], "pub_year": "2018", "author_list": "Lee, Nien-En; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/33v7a-p2m55", "eprint_id": 84894, "eprint_status": "archive", "datestamp": "2023-08-19 08:17:24", "lastmod": "2023-10-18 16:56:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kempler-Paul-A", "name": { "family": "Kempler", "given": "Paul A." }, "orcid": "0000-0003-3909-1790" }, { "id": "Gonzalez-Miguel-A", "name": { "family": "Gonzalez", "given": "Miguel A." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Hydrogen Evolution with Minimal Parasitic Light Absorption by Dense Co\u2013P Catalyst Films on Structured p-Si Photocathodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: January 9, 2018; Accepted: February 8, 2018; Published: February 8, 2018. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz8b00034_si_001.pdf
", "abstract": "Planar and three-dimensionally structured p-Si devices, consisting of an electrodeposited Co\u2013P catalyst on arrays of Si microwires or Si micropyramids, were used as photocathodes for solar-driven hydrogen evolution in 0.50 M H_2SO_4(aq) to assess the effects of electrode structuring on parasitic absorption by the catalyst. Without the use of an emitter layer, p-Si/Co\u2013P microwire arrays produced a photocurrent density of \u221210 mA cm^(\u20132) at potentials that were 130 mV more positive than those of optimized planar p-Si/Co\u2013P devices. Champion p-Si/Co\u2013P microwire array devices exhibited ideal regenerative cell solar-to-hydrogen efficiencies of >2.5% and were primarily limited by the photovoltage of the p-Si/Co\u2013P junction. The vertical sidewalls of the Si microwire photoelectrodes thus minimized effects due to parasitic absorption at high loadings of catalyst for device structures with or without emitters.", "date": "2018-03-09", "date_type": "published", "publication": "ACS Energy Letters", "volume": "3", "number": "3", "publisher": "American Chemical Society", "pagerange": "612-617", "id_number": "CaltechAUTHORS:20180220-133422256", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180220-133422256", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.8b00034", "primary_object": { "basename": "nz8b00034_si_001.pdf", "url": "https://authors.library.caltech.edu/records/33v7a-p2m55/files/nz8b00034_si_001.pdf" }, "pub_year": "2018", "author_list": "Kempler, Paul A.; Gonzalez, Miguel A.; et el." }, { "id": "https://authors.library.caltech.edu/records/qds76-xyx13", "eprint_id": 84666, "eprint_status": "archive", "datestamp": "2023-08-19 08:11:45", "lastmod": "2023-10-20 21:51:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "McFarland-Eric-W", "name": { "family": "McFarland", "given": "Eric W." } } ] }, "title": "Relative costs of transporting electrical and chemical energy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 Royal Society of Chemistry. \n\nReceived 17th July 2017. Accepted 22nd January 2018. First published on 29th January 2018. \n\nSupport for this work was provided by a graduate fellowship for F. H. S. from the Dow Centre for Sustainable Engineering Innovation at the University of Queensland, Australia. Additional support was provided by U.S. Department of Energy under Award Numbers DEFG02-89ER14048 (E. W. M.), and DE-SC0004993 (N. S. L.). \n\nThere are no conflicts to declare.\n\nPublished - c7ee01987d.pdf
Erratum - C8EE90006J.pdf
", "abstract": "Transportation costs of energy resources are important when determining the overall economics of future energy infrastructure. The majority of long distance energy transmission occurs via merchant ships and pipelines carrying oil or natural gas. In contrast, future energy scenarios often envision vastly altered energy transportation scenarios including very high degrees of grid electrification and widespread installation of hydrogen pipelines. The unit cost of energy transportation varies by over two orders of magnitude. In particular, the costs of electricity and hydrogen transmission are substantially higher than the cost of oil and natural gas transportation. If carbon pricing is to be used to incentivize alternative energy systems, these differences in costs will need to be reduced and used when making meaningful technology comparisons.", "date": "2018-03-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "11", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "469-475", "id_number": "CaltechAUTHORS:20180205-084607037", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180205-084607037", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "University of Queensland" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-89ER14048" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c7ee01987d", "primary_object": { "basename": "C8EE90006J.pdf", "url": "https://authors.library.caltech.edu/records/qds76-xyx13/files/C8EE90006J.pdf" }, "related_objects": [ { "basename": "c7ee01987d.pdf", "url": "https://authors.library.caltech.edu/records/qds76-xyx13/files/c7ee01987d.pdf" } ], "pub_year": "2018", "author_list": "Saadi, Fadl H.; Lewis, Nathan S.; et el." }, { "id": "https://authors.library.caltech.edu/records/s8mmt-5cj55", "eprint_id": 84611, "eprint_status": "archive", "datestamp": "2023-08-19 07:55:21", "lastmod": "2023-10-18 16:24:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hashiba-Hiroshi", "name": { "family": "Hashiba", "given": "Hiroshi" } }, { "id": "Weng-Lien-Chun", "name": { "family": "Weng", "given": "Lien-Chun" } }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Sato-Hiroki-K", "name": { "family": "Sato", "given": "Hiroki K." } }, { "id": "Yotsuhashi-Satoshi", "name": { "family": "Yotsuhashi", "given": "Satoshi" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" } ] }, "title": "Effects of Electrolyte Buffer Capacity on Surface Reactant Species and Reaction Rate of CO_2 in Electrochemical CO_2 Reduction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: November 15, 2017; Revised: January 19, 2018;\nPublished: January 30, 2018.\n\nThe material is based on work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The constant flux simulations were supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. The experimental work and the limiting-current simulations and analysis were supported by Panasonic Corporation under a JCAP Industrial Partnership Agreement.\n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp7b11316_si_001.pdf
", "abstract": "In the aqueous electrochemical reduction of CO_2, the choice of electrolyte is responsible for the catalytic activity and selectivity, although there remains a need for more in-depth understanding of electrolyte effects and mechanisms. In this study, using both experimental and simulation approaches, we report how the buffer capacity of the electrolytes affects the kinetics and equilibrium of surface reactant species and resulting reaction rate of CO_2 with varying partial CO_2 pressure. Electrolytes investigated include KCl (non-buffered), KHCO3 (buffered by bicarbonate), and phosphate buffered electrolytes. Assuming 100% methane production, the simulation successfully explains the experimental trends of maximum CO_2 flux in KCl and KHCO_3, and also highlights the difference between KHCO_3 and phosphate in terms of pKa as well as the impact of buffer capacity. To examine the electrolyte impact on selectivity, the model is run with a constant total current density. Using this model, several factors are elucidated including the importance of local pH, which is not in acid/base equilibrium, the impact of buffer identity and kinetics, and the mass-transport boundary-layer thickness. The gained understanding can help optimize CO_2 reduction in aqueous environments.", "date": "2018-02-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "122", "number": "7", "publisher": "American Chemical Society", "pagerange": "3719-3726", "id_number": "CaltechAUTHORS:20180131-150900860", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180131-150900860", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.7b11316", "primary_object": { "basename": "jp7b11316_si_001.pdf", "url": "https://authors.library.caltech.edu/records/s8mmt-5cj55/files/jp7b11316_si_001.pdf" }, "pub_year": "2018", "author_list": "Hashiba, Hiroshi; Weng, Lien-Chun; et el." }, { "id": "https://authors.library.caltech.edu/records/1p16s-8x456", "eprint_id": 83142, "eprint_status": "archive", "datestamp": "2023-08-19 07:54:25", "lastmod": "2023-10-17 22:55:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Papadakis-G-T", "name": { "family": "Papadakis", "given": "Georgia T." }, "orcid": "0000-0001-8107-9221" }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Rivera-N", "name": { "family": "Rivera", "given": "Nicholas" }, "orcid": "0000-0002-8298-1468" }, { "id": "Buljan-H", "name": { "family": "Buljan", "given": "Hrvoje" } }, { "id": "Engheta-N", "name": { "family": "Engheta", "given": "Nader" } }, { "id": "Solja\u010di\u0107-M", "name": { "family": "Solja\u010di\u0107", "given": "Marin" } } ] }, "title": "Ultralight Angstrom-Scale Optimal Optical Reflectors", "ispublished": "pub", "full_text_status": "public", "keywords": "2D heterotructures, perfect electric conductors, surface plasmons, plasmonic waveguides", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: June 13, 2017; Published: October 11, 2017. \n\nG.T.P. acknowledges fruitful discussions with Prof. P. Yeh. We also thank Prof. Harry A. Atwater, Prof. John D. Joannopoulous, Yi Yang, and Tena Dubcek for helpful discussions. We acknowledge financial support from NG Next at the Northrop Grumman Corporation. G.T.P. acknowledges financial support from the American Association of University Women (AAUW). P.N. acknowledges support from the Harvard University Center for the Environment (HUCE) and faculty startup funding from the John A. Paulson School of Engineering and Applied Sciences at Harvard. R.S. acknowledges startup funding from Rensselaer Polytechnic Institute (RPI). N.E. acknowledges partial support from the U.S. Air Force Office of Scientific Research Multidisciplinary University Research Initiative grant number FA9550-17-1-0002. This research was supported (in part) by the U.S. Army Research Office under contract W911NF-13-D-0001. Calculations in this work were performed on the BlueGene/Q supercomputer in the Center for Computational Innovations (CCI) at RPI, as well as in the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. M.S. (reading and analysis of the manuscript) was supported by S3TEC, an Energy Frontier Research Center funded by the U.S. Department of Energy under grant no. DE-SC0001299. H.B. acknowledges support from the QuantiXLie Center of Excellence.\n\nSubmitted - 1707.06717.pdf
", "abstract": "High reflectance in many state-of-the-art optical devices is achieved with noble metals. However, metals are limited by losses and, for certain applications, by their high mass density. Using a combination of ab initio and optical transfer matrix calculations, we evaluate the behavior of graphene-based angstrom-scale metamaterials and find that they could act as nearly perfect reflectors in the mid\u2013long-wave infrared (IR) range. The low density of states for electron\u2013phonon scattering and interband excitations leads to unprecedented optical properties for graphene heterostructures, especially alternating atomic layers of graphene and hexagonal boron nitride, at wavelengths greater than 10 \u03bcm. At these wavelengths, these materials exhibit reflectivities exceeding 99.7% at a fraction of the weight of noble metals, as well as plasmonic mode confinement and quality factors that are greater by an order of magnitude compared to noble metals. These findings hold promise for ultracompact optical components and waveguides for mid-IR applications. Moreover, unlike metals, the photonic properties of these heterostructures could be actively tuned via chemical and/or electrostatic doping, providing exciting possibilities for tunable devices.", "date": "2018-02-21", "date_type": "published", "publication": "ACS Photonics", "volume": "5", "number": "2", "publisher": "American Chemical Society", "pagerange": "384-389", "id_number": "CaltechAUTHORS:20171113-093317933", "issn": "2330-4022", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171113-093317933", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Northrop Grumman Corporation" }, { "agency": "American Association of University Women" }, { "agency": "Harvard University" }, { "agency": "Rensselaer Polytechnic Institute" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0002" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911NF-13-D-0001" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001299" }, { "agency": "QuantiXLie (Croatia)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsphotonics.7b00609", "primary_object": { "basename": "1707.06717.pdf", "url": "https://authors.library.caltech.edu/records/1p16s-8x456/files/1707.06717.pdf" }, "pub_year": "2018", "author_list": "Papadakis, Georgia T.; Narang, Prineha; et el." }, { "id": "https://authors.library.caltech.edu/records/j4fb2-9zh79", "eprint_id": 84422, "eprint_status": "archive", "datestamp": "2023-08-19 07:49:27", "lastmod": "2023-10-18 16:12:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Lu", "name": { "family": "Wang", "given": "Lu" }, "orcid": "0000-0001-5263-3123" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Li-Youyong", "name": { "family": "Li", "given": "Youyong" }, "orcid": "0000-0002-5248-2756" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Pb-activated Amine-assisted Photocatalytic Hydrogen Evolution Reaction on Organic-Inorganic Perovskites", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 American Chemical Society. \n\nReceived: November 13, 2017; Published: January 19, 2018.\n\nThis work was supported by the National Key Research and Development Program of China (Grants 2017YFA0204800 and 2017YFB0701600), the National Natural Science Foundation of China (Grants 21403146, 51761145013, 21673149). This research was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No.DE-SC0004993. This project is also supported by the Fund for Collaborative Innovation Center of Suzhou Nano Science & Technology, the Priority Academic Program Development of Jiangsu Higher Education Institutions.\n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja7b12028_si_001.pdf
", "abstract": "We report here the reaction mechanism for explicit aqueous solvent quantum mechanics (QM) studies determining the energetics and reaction barriers for the photocatalytic hydrogen evolution reaction (HER) on CH_3NH_3PbI_3 surface. We find that both the lead (Pb) atoms and the surface organic molecules play essential roles, leading to a two-step Pb-activated amine-assisted (PbAAA) reaction mechanism involving an intermediate lead hydride state. Both H of H_2 product are extracted from surface organic molecules, while two protons from the solution migrate along water chains via the Grotthuss mechanism to replace the H in organic molecule. We obtain a reaction barrier of 1.08 eV for photochemical generation of H_2 on CH_3NH_3PbI_3 compared to 2.61 eV for the dark reaction. We expect this HER mechanism can also apply to the other organic perovskites, but the energy barriers and reaction rates may depend on the basicity of electrolyte and intrinsic structures of perovskites.", "date": "2018-02-14", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "140", "number": "6", "publisher": "American Chemical Society", "pagerange": "1994-1997", "id_number": "CaltechAUTHORS:20180119-111711514", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180119-111711514", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFA0204800" }, { "agency": "National Key Research and Development Program of China", "grant_number": "2017YFB0701600" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21403146" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51761145013" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21673149" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Suzhou Nano Science and Technology" }, { "agency": "Jiangsu Higher Education Institutions" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.7b12028", "primary_object": { "basename": "ja7b12028_si_001.pdf", "url": "https://authors.library.caltech.edu/records/j4fb2-9zh79/files/ja7b12028_si_001.pdf" }, "pub_year": "2018", "author_list": "Wang, Lu; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/24dz6-kt634", "eprint_id": 84229, "eprint_status": "archive", "datestamp": "2023-08-19 07:29:32", "lastmod": "2023-10-18 16:00:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhang-Haochen", "name": { "family": "Zhang", "given": "Haochen" }, "orcid": "0000-0002-2774-5868" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Lu-Qi", "name": { "family": "Lu", "given": "Qi" }, "orcid": "0000-0002-0380-2629" }, { "id": "Cheng-Mu-Jeng", "name": { "family": "Cheng", "given": "Mu-Jeng" }, "orcid": "0000-0002-8121-0485" } ] }, "title": "The importance of grand-canonical quantum mechanical methods to describe the effect of electrode potential on the stability of intermediates involved in both electrochemical CO_2 reduction and hydrogen evolution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2018 the Owner Societies. \n\nReceived 5th December 2017, Accepted 1st January 2018, First published on 3rd January 2018. \n\nH. C. Z. and Q. L. acknowledge financial support from the National Natural Science Foundation of China (grant number 21606142). M. J. C. acknowledges financial support from the Ministry of Science and Technology of the Republic of China under grant no. MOST 105-2113-M-006-017-MY2. W. A. G. acknowledges financial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We wish to thank the supercomputer centre at the Tsinghua National Laboratory for Information Science and Technology for providing computational resources. \n\nThere are no conflicts to declare.\n\nSupplemental Material - c7cp08153g1_si.pdf
", "abstract": "The rational design of electrocatalysts to convert CO_2 to fuel requires predicting the effect of the electrode potential (U) on the binding and structures of the intermediates involved in CO_2 electrochemical reduction (CO2ER). In this study, we used grand-canonical quantum mechanics (GC-QM) to keep the potential constant during the reactions (rather than keeping the charge constant as in standard QM) to investigate the effect of Uon adsorption free energies (\u0394Gs) of 14 CO_2ER intermediates on Cu(111) as well as the intermediates involved in the competitive hydrogen evolution reaction (HER). In contrast to most previous theoretical studies where \u0394Gs were calculated under constant charge (= 0, neutral), we calculated \u0394Gs under constant potential (U = 0.0, \u22120.5, \u22121.0, and \u22121.5 V_(SHE)). By comparing the \u0394Gs calculated under constant U (= 0.0 V_(SHE)) to those calculated under constant charge, we found differences up to 0.22 eV which would change the rates at 298 K by a factor of about 5300. In particular we found that the adsorption of species with a C O functional group (i.e., *COOH, *CO, and *CHO) strengthened by up to 0.16 eV as U became more negative by 1 V, whereas the adsorption of \u2013O\u2013 species (i.e., *OH, *OCH3, *COH, and *CHOH) weakened by up to 0.20 eV. For the (111) index surfaces of Cu, Au, Ag, Ir, Ni, Pd, Pt and Rh, we investigated the effect of U on the reaction free energy (\u0394G) at pH = 0 for the crucial elementary steps for CO_2ER (*CO + (H+/e\u2212) \u2192 *CHO, \u0394G = (\u0394G_(*CHO) \u2013 \u0394G_(*CO)) + eU) and HER (* + (H+/e\u2212) \u2192 *H, \u0394G = \u0394G_(*H) + eU. Our results indicated that the influence of U on (\u0394G_(*CHO) \u2013 \u0394G_(*CO)) was metal dependent. In contrast, the energy for converting a proton in solution to H* on the surface, \u0394G_(*H), was barely affected by U(for the studied metals). Overall we found substantial differences (MAD > 0.18 eV) between the \u0394Gs calculated under U = \u22121.0 V_(SHE) (relevant to experiments) and those calculated under constant charge (= 0, neutral) common to most theoretical investigations. Therefore, we strongly recommend application GC-QM to obtain accurate energetics for CO_2ER.", "date": "2018-01-28", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "20", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "2549-2557", "id_number": "CaltechAUTHORS:20180110-102226313", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180110-102226313", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "21606142" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 105-2113-M-006-017-MY2" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c7cp08153g", "primary_object": { "basename": "c7cp08153g1_si.pdf", "url": "https://authors.library.caltech.edu/records/24dz6-kt634/files/c7cp08153g1_si.pdf" }, "pub_year": "2018", "author_list": "Zhang, Haochen; Goddard, William A., III; et el." }, { "id": "https://authors.library.caltech.edu/records/4btbw-2h207", "eprint_id": 83651, "eprint_status": "archive", "datestamp": "2023-08-19 07:19:24", "lastmod": "2023-10-17 23:19:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Fackler-S-W", "name": { "family": "Fackler", "given": "Sean W." } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "N'Diaye-A-T", "name": { "family": "N'Diaye", "given": "Alpha T." } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter S." }, "orcid": "0000-0002-8693-4562" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combinatorial Discovery of Lanthanum-Tantalum Oxynitride Solar Light Absorbers with Dilute Nitrogen for Solar Fuels Applications", "ispublished": "pub", "full_text_status": "public", "keywords": "oxynitride, light absorber, solar fuel, x-ray absorption spectroscopy, combinatorial materials science", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: September 29, 2017; Revised: November 20, 2017;\nPublished: November 27, 2017. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Dr. Chi Ma and Prof. George R. Rossman for assistance with WDS measurements. This research used resources of the Advanced Light Source, which is a DOE Office of Science User Facility under contract no. DE-AC02-05CH11231. The authors also thank Yi-Sheng Liu, Li Cheng Kao, and Yifan Ye for assistance with XANES measurements at ALS beamline 6.3.1.2. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - co7b00143_si_001.pdf
", "abstract": "Oxynitrides with the photoelectrochemical stability of oxides and desirable band energetics of nitrides comprise a promising class of materials for solar photochemistry. Challenges in synthesizing a wide variety of oxynitride materials has limited exploration of this class of functional materials, which we address using a reactive cosputtering combined with rapid thermal processing method to synthesize multi-cation\u2013multi-anion libraries. We demonstrate the synthesis of a La_xTa_(1\u2013x)O_yN_z thin film composition spread library and its characterization by both traditional thin film materials characterization and custom combinatorial optical spectroscopy and X-ray absorption near edge spectroscopy (XANES) techniques, ultimately establishing structure-chemistry-property relationships. We observe that over a substantial La\u2013Ta composition range the thin films crystallize in the same perovskite LaTaON2 structure with significant variation of anion chemistry. The relative invariance in optical band gap demonstrates a remarkable decoupling of composition and band energetics so that the composition can be optimized while retaining the desirable 2 eV band gap energy. We also demonstrate the intercalation of diatomic nitrogen into the La_3TaO_7 structure, which gives rise to a direct-allowed optical transition at 2.2 eV, less than half the value of the oxide's band gap. These findings motivate further exploration of the visible light response of this material that is predicted to be stable over a wide range of electrochemical potential.", "date": "2018-01-08", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "20", "number": "1", "publisher": "American Chemical Society", "pagerange": "26-34", "id_number": "CaltechAUTHORS:20171204-074721984", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171204-074721984", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.7b00143", "primary_object": { "basename": "co7b00143_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4btbw-2h207/files/co7b00143_si_001.pdf" }, "pub_year": "2018", "author_list": "Suram, Santosh K.; Fackler, Sean W.; et el." }, { "id": "https://authors.library.caltech.edu/records/nj5vt-2ay38", "eprint_id": 83453, "eprint_status": "archive", "datestamp": "2023-08-21 22:34:12", "lastmod": "2023-10-17 23:08:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Soniat-M", "name": { "family": "Soniat", "given": "Marielle" } }, { "id": "Tesfaye-M", "name": { "family": "Tesfaye", "given": "Meron" } }, { "id": "Brooks-D-J", "name": { "family": "Brooks", "given": "Daniel" } }, { "id": "Merinov-B-V", "name": { "family": "Merinov", "given": "Boris" }, "orcid": "0000-0002-2783-4262" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" }, { "id": "Houle-F-A", "name": { "family": "Houle", "given": "Frances A." }, "orcid": "0000-0001-5571-2548" } ] }, "title": "Predictive simulation of non-steady-state transport of gases through rubbery polymer membranes", "ispublished": "pub", "full_text_status": "public", "keywords": "Rubbery polymers; Reaction-diffusion modeling; Gas transport", "note": "\u00a9 2017 Published by Elsevier Ltd. \n\nReceived 22 August 2017, Revised 14 October 2017, Accepted 22 November 2017, Available online 24 November 2017.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The reaction-diffusion simulations were performed by M. S. and F. H., and experimental measurements were performed by M. T. and A. W., supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. M. T. thanks the National Science Foundation Graduate Research Fellowship under Grant No. DGE 1106400. D. B., B. M. and W. A. G. acknowledge funding from Bosch Energy Research Network Grant No 07.23.CS.15 for the MD simulation work. Bosch Energy Research had no involvement in decisions concerning data collection, data processing, writing, or article submission. The authors are grateful to Dr. Daniel J. Miller (JCAP, LBNL) for many helpful discussions on membrane polymer science, to Mr. Ezra L. Clark (JCAP, LBNL) for data on photoelectrochemical production of methane, and to Dr. William D. Hinsberg (Columbia Hill Technical Consulting) for discussions on the use of Kinetiscope in this work.\n\nAccepted Version - 1242-Houle-PDMS_JCAP-last_Author_version.pdf
Supplemental Material - 1-s2.0-S0032386117311254-mmc1.docx
", "abstract": "A multiscale, physically-based, reaction-diffusion kinetics model is developed for non-steady-state transport of simple gases through a rubbery polymer. Experimental data from the literature, new measurements of non-steady-state permeation and a molecular dynamics simulation of a gas-polymer sticking probability for a typical system are used to construct and validate the model framework. Using no adjustable parameters, the model successfully reproduces time-dependent experimental data for two distinct systems: (1) O_2 quenching of a phosphorescent dye embedded in poly(n-butyl(amino) thionylphosphazene), and (2) O_2, N_2, CH_4 and CO_2 transport through poly(dimethyl siloxane). The calculations show that in the pre-steady-state regime, permeation is only correctly described if the sorbed gas concentration in the polymer is dynamically determined by the rise in pressure. The framework is used to predict selectivity targets for two applications involving rubbery membranes: CO_2 capture from air and blocking of methane cross-over in an aged solar fuels device.", "date": "2018-01-03", "date_type": "published", "publication": "Polymer", "volume": "134", "publisher": "Elsevier", "pagerange": "125-142", "id_number": "CaltechAUTHORS:20171127-141541426", "issn": "0032-3861", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171127-141541426", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE 1106400" }, { "agency": "Bosch Energy Research Network", "grant_number": "07.23.CS.15" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.polymer.2017.11.055", "primary_object": { "basename": "1-s2.0-S0032386117311254-mmc1.docx", "url": "https://authors.library.caltech.edu/records/nj5vt-2ay38/files/1-s2.0-S0032386117311254-mmc1.docx" }, "related_objects": [ { "basename": "1242-Houle-PDMS_JCAP-last_Author_version.pdf", "url": "https://authors.library.caltech.edu/records/nj5vt-2ay38/files/1242-Houle-PDMS_JCAP-last_Author_version.pdf" } ], "pub_year": "2018", "author_list": "Soniat, Marielle; Tesfaye, Meron; et el." }, { "id": "https://authors.library.caltech.edu/records/vz524-3yb66", "eprint_id": 83218, "eprint_status": "archive", "datestamp": "2023-08-19 06:49:57", "lastmod": "2023-10-17 22:59:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Reyes-Lillo-S-E", "name": { "family": "Reyes-Lillo", "given": "Sebastian E." }, "orcid": "0000-0003-0012-9958" }, { "id": "Li-Guo", "name": { "family": "Li", "given": "Guo" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Qu-Xiaohui", "name": { "family": "Qu", "given": "Xiaohui" } }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin" }, "orcid": "0000-0003-2495-5509" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Discovery and Characterization of a Pourbaix-Stable, 1.8 eV Direct Gap Bismuth Manganate Photoanode", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: August 25, 2017; Revised: November 13, 2017; Published: November 13, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award DE-SC0004993). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract DE-AC02-76SF00515. Pourbaix diagram computation was supported by the Materials Project (BES DOE Grant EDCBEE). Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract DE-AC02-05CH11231. We thank Apurva Mehta, Fang Ren, Douglas G. Van Campen, Tim Dunn, and Ryan Jones for assistance with collection of synchrotron XRD data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - acs.chemmater.7b03591.pdf
", "abstract": "Solar-driven oxygen evolution is a critical technology for renewably synthesizing hydrogen- and carbon-containing fuels in solar fuel generators. New photoanode materials are needed to meet efficiency and stability requirements, motivating materials explorations for semiconductors with (i) band-gap energy in the visible spectrum and (ii) stable operation in aqueous electrolyte at the electrochemical potential needed to evolve oxygen from water. Motivated by the oxygen evolution competency of many Mn-based oxides, the existence of several Bi-containing ternary oxide photoanode materials, and the variety of known oxide materials combining these elements with Sm, we explore the Bi\u2013Mn\u2013Sm oxide system for new photoanodes. Through the use of a ferri/ferrocyanide redox couple in high-throughput screening, BiMn_2O_5 and its alloy with Sm are identified as photoanode materials with a near-ideal optical band gap of 1.8 eV. Using density functional theory-based calculations of the mullite Bi^(3+)Mn^(3+)Mn^(4+)O_5 phase, we identify electronic analogues to the well-known BiVO4 photoanode and demonstrate excellent Pourbaix stability above the oxygen evolution Nernstian potential from pH 4.5 to 15. Our suite of experimental and computational characterization indicates that BiMn_2O_5 is a complex oxide with the necessary optical and chemical properties to be an efficient, stable solar fuel photoanode.", "date": "2017-12-12", "date_type": "published", "publication": "Chemistry of Materials", "volume": "29", "number": "23", "publisher": "American Chemical Society", "pagerange": "10027-10036", "id_number": "CaltechAUTHORS:20171115-095753143", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171115-095753143", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.chemmater.7b03591", "primary_object": { "basename": "acs.chemmater.7b03591.pdf", "url": "https://authors.library.caltech.edu/records/vz524-3yb66/files/acs.chemmater.7b03591.pdf" }, "pub_year": "2017", "author_list": "Newhouse, Paul F.; Reyes-Lillo, Sebastian E.; et el." }, { "id": "https://authors.library.caltech.edu/records/b556r-abz64", "eprint_id": 82634, "eprint_status": "archive", "datestamp": "2023-08-19 06:49:52", "lastmod": "2023-10-17 22:34:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-Arunima-K", "name": { "family": "Singh", "given": "Arunima K." }, "orcid": "0000-0002-7212-6310" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Montoya-J-H", "name": { "family": "Montoya", "given": "Joseph H." }, "orcid": "0000-0001-5760-2860" }, { "id": "Winston-D", "name": { "family": "Winston", "given": "Donald" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" } ] }, "title": "Electrochemical Stability of Metastable Materials", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: September 19, 2017; Revised: October 18, 2017; Published: October 24, 2017. \n\nThis work was primarily funded by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Computational work was additionally supported by the Materials Project (Grant No. EDCBEE) Predictive Modeling Center through the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02-05CH11231. Computational resources were provided by the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors thank Matthias Richter for assistance with collection of XPS data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cm7b03980_si_001.pdf
", "abstract": "We present a first-principles-based formalism to provide a quantitative measure of the thermodynamic instability and propensity for electrochemical stabilization, passivation, or corrosion of metastable materials in aqueous media. We demonstrate that this formalism can assess the relative Gibbs free energy of candidate materials in aqueous media as well as their decomposition products, combining solid and aqueous phases, as a function of pH and potential. On the basis of benchmarking against 20 stable as well as metastable materials reported in the literature and also our experimental characterization of metastable triclinic-FeVO_4, we present quantitative estimates for the relative Gibbs free energy and corresponding aqueous regimes where these materials are most likely to be stable, form inert passivating films, or steadily corrode to aqueous species. Furthermore, we show that the structure and composition of the passivating films formed on triclinic-FeVO_4 are also in excellent agreement with the Point Defect Model, as proposed by the corrosion community. An open-source web application based on the formalism is made available at https://materialsproject.org.", "date": "2017-12-12", "date_type": "published", "publication": "Chemistry of Materials", "volume": "29", "number": "23", "publisher": "American Chemical Society", "pagerange": "10159-10167", "id_number": "CaltechAUTHORS:20171024-154241789", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171024-154241789", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.chemmater.7b03980", "primary_object": { "basename": "cm7b03980_si_001.pdf", "url": "https://authors.library.caltech.edu/records/b556r-abz64/files/cm7b03980_si_001.pdf" }, "pub_year": "2017", "author_list": "Singh, Arunima K.; Zhou, Lan; et el." }, { "id": "https://authors.library.caltech.edu/records/h8b96-p2z29", "eprint_id": 83966, "eprint_status": "archive", "datestamp": "2023-08-19 06:20:46", "lastmod": "2023-10-18 14:34:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kirk-Charlotte", "name": { "family": "Kirk", "given": "Charlotte" } }, { "id": "Chen-Leanne-D", "name": { "family": "Chen", "given": "Leanne D." }, "orcid": "0000-0001-9700-972X" }, { "id": "Siahrostami-Samira", "name": { "family": "Siahrostami", "given": "Samira" }, "orcid": "0000-0002-1192-4634" }, { "id": "Karamad-Mohammadreza", "name": { "family": "Karamad", "given": "Mohammadreza" } }, { "id": "Bajdich-Michal", "name": { "family": "Bajdich", "given": "Michal" }, "orcid": "0000-0003-1168-8616" }, { "id": "Voss-Johannes", "name": { "family": "Voss", "given": "Johannes" }, "orcid": "0000-0001-7740-8811" }, { "id": "N\u00f8rskov-Jens-K", "name": { "family": "N\u00f8rskov", "given": "Jens K." }, "orcid": "0000-0002-4427-7728" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" } ] }, "title": "Theoretical Investigations of the Electrochemical Reduction of CO on Single Metal Atoms Embedded in Graphene", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: September 25, 2017; Published: December 18, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. C.K. acknowledges support from the NSF Graduate Research Fellowship program under Grant No. DGE-114747 and from the Morgridge Family Stanford Graduate Fellowship. L.D.C. acknowledges financial support from the Natural Sciences and Engineering Research Council of Canada for the CGS-D3 fellowship. \n\nThe authors declare no competing financial interest.\n\nPublished - acscentsci.7b00442.pdf
Supplemental Material - oc7b00442_si_001.pdf
", "abstract": "Single transition metal atoms embedded at single vacancies of graphene provide a unique paradigm for catalytic reactions. We present a density functional theory study of such systems for the electrochemical reduction of CO. Theoretical investigations of CO electrochemical reduction are particularly challenging in that electrochemical activation energies are a necessary descriptor of activity. We determined the electrochemical barriers for key proton\u2013electron transfer steps using a state-of-the-art, fully explicit solvent model of the electrochemical interface. The accuracy of GGA-level functionals in describing these systems was also benchmarked against hybrid methods. We find the first proton transfer to form CHO from CO to be a critical step in C_1 product formation. On these single atom sites, the corresponding barrier scales more favorably with the CO binding energy than for 211 and 111 transition metal surfaces, in the direction of improved activity. Intermediates and transition states for the hydrogen evolution reaction were found to be less stable than those on transition metals, suggesting a higher selectivity for CO reduction. We present a rate volcano for the production of methane from CO. We identify promising candidates with high activity, stability, and selectivity for the reduction of CO. This work highlights the potential of these systems as improved electrocatalysts over pure transition metals for CO reduction.", "date": "2017-12", "date_type": "published", "publication": "ACS Central Science", "volume": "3", "number": "12", "publisher": "American Chemical Society", "pagerange": "1286-1293", "id_number": "CaltechAUTHORS:20171219-112016737", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171219-112016737", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-114747" }, { "agency": "Stanford Graduate Fellowship" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)", "grant_number": "CGS-D3" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscentsci.7b00442", "pmcid": "PMC5746853", "primary_object": { "basename": "acscentsci.7b00442.pdf", "url": "https://authors.library.caltech.edu/records/h8b96-p2z29/files/acscentsci.7b00442.pdf" }, "related_objects": [ { "basename": "oc7b00442_si_001.pdf", "url": "https://authors.library.caltech.edu/records/h8b96-p2z29/files/oc7b00442_si_001.pdf" } ], "pub_year": "2017", "author_list": "Kirk, Charlotte; Chen, Leanne D.; et el." }, { "id": "https://authors.library.caltech.edu/records/0f51p-7sw75", "eprint_id": 83062, "eprint_status": "archive", "datestamp": "2023-08-19 06:17:10", "lastmod": "2023-10-17 22:53:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shing-Amanda-M", "name": { "family": "Shing", "given": "Amanda M." } }, { "id": "Tolstova-Y", "name": { "family": "Tolstova", "given": "Yulia" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Effects of surface condition on the work function and valence-band position of ZnSnN_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Springer-Verlag GmbH Germany. \n\nReceived: 17 May 2017; Accepted: 27 October 2017; First Online: 07 November 2017. \n\nWe gratefully acknowledge support from the Dow Chemical Company under the earth-abundant semiconductor project. We also acknowledge the Joint Center for Artificial Photosynthesis and the Molecular Materials Research Center of the Beckman Institute at Caltech for instrument access. The authors thank Bruce Brunschwig and Kimberly Papadantonakis for guidance. \n\nCompliance with ethical standards. \n\nFunding: Dow Chemical Company, Caltech Molecular Materials Research Center.\n\nSupplemental Material - 339_2017_1341_MOESM1_ESM.docx
", "abstract": "ZnSnN_2 is an emerging wide band gap earth-abundant semiconductor with potential applications in photonic devices such as solar cells, LEDs, and optical sensors. We report the characterization by ultraviolet photoelectron spectroscopy and X-ray photoelectron spectroscopy of reactively radio-frequency sputtered II\u2013IV-nitride ZnSnN_2 thin films. For samples transferred in high vacuum, the ZnSnN2 surface work function was 4.0\u2009\u00b1\u20090.1 eV below the vacuum level, with a valence-band onset of 1.2\u2009\u00b1\u20090.1 eV below the Fermi level. The resulting band diagram indicates that the degenerate bulk Fermi level position in ZnSnN_2 shifts to mid-gap at the surface due to band bending that results from equilibration with delocalized surface states within the gap. Brief (<\u200910 s) exposures to air, a nitrogen-plasma treatment, or argon-ion sputtering caused significant chemical changes at the surface, both in surface composition and interfacial energetics. The relative band positioning of the n-type semiconductor against standard redox potentials indicated that ZnSnN_2 has an appropriate energy band alignment for use as a photoanode to effect the oxygen-evolution reaction.", "date": "2017-12", "date_type": "published", "publication": "Applied Physics A: Materials Science and Processing", "volume": "123", "number": "12", "publisher": "Springer", "pagerange": "Art. No. 735", "id_number": "CaltechAUTHORS:20171108-094950631", "issn": "0947-8396", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171108-094950631", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow Chemical Company" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s00339-017-1341-3", "primary_object": { "basename": "339_2017_1341_MOESM1_ESM.docx", "url": "https://authors.library.caltech.edu/records/0f51p-7sw75/files/339_2017_1341_MOESM1_ESM.docx" }, "pub_year": "2017", "author_list": "Shing, Amanda M.; Tolstova, Yulia; et el." }, { "id": "https://authors.library.caltech.edu/records/6beq9-43852", "eprint_id": 83031, "eprint_status": "archive", "datestamp": "2023-08-19 06:11:00", "lastmod": "2023-10-23 15:10:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Paul-J-T", "name": { "family": "Paul", "given": "J. T." } }, { "id": "Singh-Arunima-K", "name": { "family": "Singh", "given": "A. K." }, "orcid": "0000-0002-7212-6310" }, { "id": "Dong-Zheng", "name": { "family": "Dong", "given": "Zheng" } }, { "id": "Zhuang-H", "name": { "family": "Zhuang", "given": "H." } }, { "id": "Revard-B-C", "name": { "family": "Revard", "given": "B. C." } }, { "id": "Rijal-B", "name": { "family": "Rijal", "given": "B." } }, { "id": "Ashton-M", "name": { "family": "Ashton", "given": "M." } }, { "id": "Linscheid-A", "name": { "family": "Linscheid", "given": "A." } }, { "id": "Blonsky-M", "name": { "family": "Blonsky", "given": "M." } }, { "id": "Gluhovic-D", "name": { "family": "Gluhovic", "given": "D." } }, { "id": "Guo-J", "name": { "family": "Guo", "given": "J." } }, { "id": "Hennig-R-G", "name": { "family": "Hennig", "given": "R. G." }, "orcid": "0000-0003-4933-7686" } ] }, "title": "Computational methods for 2D materials: discovery, property characterization, and application design", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 IOP Publishing Ltd. \n\nReceived 22 December 2016; Accepted 12 October 2017; Accepted Manuscript online 12 October 2017; Published 8 November 2017. \n\nThis work was supported by the National Science Foundation under grants Nos. DMR-1542776, ACI-1440547, and PHY-1549132, the Center for Bright Beams.\n\nThis work was supported by the National Science Foundation under grants Nos. DMR-1748464, DMR-1542776, ACI-1440547, and PHY-1549132, the Center for Bright Beams.", "abstract": "The discovery of two-dimensional (2D) materials comes at a time when computational methods are mature and can predict novel 2D materials, characterize their properties, and guide the design of 2D materials for applications. This article reviews the recent progress in computational approaches for 2D materials research. We discuss the computational techniques and provide an overview of the ongoing research in the field. We begin with an overview of known 2D materials, common computational methods, and available cyber infrastructures. We then move onto the discovery of novel 2D materials, discussing the stability criteria for 2D materials, computational methods for structure prediction, and interactions of monolayers with electrochemical and gaseous environments. Next, we describe the computational characterization of the 2D materials' electronic, optical, magnetic, and superconducting properties and the response of the properties under applied mechanical strain and electrical fields. From there, we move on to discuss the structure and properties of defects in 2D materials, and describe methods for 2D materials device simulations. We conclude by providing an outlook on the needs and challenges for future developments in the field of computational research for 2D materials.", "date": "2017-11-29", "date_type": "published", "publication": "Journal of Physics: Condensed Matter", "volume": "29", "number": "47", "publisher": "IOP", "pagerange": "Art. No. 473001", "id_number": "CaltechAUTHORS:20171107-111134229", "issn": "0953-8984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171107-111134229", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1542776" }, { "agency": "NSF", "grant_number": "ACI-1440547" }, { "agency": "NSF", "grant_number": "PHY-1549132" }, { "agency": "NSF", "grant_number": "DMR-1748464" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1088/1361-648X/aa9305", "pub_year": "2017", "author_list": "Paul, J. T.; Singh, A. K.; et el." }, { "id": "https://authors.library.caltech.edu/records/y85rf-07v48", "eprint_id": 78588, "eprint_status": "archive", "datestamp": "2023-08-21 22:14:34", "lastmod": "2023-10-26 00:12:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Jingjing", "name": { "family": "Jiang", "given": "Jingjing" } }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Poddar-R", "name": { "family": "Poddar", "given": "Rakesh" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan" }, "orcid": "0000-0001-5245-0538" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce" }, "orcid": "0000-0002-6135-6727" } ] }, "title": "Nanoelectrical and Nanoelectrochemical Imaging of Pt/p-Si and Pt/p+-Si Electrodes", "ispublished": "pub", "full_text_status": "public", "keywords": "afm; electrochemistry; energy conversion; interface; secm", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nIssue online: 23 November 2017; Version of record online: 7 August 2017; Accepted manuscript online: 21 June 2017; Manuscript Revised: 19 June 2017; Manuscript Received: 22 May 2017. \n\nFunded by: \nU.S. Department of Energy. Grant Number: DE-SC0004993;\nGordon and Betty Moore Foundation. Grant Number: GBMF1225.\n\nSupplemental Material - cssc201700893-sup-0001-SI1.pdf
", "abstract": "The interfacial properties of electrolessly deposited Pt nanoparticles (Pt-NP) on p-Si and p+-Si electrodes have been resolved on the nanometer scale using a combination of scanning probe methods. Atomic-force microscopy (AFM) showed highly dispersed Pt nanoparticles. Conductive AFM measurements showed that only about half of the particles exhibited measurable contact currents, with a factor of 10^3 difference in current. Local current-voltage measurements revealed a rectifying junction with a resistance of \u2265 10 M\u03a9 at the Pt-NP/p-Si interface, while Pt-NP/p+-Si samples formed an Ohmic junction with a local resistance of \u2265 1 M\u03a9. The particles were strongly attached to the sample surface in air. However in contact with an electrolyte, the adhesion of the particles to the surface was substantially lower. Scanning electrochemical microscopy (SECM) showed smaller, but more uniform electrochemical currents for the particles relative to the currents observed in conductive AFM measurements. In accord with the conductive AFM measurements, SECM measurements showed conductance through the substrate for only a minority of the particles. These results suggest that the electrochemical performance of the electrolessly deposited Pt nanoparticles on Si is ascribable to: 1) the high resistance of the contact between the particles and the substrate; 2) the low (<50%) fraction of particles that support high currents; and 3) the low adhesion of the particles to the surface in the electrolyte.", "date": "2017-11-23", "date_type": "published", "publication": "ChemSusChem", "volume": "10", "number": "22", "publisher": "Wiley", "pagerange": "4657-4663", "id_number": "CaltechAUTHORS:20170627-075439064", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170627-075439064", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201700893", "primary_object": { "basename": "cssc201700893-sup-0001-SI1.pdf", "url": "https://authors.library.caltech.edu/records/y85rf-07v48/files/cssc201700893-sup-0001-SI1.pdf" }, "pub_year": "2017", "author_list": "Jiang, Jingjing; Huang, Zhuangqun; et el." }, { "id": "https://authors.library.caltech.edu/records/afv6w-g0245", "eprint_id": 83390, "eprint_status": "archive", "datestamp": "2023-08-19 06:08:14", "lastmod": "2023-10-17 23:05:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lu-Yu-Jung", "name": { "family": "Lu", "given": "Yu-Jung" }, "orcid": "0000-0002-3932-653X" }, { "id": "Sokhoyan-Ruzan", "name": { "family": "Sokhoyan", "given": "Ruzan" }, "orcid": "0000-0003-4599-6350" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Kafaie-Shirmanesh-G", "name": { "family": "Kafaie Shirmanesh", "given": "Ghazaleh" }, "orcid": "0000-0003-1666-3215" }, { "id": "Davoyan-Artur-R", "name": { "family": "Davoyan", "given": "Artur R." }, "orcid": "0000-0002-4662-1158" }, { "id": "Pala-Ragip-A", "name": { "family": "Pala", "given": "Ragip A." } }, { "id": "Thyagarajan-Krishnan", "name": { "family": "Thyagarajan", "given": "Krishnan" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Dynamically controlled Purcell enhancement of visible spontaneous emission in a gated plasmonic heterostructure", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 The Authors. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived: 13 April 2017; Accepted: 20 October 2017; Published online: 21 November 2017. \n\nThis work was supported by Samsung Electronics, the Air Force Office of Scientific Research under grant number FA9550-16-1-0019 (device-related work), and the Department of Energy under grant number DE-FG02-07ER46405 (transparent conductor-related work). We also acknowledge use of facilities supported by the Kavli Nanoscience Institute (KNI) and the Joint Center for Artificial Photosynthesis (JCAP) at Caltech. Y.-J.L. acknowledges the support from Ministry of Science and Technology, Taiwan (Grant numbers: 104-2917-I-564-057). The authors would like to thank Wei-Hsiang Lin, Anya Mitskovets, and Panos Patsalas for useful discussions. The authors gratefully acknowledge Erin Burkett from the Hixon Writing Center at Caltech for providing feedback and guidance on writing during the revision process. The authors also deeply appreciate help in the form of the close reading of the manuscript and review responses by Kelly Mauser, Dagny Fleischman, Rebecca Glaudell, Haley Bauser, Cora Went, Phil Jahelka, and Michael Kelzenberg. \n\nContributions: Y.-J.L., R.S. and H.A.A. proposed the original idea. Y.-J.L. performed all experiments, calculations, and data analysis. R.S. proposed the theoretical model and performed calculations. R.P. and W.-H.C. helped with the optical setup. K.T., G.K.S., W.-H.C., and R.S. performed ellipsometry measurements and analyzed the ellipsometry data. A.R.D. helped in discussion. Y.-J.L., R.S., and H.A.A. wrote the paper, and all authors discussed and revised the final manuscript. \n\nThe authors declare no competing financial interests.\n\nPublished - s41467-017-01870-0.pdf
Supplemental Material - 41467_2017_1870_MOESM1_ESM.pdf
Supplemental Material - 41467_2017_1870_MOESM2_ESM.pdf
", "abstract": "Emission control of colloidal quantum dots (QDs) is a cornerstone of modern high-quality lighting and display technologies. Dynamic emission control of colloidal QDs in an optoelectronic device is usually achieved by changing the optical pump intensity or injection current density. Here we propose and demonstrate a distinctly different mechanism for the temporal modulation of QD emission intensity at constant optical pumping rate. Our mechanism is based on the electrically controlled modulation of the local density of optical states (LDOS) at the position of the QDs, resulting in the modulation of the QD spontaneous emission rate, far-field emission intensity, and quantum yield. We manipulate the LDOS via field effect-induced optical permittivity modulation of an ultrathin titanium nitride (TiN) film, which is incorporated in a gated TiN/SiO_2/Ag plasmonic heterostructure. The demonstrated electrical control of the colloidal QD emission provides a new approach for modulating intensity of light in displays and other optoelectronics.", "date": "2017-11-21", "date_type": "published", "publication": "Nature Communications", "volume": "8", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 1631", "id_number": "CaltechAUTHORS:20171121-092456068", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171121-092456068", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Samsung Electronics" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-16-1-0019" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "104-2917-I-564-057" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1038/s41467-017-01870-0", "pmcid": "PMC5696373", "primary_object": { "basename": "41467_2017_1870_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/afv6w-g0245/files/41467_2017_1870_MOESM1_ESM.pdf" }, "related_objects": [ { "basename": "41467_2017_1870_MOESM2_ESM.pdf", "url": "https://authors.library.caltech.edu/records/afv6w-g0245/files/41467_2017_1870_MOESM2_ESM.pdf" }, { "basename": "s41467-017-01870-0.pdf", "url": "https://authors.library.caltech.edu/records/afv6w-g0245/files/s41467-017-01870-0.pdf" } ], "pub_year": "2017", "author_list": "Lu, Yu-Jung; Sokhoyan, Ruzan; et el." }, { "id": "https://authors.library.caltech.edu/records/x6pm3-w2129", "eprint_id": 81674, "eprint_status": "archive", "datestamp": "2023-08-21 22:12:52", "lastmod": "2023-10-17 20:57:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fan-Zheng", "name": { "family": "Fan", "given": "Zheng" } }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Wang-Yiliu", "name": { "family": "Wang", "given": "Yiliu" } }, { "id": "Zhao-Zipeng", "name": { "family": "Zhao", "given": "Zipeng" } }, { "id": "Lin-Zhaoyang", "name": { "family": "Lin", "given": "Zhaoyang" }, "orcid": "0000-0002-6474-7184" }, { "id": "Cheng-Hung-Chieh", "name": { "family": "Cheng", "given": "Hung-Chieh" } }, { "id": "Lee-Sung-Joon", "name": { "family": "Lee", "given": "Sung-Joon" } }, { "id": "Wang-Gongming", "name": { "family": "Wang", "given": "Gongming" } }, { "id": "Feng-Ziying", "name": { "family": "Feng", "given": "Ziying" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" } ] }, "title": "Layer-by-Layer Degradation of Methylammonium Lead Tri-iodide Perovskite Microplates", "ispublished": "pub", "full_text_status": "public", "keywords": "hybrid perovskite; thermal stability; in situ TEM", "note": "\u00a9 2017 Elsevier B.V. \n\nReceived 15 June 2017, Revised 24 June 2017, Accepted 4 August 2017, Available online 20 September 2017. Published: September 20, 2017. \n\nX.D. acknowledges the support by National Science Foundation DMR1508144. Y.H. acknowledges the financial support from National Science Foundation EFRI-1433541. W.A.G. and H.X. acknowledge support by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award no. DE-SC0004993. \n\nAuthor Contributions: X.D., Y.H., and Z. Fan designed the research and experimental studies. W.A.G. and H.X. designed and conducted the theoretical studies. Z. Fan carried out the in situ HRTEM characterization. H.X. performed the theoretical calculations. Y.W., G.W., and Z.L. synthesized the material and conducted the XRD characterization. Z. Feng and Z.Z. analyzed the data. H.C.-C., S.-J.L., and Z. Fan prepared the hBN-perovskite-hBN heterostructure. X.D., Z. Fan, and H.X. wrote the manuscript. All the authors participated in discussions of the research.\n\nSupplemental Material - mmc1.pdf
", "abstract": "The methylammonium lead iodide (MAPbI3) perovskite has attracted considerable interest for its high-efficiency, low-cost solar cells, but is currently plagued by its poor environmental and thermal stability. To aid the development of robust devices, we investigate here the microscopic degradation pathways of MAPbI3 microplates. Using in situ transmission electron microscopy to follow the thermal degradation process, we find that under moderate heating at 85\u00b0C the crystalline structure shows a gradual evolution from tetragonal MAPbI3 to trigonal lead iodide layered crystals with a fixed crystallographic direction. Our solid-state nudged elastic band calculations confirm that the surface-initiated layer-by-layer degradation path exhibits the lowest energy barrier for crystal transition. We further show experimentally and theoretically that encapsulation of the perovskites with boron nitride flakes suppresses the surface degradation, greatly improving its thermal stability. These studies provide mechanistic insight into the thermal stability of perovskites that suggests new designs for improved stability.", "date": "2017-11-15", "date_type": "published", "publication": "Joule", "volume": "1", "number": "3", "publisher": "Elsevier", "pagerange": "548-562", "id_number": "CaltechAUTHORS:20170921-103249191", "issn": "2542-4351", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170921-103249191", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1508144" }, { "agency": "NSF", "grant_number": "EFRI-1433541" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.joule.2017.08.005", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/x6pm3-w2129/files/mmc1.pdf" }, "pub_year": "2017", "author_list": "Fan, Zheng; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/zk5wq-3n222", "eprint_id": 82210, "eprint_status": "archive", "datestamp": "2023-08-19 05:58:58", "lastmod": "2023-10-17 22:06:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Kun", "name": { "family": "Sun", "given": "Kun" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Wu-Lina", "name": { "family": "Wu", "given": "Lina" } }, { "id": "Hu-Yongfeng", "name": { "family": "Hu", "given": "Yongfeng" } }, { "id": "Zhou-Jigang", "name": { "family": "Zhou", "given": "Jigang" }, "orcid": "0000-0001-6644-2862" }, { "id": "MacLennan-A", "name": { "family": "MacLennan", "given": "Aimee" } }, { "id": "Jiang-Zhaohua", "name": { "family": "Jiang", "given": "Zhaohua" } }, { "id": "Zhaohua-Yunzhi", "name": { "family": "Gao", "given": "Yunzhi" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Wang-Zhijiang", "name": { "family": "Wang", "given": "Zhijiang" }, "orcid": "0000-0001-9314-7922" } ] }, "title": "Ultrahigh Mass Activity for Carbon Dioxide Reduction Enabled by Gold-iron Core-shell Nanoparticles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: August 30, 2017; Published: October 9, 2017. \n\nT.C. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DE-SC0004993. Z.W. acknowledges Mr. David Muir for his kind help on the EXAFS measurement and financial support from the National Natural Science Foundation of China (no. 51572062) and the Natural Science Foundation of Heilongjiang Province (no. B2015002). L.W. appreciates the financial support of National Natural Science Foundation of China (no. 81771903), Heilongjiang Province Foundation for Returness (no. LC2016034), and Wuliande Foundation of Harbin Medical University (grant no. WLD-QN1404). C.L.S. is supported by the NSERC, NRC, CIHR of Canada, and the University of Saskatchewan. The QM calculations used the resources of the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation grant no. ACI-1053575. \n\nThe authors declare no competing financial interest.\n\nPublished - jacs.7b09251
Submitted - ja-2017-092512-MS-oct8-Tao.pdf
Supplemental Material - ja7b09251_si_001.pdf
", "abstract": "Wide application of carbon dioxide (CO_2) electrochemical energy storage requires catalysts with high mass activity. Alloy catalysts can achieve superior performance to single metals while reducing the cost by finely tuning the composition and morphology. We used in silico quantum mechanics rapid screening to identify Au\u2013Fe as a candidate improving CO_2 reduction and then synthesized and tested it experimentally. The synthesized Au\u2013Fe alloy catalyst evolves quickly into a stable Au\u2013Fe core\u2013shell nanoparticle (AuFe-CSNP) after leaching out surface Fe. This AuFe-CSNP exhibits exclusive CO selectivity, long-term stability, nearly a 100-fold increase in mass activity toward CO_2 reduction compared with Au NP, and 0.2 V lower in overpotential. Calculations show that surface defects due to Fe leaching contribute significantly to decrease the overpotential.", "date": "2017-11-08", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "44", "publisher": "American Chemical Society", "pagerange": "15608-15611", "id_number": "CaltechAUTHORS:20171009-111707593", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171009-111707593", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51572062" }, { "agency": "Natural Science Foundation of Heilongjiang Province", "grant_number": "B2015002" }, { "agency": "National Natural Science Foundation of China", "grant_number": "81771903" }, { "agency": "Heilongjiang Province Foundation for Returness", "grant_number": "LC2016034" }, { "agency": "Wuliande Foundation of Harbin Medical University", "grant_number": "WLD-QN1404" }, { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "National Research Council of Canada" }, { "agency": "Canadian Institutes of Health Research (CIHR)" }, { "agency": "University of Saskatchewan" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.7b09251", "primary_object": { "basename": "ja-2017-092512-MS-oct8-Tao.pdf", "url": "https://authors.library.caltech.edu/records/zk5wq-3n222/files/ja-2017-092512-MS-oct8-Tao.pdf" }, "related_objects": [ { "basename": "ja7b09251_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zk5wq-3n222/files/ja7b09251_si_001.pdf" }, { "basename": "jacs.7b09251", "url": "https://authors.library.caltech.edu/records/zk5wq-3n222/files/jacs.7b09251" } ], "pub_year": "2017", "author_list": "Sun, Kun; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/h0akd-0vb06", "eprint_id": 76835, "eprint_status": "archive", "datestamp": "2023-08-21 22:03:20", "lastmod": "2023-10-25 16:54:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Operando X-ray photoelectron spectroscopic investigations of the electrochemical double layer at Ir/KOH(aq) interfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Electrochemical double layer; Operando XPS; Solid/liquid interface", "note": "\u00a9 2017 Elsevier B.V. \n\nReceived 11 November 2016, Revised 19 February 2017, Accepted 17 March 2017, Available online 18 March 2017.", "abstract": "Tender X-ray operando photoemission spectroscopy has been used to directly analyze the energetics of the double layer at a metal-water interface in a dilute electrolyte having a Debye length of several nanometers. The data are compared to a theoretical evaluation of the potential of the solution near the electrode. Due to its noble nature, Ir was chosen as a working electrode material, and KOH(aq) at varied concentrations and thicknesses constituted the electrolyte. Shifts in peak width and binding energy of the water O 1s core level were analyzed by modeling based on Debye-H\u00fcckel approximations. The data are consistent with electrochemical formulations of the double layer that provide a foundation to electrochemistry.", "date": "2017-11", "date_type": "published", "publication": "Journal of Electron Spectroscopy and Related Phenomena", "volume": "221", "publisher": "Elsevier", "pagerange": "99-105", "id_number": "CaltechAUTHORS:20170424-080421711", "issn": "0368-2048", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170424-080421711", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.elspec.2017.03.011", "pub_year": "2017", "author_list": "Lichterman, Michael F.; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/z5qmb-j4d84", "eprint_id": 81445, "eprint_status": "archive", "datestamp": "2023-08-19 05:37:12", "lastmod": "2023-10-17 19:51:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Singh-Arunima-K", "name": { "family": "Singh", "given": "Arunima K." }, "orcid": "0000-0002-7212-6310" }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Discovery of Manganese-Based Solar Fuel Photoanodes via Integration of Electronic Structure Calculations, Pourbaix Stability Modeling, and High-Throughput Experiments", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: July 10, 2017; Accepted: September 7, 2017; Published: September 7, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Computational work was additionally supported by the Materials Project (Grant No. EDCBEE) through the U.S. Department of Energy (DOE), Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02-05CH11231. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. DOE under Contract DE-AC02-05CH11231. Computational resources were also provided by the DOE through the National Energy Supercomputing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz7b00607_si_001.pdf
", "abstract": "The solar photoelectrochemical generation of hydrogen and carbon-containing fuels comprises a critical energy technology for establishing sustainable energy resources. The photoanode, which is responsible for solar-driven oxygen evolution, has persistently limited technology advancement due to the lack of materials that exhibit both the requisite electronic properties and operational stability. Efforts to extend the lifetime of solar fuel devices increasingly focus on mitigating corrosion in the highly oxidizing oxygen evolution environment, motivating our development of a photoanode discovery pipeline that combines electronic structure calculations, Pourbaix stability screening, and high-throughput experiments. By applying the pipeline to ternary metal oxides containing manganese, we identify a promising class of corrosion-resistant materials and discover five oxygen evolution photoanodes, including the first demonstration of photoelectrocatalysis with Mn-based ternary oxides and the introduction of alkaline earth manganates as promising photoanodes for establishing a durable solar fuels technology.", "date": "2017-10-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "2", "number": "10", "publisher": "American Chemical Society", "pagerange": "2307-2312", "id_number": "CaltechAUTHORS:20170914-131954119", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170914-131954119", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1021/acsenergylett.7b00607", "primary_object": { "basename": "nz7b00607_si_001.pdf", "url": "https://authors.library.caltech.edu/records/z5qmb-j4d84/files/nz7b00607_si_001.pdf" }, "pub_year": "2017", "author_list": "Shinde, Aniketa; Suram, Santosh K.; et el." }, { "id": "https://authors.library.caltech.edu/records/bdphm-9mf52", "eprint_id": 81242, "eprint_status": "archive", "datestamp": "2023-08-19 05:37:04", "lastmod": "2023-10-17 19:41:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wiensch-J-D", "name": { "family": "Wiensch", "given": "Joshua D." }, "orcid": "0000-0002-8235-6937" }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Velazquez-J-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Pieterick-A-P", "name": { "family": "Pieterick", "given": "Adam P." } }, { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Zhao-Xinghao", "name": { "family": "Zhao", "given": "Xinghao" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Comparative Study in Acidic and Alkaline Media of the Effects of pH and Crystallinity on the Hydrogen-Evolution Reaction on MoS_2 and MoSe_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: August 4, 2017; Accepted: August 28, 2017; Published: September 6, 2017. \n\nJ.J. thanks the Camille and Henry Dreyfus Foundation for support through its postdoctoral fellowship program in environmental chemistry. This material is based upon work supported by the U.S. Department of Energy, Office of Basic Energy Sciences under Award No. DE-FG02-03ER15483. J.M.V. acknowledges support through an NRC Ford Foundation Postdoctoral Fellowship. D.A.T. acknowledges support through the NSF Graduate Research Fellowships Program. Single-crystal MoS2 growth and sputtering of Mo was performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. X-ray photoelectron spectroscopy was performed at the Molecular Materials Research Center of the Beckman Institute at Caltech.\n\nSupplemental Material - nz7b00700_si_001.pdf
", "abstract": "Single crystals of n-type MoS_2 and n-MoSe_2 showed higher electrocatalytic activity for the evolution of H_2(g) in alkaline solutions than in acidic solutions. The overpotentials required to drive hydrogen evolution at \u221210 mA cm^(\u20132) of current density for MoS^2 samples were \u22120.76 \u00b1 0.13 and \u22121.03 \u00b1 0.21 V when in contact with 1.0 M NaOH(aq) and 1.0 M H_2SO_4(aq), respectively. For MoSe_2 samples, the overpotentials at \u221210 mA cm^(\u20132) were \u22120.652 \u00b1 0.050 and \u22120.709 \u00b1 0.073 V in contact with 1.0 M KOH(aq) and 1.0 M H_2SO_4(aq), respectively. Single crystals from two additional sources were also tested, and the absolute values of the measured overpotentials were consistently less (by 460 \u00b1 250 mV) in alkaline solutions than in acidic solutions. When electrochemical etching was used to create edge sites on the single crystals, the kinetics improved in acid but changed little in alkaline media. The overpotentials measured for polycrystalline thin films (PTFs) and amorphous forms of MoS_2 showed less sensitivity to pH and edge density than was observed for single crystals and showed enhanced kinetics in acid when compared to alkaline solutions. These results suggest that the active sites for hydrogen evolution on MoS_2 and MoSe_2 are different in alkaline and acidic media. Thus, while edges are known to serve as active sites in acidic media, in alkaline media it is more likely that terraces function in this role.", "date": "2017-10-13", "date_type": "published", "publication": "ACS Energy Letters", "volume": "2", "number": "10", "publisher": "American Chemical Society", "pagerange": "2234-2238", "id_number": "CaltechAUTHORS:20170907-124508456", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170907-124508456", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "NRC Ford Foundation Postdoctoral Fellowship" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.7b00700", "primary_object": { "basename": "nz7b00700_si_001.pdf", "url": "https://authors.library.caltech.edu/records/bdphm-9mf52/files/nz7b00700_si_001.pdf" }, "pub_year": "2017", "author_list": "Wiensch, Joshua D.; John, Jimmy; et el." }, { "id": "https://authors.library.caltech.edu/records/px460-w3x39", "eprint_id": 79526, "eprint_status": "archive", "datestamp": "2023-08-19 05:32:59", "lastmod": "2023-10-26 16:16:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ulissi-Z-W", "name": { "family": "Ulissi", "given": "Zachary W." }, "orcid": "0000-0002-9401-4918" }, { "id": "Tang-Michael-T", "name": { "family": "Tang", "given": "Michael T." } }, { "id": "Xiao-Jianping", "name": { "family": "Xiao", "given": "Jianping" }, "orcid": "0000-0003-1779-6140" }, { "id": "Liu-Xinyan", "name": { "family": "Liu", "given": "Xinyan" } }, { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Karamad-M", "name": { "family": "Karamad", "given": "Mohammadreza" } }, { "id": "Cummins-K-D", "name": { "family": "Cummins", "given": "Kyle" } }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" }, { "id": "Norskov-J-K", "name": { "family": "Norskov", "given": "Jens K." } } ] }, "title": "Machine-Learning Methods Enable Exhaustive Searches for Active Bimetallic Facets and Reveal Active Site Motifs for CO_2 Reduction", "ispublished": "pub", "full_text_status": "public", "keywords": "density functional theory, bimetallic facets, machine learning, catalysis, electrochemistry, CO2 reduction,\nmachine learning, DFT, energy", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: May 20, 2017; Revised: July 17, 2017; Published: July 27, 2017.\n\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. D.A.T. and M.T acknowledge graduate fellowships through the National Science Foundation Graduate Research Fellowship under Grant No. DGE-114747.\n\nThe authors declare no competing financial interests.\n\nSupplemental Material - cs7b01648_si_001.pdf
", "abstract": "Bimetallic catalysts are promising for the most difficult thermal and electrochemical reactions, but modeling the many diverse active sites on polycrystalline samples is an open challenge. We present a general framework for addressing this complexity in a systematic and predictive fashion. Active sites for every stable low-index facet of a bimetallic crystal are enumerated and cataloged, yielding hundreds of possible active sites. The activity of these sites is explored in parallel using a neural-network-based surrogate model to share information between the many density functional theory (DFT) relaxations, resulting in activity estimates with an order of magnitude fewer explicit DFT calculations. Sites with interesting activity were found and provide targets for follow-up calculations. This process was applied to the electrochemical reduction of CO_2 on nickel gallium bimetallics and indicated that most facets had similar activity to Ni surfaces, but a few exposed Ni sites with a very favorable on-top CO configuration. This motif emerged naturally from the predictive modeling and represents a class of intermetallic CO_2 reduction catalysts. These sites rationalize recent experimental reports of nickel gallium activity and why previous materials screens missed this exciting material. Most importantly these methods suggest that bimetallic catalysts will be discovered by studying facet reactivity and diversity of active sites more systematically.", "date": "2017-10-06", "date_type": "published", "publication": "ACS Catalysis", "volume": "7", "number": "10", "publisher": "American Chemical Society", "pagerange": "6600-6608", "id_number": "CaltechAUTHORS:20170728-081606737", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170728-081606737", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-114747" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.7b01648", "primary_object": { "basename": "cs7b01648_si_001.pdf", "url": "https://authors.library.caltech.edu/records/px460-w3x39/files/cs7b01648_si_001.pdf" }, "pub_year": "2017", "author_list": "Ulissi, Zachary W.; Tang, Michael T.; et el." }, { "id": "https://authors.library.caltech.edu/records/rdtkq-g8k55", "eprint_id": 81265, "eprint_status": "archive", "datestamp": "2023-08-19 05:29:28", "lastmod": "2023-10-17 19:42:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Moreno-Hernandez-I-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "MacFarland-C-A", "name": { "family": "MacFarland", "given": "Clara A." }, "orcid": "0000-0002-9570-948X" }, { "id": "Read-C-G", "name": { "family": "Read", "given": "Carlos G." } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Crystalline nickel manganese antimonate as a stable water-oxidation catalyst in aqueous 1.0 M H_2SO_4", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Royal Society of Chemistry. \n\nThe article was received on 28 May 2017, accepted on 10 Aug 2017 and first published on 10 Aug 2017. \n\nThis work is supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. I. M. H. acknowledges a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469. This work was also supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. C. G. R. acknowledges the Resnick Sustainability Institute for a post-doctoral fellowship. We thank N. Dalleska and P. Buabthong for assistance with mass spectroscopy measurements and X-ray photoelectron spectroscopy measurements, respectively.\n\nSupplemental Material - c7ee01486d1.pdf
", "abstract": "Water oxidation is a required half-reaction for electrochemical water splitting. To date, the only well-established active oxygen-evolution catalysts stable under operating conditions and at rest in acidic aqueous media contain Ru or Ir, two of the scarcest non-radioactive elements on Earth. We report herein a nickel-manganese antimonate electrocatalyst with a rutile-type crystal structure that requires an initial voltammetric overpotential of 672 \u00b1 9 mV to catalyze the oxidation of water to O_2(g) at a rate corresponding to 10 mA cm^(\u22122) of current density when operated in contact with 1.0 M sulfuric acid. Under galvanostatic control, the overpotential initially rose from 670 mV but was then stable at 735 \u00b1 10 mV for 168 h of continuous operation at 10 mA cm^(\u22122). We additionally provide an in-depth evaluation of the stability of the nickel-manganese antimonate electrocatalyst, including elemental characterization of the surface, bulk, and electrolyte before and after electrochemical operation.", "date": "2017-10-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "2017", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2103-2108", "id_number": "CaltechAUTHORS:20170908-102102710", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170908-102102710", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C7EE01486D", "primary_object": { "basename": "c7ee01486d1.pdf", "url": "https://authors.library.caltech.edu/records/rdtkq-g8k55/files/c7ee01486d1.pdf" }, "pub_year": "2017", "author_list": "Moreno-Hernandez, Ivan A.; MacFarland, Clara A.; et el." }, { "id": "https://authors.library.caltech.edu/records/6t5ab-dff07", "eprint_id": 80895, "eprint_status": "archive", "datestamp": "2023-08-19 05:10:14", "lastmod": "2023-10-17 18:34:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Drisdell-Walter-S", "name": { "family": "Drisdell", "given": "Walter S." }, "orcid": "0000-0002-8693-4562" }, { "id": "Gul-Sheraz", "name": { "family": "Gul", "given": "Sheraz" }, "orcid": "0000-0001-8920-8737" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Operando Spectroscopic Analysis of CoP Films Electrocatalyzing the Hydrogen-Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: July 20, 2017; Published: August 28, 2017. \n\nThis work was based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the U.S. Department of Energy Office of Science under Award Number DE-SC0004993. Synchrotron measurements were performed at beamlines 7-3 and 14-3 at the Stanford Synchrotron Radiation Lightsource at SLAC National Accelerator Laboratory, which is operated by Stanford University for the U.S. Department of Energy Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-76SF00515, and supported by the Office of Biological and Environmental Research, and by the NIH including P41GM103393. A.I.C. acknowledges a Graduate Research Fellowship from the National Science Foundation. The authors gratefully acknowledge R. Jones and Dr. K. Walczak for assistance with spectroelectrochemical cell fabrication. \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - ja7b07606_si_001.pdf
", "abstract": "Transition metal phosphides exhibit high catalytic activity towards the electrochemical hydrogen-evolution reaction (HER) and resist chemical corrosion in acidic solutions. For example, an electrodeposited CoP catalyst exhibited an overpotential, \u03b7, of -\u03b7 < 100 mV at a current density of -10 mA cm^(-2) in 0.500 M H_2SO_4(aq). To obtain a chemical description of the material as-prepared and also while effecting the HER in acidic media, such electrocatalyst films were investigated using Raman spectroscopy and X-ray absorption spectroscopy both ex-situ as well as under in-situ and operando conditions in 0.500 M H_2SO_4(aq). Ex-situ analysis using the tandem spectroscopies indicated the presence of multiple ordered and disordered phases that contained both near-zero valent and oxidized Co species, in addition to reduced and oxygenated P species. Operando analysis indicated that the active electrocatalyst was primarily amorphous and predominantly consisted of near-zero-valent Co as well as reduced P.", "date": "2017-09-20", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "37", "publisher": "American Chemical Society", "pagerange": "12927-12930", "id_number": "CaltechAUTHORS:20170829-095313751", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170829-095313751", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "NIH", "grant_number": "P41GM103393" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.7b07606", "primary_object": { "basename": "ja7b07606_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6t5ab-dff07/files/ja7b07606_si_001.pdf" }, "pub_year": "2017", "author_list": "Saadi, Fadl H.; Carim, Azhar I.; et el." }, { "id": "https://authors.library.caltech.edu/records/v2h89-znz21", "eprint_id": 80460, "eprint_status": "archive", "datestamp": "2023-08-19 05:05:43", "lastmod": "2023-10-17 16:00:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Tsuchiya-Takashi", "name": { "family": "Tsuchiya", "given": "Takashi" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Linear-response time-dependent embedded mean-field theory", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: June 27, 2017; Published: August 7, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. T.F.M. and F.D. additionally acknowledge support from the Air Force Office of Scientific Research under Award Number FA9550-17-1-0102, and T.F.M. acknowledges support from a Camille Dreyfus Teacher-Scholar Award. F.R.M. and T.T. acknowledge support from the Engineering and Physical Sciences Research Council (EP/M013111/1).\n\nSupplemental Material - ct7b00666_si_001.pdf
", "abstract": "We present a time-dependent (TD) linear-response description of excited electronic states within the framework of embedded mean-field theory (EMFT). TD-EMFT allows for subsystems to be described at different mean-field levels of theory, enabling straightforward treatment of excited states and transition properties. We provide benchmark demonstrations of TD-EMFT for both local and nonlocal excitations in organic molecules, as well as applications to chlorophyll a, solvatochromic shifts of a dye in solution, and sulfur K-edge X-ray absorption spectroscopy (XAS). It is found that mixed-basis implementations of TD-EMFT lead to substantial errors in terms of transition properties; however, as previously found for ground-state EMFT, these errors are largely eliminated with the use of Fock-matrix corrections. These results indicate that TD-EMFT is a promising method for the efficient, multilevel description of excited-state electronic structure and dynamics in complex systems.", "date": "2017-09-12", "date_type": "published", "publication": "Journal of Chemical Theory and Computation", "volume": "13", "number": "9", "publisher": "American Chemical Society", "pagerange": "4216-4227", "id_number": "CaltechAUTHORS:20170816-075909755", "issn": "1549-9618", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170816-075909755", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-17-1-0102" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jctc.7b00666", "primary_object": { "basename": "ct7b00666_si_001.pdf", "url": "https://authors.library.caltech.edu/records/v2h89-znz21/files/ct7b00666_si_001.pdf" }, "pub_year": "2017", "author_list": "Ding, Feizhi; Tsuchiya, Takashi; et el." }, { "id": "https://authors.library.caltech.edu/records/8hj1b-93x52", "eprint_id": 80471, "eprint_status": "archive", "datestamp": "2023-08-19 04:47:42", "lastmod": "2023-10-17 16:01:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Nature of the active sites for CO reduction on copper nanoparticles; suggestions for optimizing performance", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: April 2, 2017; Published: August 16, 2017. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This computational work used the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by National Science Foundation grant number ACI-1053575, and the Zwicky Astrophysics Supercomputer at Caltech. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja7b03300_si_001.pdf
", "abstract": "Recent experiments show that the grain boundaries (GBs) of copper nanoparticles (NP) lead to outstanding performance in reducing CO_2 and CO to alcohol products. We report here multiscale simulations that mimic experimental synthesis conditions to predict the structure of a 10nm Cu NP (158,555 atoms). To identify active sites, we first predict the CO binding at a large number of sites and select 4 exhibiting CO binding stronger than the (211) step surface. Then, we predict the formation energy of *OCCOH intermediate as a descriptor for C-C coupling, identifying two active sites, both of which have an undercoordinated surface square site adjacent to a subsurface stacking fault. We then propose a periodic Cu surface (4 by 4 supercell) with a similar site that substantially decreases the formation energy of *OCCOH, by 0.14 eV.", "date": "2017-08-30", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "34", "publisher": "American Chemical Society", "pagerange": "11642-11645", "id_number": "CaltechAUTHORS:20170816-091808789", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170816-091808789", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.7b03300", "primary_object": { "basename": "ja7b03300_si_001.pdf", "url": "https://authors.library.caltech.edu/records/8hj1b-93x52/files/ja7b03300_si_001.pdf" }, "pub_year": "2017", "author_list": "Cheng, Tao; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/9q310-2n919", "eprint_id": 79307, "eprint_status": "archive", "datestamp": "2023-08-19 04:44:06", "lastmod": "2023-10-26 14:47:35", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Han-Zhiji", "name": { "family": "Han", "given": "Zhiji" }, "orcid": "0000-0001-9349-1571" }, { "id": "Kortlever-Ruud", "name": { "family": "Kortlever", "given": "Ruud" } }, { "id": "Chen-Hsiang-Yun", "name": { "family": "Chen", "given": "Hsiang-Yun" }, "orcid": "0000-0002-6461-1519" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "CO_2 Reduction Selective for C_(\u22652) Products on Polycrystalline Copper with N-Substituted Pyridinium Additives", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: April 26, 2017; Published: July 21, 2017. \n\nNMR and XPS spectra were collected at the NMR Facility (Division of CCE) and Molecular Materials Research Center (Beckman Institute) of the California Institute of Technology, respectively. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nPublished - acscentsci.7b00180.pdf
Supplemental Material - oc7b00180_si_001.pdf
Supplemental Material - oc7b00180_si_002.cif
", "abstract": "Electrocatalytic CO_2 reduction to generate multicarbon products is of interest for applications in artificial photosynthetic schemes. This is a particularly attractive goal for CO_2 reduction by copper electrodes, where a broad range of hydrocarbon products can be generated but where selectivity for C\u2013C coupled products relative to CH_4 and H_2 remains an impediment. Herein we report a simple yet highly selective catalytic system for CO_2 reduction to C_(\u22652) hydrocarbons on a polycrystalline Cu electrode in bicarbonate aqueous solution that uses N-substituted pyridinium additives. Selectivities of 70\u201380% for C_2 and C_3 products with a hydrocarbon ratio of C_(\u22652)/CH4significantly greater than 100 have been observed with several additives. ^(13)C-labeling studies verify CO_2 to be the sole carbon source in the C_(\u22652) hydrocarbons produced. Upon electroreduction, the N-substituted pyridinium additives lead to film deposition on the Cu electrode, identified in one case as the reductive coupling product of N-arylpyridinium. Product selectivity can also be tuned from C_(\u22652) species to H_2 (\u223c90%) while suppressing methane with certain N-heterocyclic additives.", "date": "2017-08-23", "date_type": "published", "publication": "ACS Central Science", "volume": "3", "number": "8", "publisher": "American Chemical Society", "pagerange": "853-859", "id_number": "CaltechAUTHORS:20170724-131758454", "issn": "2374-7943", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170724-131758454", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscentsci.7b00180", "pmcid": "PMC5571460", "primary_object": { "basename": "acscentsci.7b00180.pdf", "url": "https://authors.library.caltech.edu/records/9q310-2n919/files/acscentsci.7b00180.pdf" }, "related_objects": [ { "basename": "oc7b00180_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9q310-2n919/files/oc7b00180_si_001.pdf" }, { "basename": "oc7b00180_si_002.cif", "url": "https://authors.library.caltech.edu/records/9q310-2n919/files/oc7b00180_si_002.cif" } ], "pub_year": "2017", "author_list": "Han, Zhiji; Kortlever, Ruud; et el." }, { "id": "https://authors.library.caltech.edu/records/kk0j3-azx13", "eprint_id": 72189, "eprint_status": "archive", "datestamp": "2023-08-21 21:36:18", "lastmod": "2023-10-23 18:01:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Thyagarajan-K", "name": { "family": "Thyagarajan", "given": "Krishnan" } }, { "id": "Sokhoyan-R", "name": { "family": "Sokhoyan", "given": "Ruzan" }, "orcid": "0000-0003-4599-6350" }, { "id": "Zornberg-L-Z", "name": { "family": "Zornberg", "given": "Leonardo Z." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Millivolt Modulation of Plasmonic Metasurface Optical Response via Ionic Conductance", "ispublished": "pub", "full_text_status": "public", "keywords": "filament formation; indium tin oxide (ITO); ionic transport; memristors; tunable metasurfaces", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nVersion of record online: 14 June 2017; Manuscript Revised: 28 April 2017; Manuscript Received: 21 February 2017. \n\nThis work was supported by the Swiss National Science Foundation (Grant No. 151853), Hybrid Nanophotonics Multidisciplinary University Research Initiative Grant (Air Force Office of Scientific Research, FA9550-12-1-0024), and the Samsung Electronics Metaphotonics Cluster. The conducting oxide material synthesis design and characterization was supported by the U.S. Department of Energy (DOE), Office of Science Grant (DE-FG02-07ER46405). Used facilities were supported by the Kavli Nanoscience Institute (KNI) and Joint Center for Artificial Photosynthesis (JCAP) at Caltech. The authors would like to thank Artur R. Davoyan, Matthew Sullivan Hunt, and Barry Baker for useful discussions; Carol Garland for help with the TEM imaging; and Jonathan Grandidier for his help with the transfer matrix code. \n\nThe authors declare no conflict of interest.\n\nSubmitted - 1607.03391.pdf
Supplemental Material - adma201701044-sup-0001-S1.pdf
", "abstract": "A plasmonic metasurface with an electrically tunable optical response that operates at strikingly low modulation voltages is experimentally demonstrated. The fabricated metasurface shows up to 30% relative change in reflectance in the visible spectral range upon application of 5 mV and 78% absolute change in reflectance upon application of 100 mV of bias. The designed metasurface consists of nanostructured silver and indium tin oxide (ITO) electrodes which are separated by 5 nm thick alumina. The millivolt-scale optical modulation is attributed to a new modulation mechanism, in which transport of silver ions through alumina dielectric leads to bias-induced nucleation and growth of silver nanoparticles in the ITO counter-electrode, altering the optical extinction response. This transport mechanism, which occurs at applied electric fields of 1 mV nm^(\u22121), provides a new approach to use of ionic transport for electrical control over light\u2013matter interactions.", "date": "2017-08-18", "date_type": "published", "publication": "Advanced Materials", "volume": "29", "number": "31", "publisher": "Wiley", "pagerange": "Art. No. 1701044", "id_number": "CaltechAUTHORS:20161121-085049515", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161121-085049515", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "151853" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0024" }, { "agency": "Samsung Electronics" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1002/adma.201701044", "primary_object": { "basename": "1607.03391.pdf", "url": "https://authors.library.caltech.edu/records/kk0j3-azx13/files/1607.03391.pdf" }, "related_objects": [ { "basename": "adma201701044-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/kk0j3-azx13/files/adma201701044-sup-0001-S1.pdf" } ], "pub_year": "2017", "author_list": "Thyagarajan, Krishnan; Sokhoyan, Ruzan; et el." }, { "id": "https://authors.library.caltech.edu/records/jesh2-qz122", "eprint_id": 79478, "eprint_status": "archive", "datestamp": "2023-08-19 04:41:15", "lastmod": "2023-10-26 16:14:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Resasco-J", "name": { "family": "Resasco", "given": "Joaquin" } }, { "id": "Chen-Leanne-D", "name": { "family": "Chen", "given": "Leanne D." }, "orcid": "0000-0001-9700-972X" }, { "id": "Clark-E", "name": { "family": "Clark", "given": "Ezra" } }, { "id": "Tsai-Charlie", "name": { "family": "Tsai", "given": "Charlie" } }, { "id": "Hahn-C", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" }, { "id": "Chan-Karen", "name": { "family": "Chan", "given": "Karen" }, "orcid": "0000-0002-6897-1108" }, { "id": "Bell-A-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" } ] }, "title": "Promoter effects of alkali metal cations on the electrochemical reduction of carbon dioxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: June 29, 2017; Published: July 24, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. J.R. gratefully acknowledges support of the National Science Foundation Graduate Research Fellowship Program (NSF GRFP) under Grant No. DGE-0802270. The authors would also like to acknowledge the allocation of computer time at the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja7b06765_si_001.pdf
", "abstract": "The electrochemical reduction of CO_2 is known to be influenced by the identity of the alkali metal cation in the electrolyte; however, a satisfactory explanation for this phenomenon has not been developed. Here we present the results of experimental and theoretical studies aimed at elucidating the effects of electrolyte cation size on the intrinsic activity and selectivity of metal catalysts for the reduction of CO_2. Experiments were conducted under conditions where the influence of electrolyte polarization is minimal in order to show that cation size affects the intrinsic rates of formation of certain reaction products, most notably for HCOO\u2013, C_2H_4, and C_2H_5OH over Cu(100)- and Cu(111)-oriented thin films, and for CO and HCOO\u2013 over polycrystalline Ag and Sn. Interpretation of the findings for CO_2 reduction was informed by studies of the reduction of glyoxal and CO, key intermediates along the reaction pathway to final products. Density functional theory calculations show that the alkali metal cations influence the distribution of products formed as a consequence of electrostatic interactions between solvated cations present at the outer Helmholtz plane and adsorbed species having large dipole moments. The observed trends in activity with cation size are attributed to an increase in the concentration of cations at the outer Helmholtz plane with increasing cation size.", "date": "2017-08-16", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "32", "publisher": "American Chemical Society", "pagerange": "11277-11287", "id_number": "CaltechAUTHORS:20170727-084953058", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170727-084953058", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-0802270" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.7b06765", "primary_object": { "basename": "ja7b06765_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jesh2-qz122/files/ja7b06765_si_001.pdf" }, "pub_year": "2017", "author_list": "Resasco, Joaquin; Chen, Leanne D.; et el." }, { "id": "https://authors.library.caltech.edu/records/syh64-cbm50", "eprint_id": 78766, "eprint_status": "archive", "datestamp": "2023-08-19 04:37:24", "lastmod": "2023-10-26 00:22:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jhalani-V-A", "name": { "family": "Jhalani", "given": "Vatsal A." }, "orcid": "0000-0003-0866-0858" }, { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Ultrafast Hot Carrier Dynamics in GaN and its Impact on the Efficiency Droop", "ispublished": "pub", "full_text_status": "public", "keywords": "Gallium nitride, light emitting diodes, ultrafast dynamics, electron-phonon scattering", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: May 25, 2017; Revised: July 20, 2017; Published: July 24, 2017. \n\nV.J. thanks the Resnick Sustainibility Institute at Caltech for fellowship support. J.-J.Z. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of the computational methods employed in this work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. M.B. acknowledges support by the National Science Foundation under Grant No. ACI-1642443, which provided for basic theory and part of the electronphonon coupling code development. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors thank Davide Sangalli for fruitful discussions. \n\nAuthor Contributions: M.B. conceived and designed the research. V.J. and J.-J.Z. developed the computational codes and carried out the calculations. All authors wrote the manuscript. \n\nThe authors declare no competing financial interest.\n\nAccepted Version - acs.nanolett.7b02212_acc.pdf
Submitted - 1703.07880.pdf
Supplemental Material - nl7b02212_si_001.pdf
", "abstract": "GaN is a key material for lighting technology. Yet, the carrier transport and ultrafast dynamics that are central in GaN light-emitting devices are not completely understood. We present first-principles calculations of carrier dynamics in GaN, focusing on electron\u2013phonon (e-ph) scattering and the cooling and nanoscale dynamics of hot carriers. We find that e-ph scattering is significantly faster for holes compared to electrons and that for hot carriers with an initial 0.5\u20131 eV excess energy, holes take a significantly shorter time (\u223c0.1 ps) to relax to the band edge compared to electrons, which take \u223c1 ps. The asymmetry in the hot carrier dynamics is shown to originate from the valence band degeneracy, the heavier effective mass of holes compared to electrons, and the details of the coupling to different phonon modes in the valence and conduction bands. We show that the slow cooling of hot electrons and their long ballistic mean free paths (over 3 nm at room temperature) are a possible cause of efficiency droop in GaN light-emitting diodes. Taken together, our work sheds light on the ultrafast dynamics of hot carriers in GaN and the nanoscale origin of efficiency droop.", "date": "2017-08-09", "date_type": "published", "publication": "Nano Letters", "volume": "17", "number": "8", "publisher": "American Chemical Society", "pagerange": "5012-5019", "id_number": "CaltechAUTHORS:20170705-124137567", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170705-124137567", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1642443" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.nanolett.7b02212", "primary_object": { "basename": "1703.07880.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/1703.07880.pdf" }, "related_objects": [ { "basename": "acs.nanolett.7b02212_acc.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/acs.nanolett.7b02212_acc.pdf" }, { "basename": "nl7b02212_si_001.pdf", "url": "https://authors.library.caltech.edu/records/syh64-cbm50/files/nl7b02212_si_001.pdf" } ], "pub_year": "2017", "author_list": "Jhalani, Vatsal A.; Zhou, Jin-Jian; et el." }, { "id": "https://authors.library.caltech.edu/records/psbz3-f5d17", "eprint_id": 70797, "eprint_status": "archive", "datestamp": "2023-08-19 04:15:59", "lastmod": "2023-10-20 23:31:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mauser-Kelly-W", "name": { "family": "Mauser", "given": "Kelly W." } }, { "id": "Kim-Seyoon", "name": { "family": "Kim", "given": "Seyoon" }, "orcid": "0000-0002-8040-9521" }, { "id": "Mitrovic-Slobodan", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Fleischman-Dagny", "name": { "family": "Fleischman", "given": "Dagny" } }, { "id": "Pala-Ragip-A", "name": { "family": "Pala", "given": "Ragip A." } }, { "id": "Schwab-K-C", "name": { "family": "Schwab", "given": "K. C." }, "orcid": "0000-0001-8216-4815" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Resonant Thermoelectric Nanophotonics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Macmillan Publishers Limited, part of Springer Nature. \n\nReceived 10 June 2016; Accepted 31 March 2017; Published online 22 May 2017. \n\nThis work was supported primarily by the US Department of Energy (DOE) Office of Science grant DE-FG02-07ER46405. S.K. acknowledges support by a Samsung Scholarship. The authors thank M. Jones for discussions. \n\nAuthor Contributions: K.W.M. and H.A.A. conceived the ideas. K.W.M. and S.K. performed the simulations. K.W.M. fabricated the samples. K.W.M. built the measurement set-ups specific to this study. K.W.M., S.M. and D.F. performed measurements, and K.W.M., S.K. and S.M. performed data analysis. K.S. contributed to the design and analysis of noise measurements. R.P. built a general-use measurement set-up and provided assistance with part of one supplementary measurement. K.W.M., H.A.A. and S.M. co-wrote the paper. All authors discussed the results and commented on the manuscript, and H.A.A. supervised the project. \n\nThe authors declare no competing financial interests.\n\nSubmitted - 1606.03313.pdf
Supplemental Material - nnano.2017.87-s1.pdf
", "abstract": "Photodetectors are typically based either on photocurrent generation from electron\u2013hole pairs in semiconductor structures or on bolometry for wavelengths that are below bandgap absorption. In both cases, resonant plasmonic and nanophotonic structures have been successfully used to enhance performance. Here, we show subwavelength thermoelectric nanostructures designed for resonant spectrally selective absorption, which creates large localized temperature gradients even with unfocused, spatially uniform illumination to generate a thermoelectric voltage. We show that such structures are tunable and are capable of wavelength-specific detection, with an input power responsivity of up to 38 V\u2009W^(\u20131), referenced to incident illumination, and bandwidth of nearly 3 kHz. This is obtained by combining resonant absorption and thermoelectric junctions within a single suspended membrane nanostructure, yielding a bandgap-independent photodetection mechanism. We report results for both bismuth telluride/antimony telluride and chromel/alumel structures as examples of a potentially broader class of resonant nanophotonic thermoelectric materials for optoelectronic applications such as non-bandgap-limited hyperspectral and broadband photodetectors.", "date": "2017-08", "date_type": "published", "publication": "Nature Nanotechnology", "volume": "12", "number": "8", "publisher": "Nature Publishing Group", "pagerange": "770-775", "id_number": "CaltechAUTHORS:20161004-090725146", "issn": "1748-3387", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161004-090725146", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Samsung Scholarship" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1038/NNANO.2017.87", "primary_object": { "basename": "1606.03313.pdf", "url": "https://authors.library.caltech.edu/records/psbz3-f5d17/files/1606.03313.pdf" }, "related_objects": [ { "basename": "nnano.2017.87-s1.pdf", "url": "https://authors.library.caltech.edu/records/psbz3-f5d17/files/nnano.2017.87-s1.pdf" } ], "pub_year": "2017", "author_list": "Mauser, Kelly W.; Kim, Seyoon; et el." }, { "id": "https://authors.library.caltech.edu/records/rqxqj-yd609", "eprint_id": 80663, "eprint_status": "archive", "datestamp": "2023-08-19 04:20:12", "lastmod": "2023-10-17 17:04:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Taeyong", "name": { "family": "Kim", "given": "Taeyong" } }, { "id": "Ding-Ding", "name": { "family": "Ding", "given": "Ding" } }, { "id": "Yim-Jong-Hyuk", "name": { "family": "Yim", "given": "Jong-Hyuk" } }, { "id": "Jho-Young-Dahl", "name": { "family": "Jho", "given": "Young-Dahl" } }, { "id": "Minnich-A-J", "name": { "family": "Minnich", "given": "Austin J." }, "orcid": "0000-0002-9671-9540" } ] }, "title": "Elastic and thermal properties of free-standing molybdenum disulfide membranes measured using ultrafast transient grating spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).\n\nReceived 25 April 2017; accepted 2 August 2017; published online 21 August 2017. \n\nThis work was supported by the \"GIST-Caltech Research Collaboration\" Project through a grant provided by Gwangju Institute of Science and Technology in 2017. T.K. acknowledges the support by the Jeongsong Cultural Foundation (South Korea). D.D. gratefully acknowledges the support by the Agency for Science, Technology and Research (Singapore). The authors thank Stefan Omelchenko, Dr. Ke Sun, Dr. Hang Zhang, and Dr. Dennis Friedrich for experimental assistance, and Dr. Bo Sun and Andrew B. Robbins for the constructive discussions. The authors also gratefully acknowledge the use of equipment from the Caltech Joint Center for Artificial Photosynthesis (JCAP).\n\nPublished - 1_2E4999225.pdf
", "abstract": "Molybdenum disulfide (MoS_2), a member of transition-metal dichalcogenide family, is of intense interest due to its unique electronic and thermoelectric properties. However, reports of its in-plane thermal conductivity vary due to the difficulty of in-plane thermal conductivity measurements on thin films, and an experimental measurement of the in-plane sound velocity has not been reported. Here, we use time-resolved transient grating spectroscopy to simultaneously measure the in-plane elastic and thermal properties of free-standing MoS_2 membranes at room temperature. We obtain a longitudinal acoustic phonon velocity of 7000 \u00b1 40 m s^(\u22121) and an in-plane thermal conductivity of 74 \u00b1 21 W m^(\u22121)K^(\u22121). Our measurements provide useful insights into the elastic and thermal properties of MoS_2 and demonstrate the capability of transient grating spectroscopy to investigate the in-plane vibrational properties of van der Waals materials that are challenging to characterize with conventional methods.", "date": "2017-08", "date_type": "published", "publication": "APL Materials", "volume": "5", "number": "8", "publisher": "American Institute of Physics", "pagerange": "Art. No. 086105", "id_number": "CaltechAUTHORS:20170822-070843697", "issn": "2166-532X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170822-070843697", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "GIST-Caltech Research Collaboration" }, { "agency": "Jeongsong Cultural Foundation (South Korea)" }, { "agency": "Agency for Science, Technology and Research (A*STAR)" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1063/1.4999225", "primary_object": { "basename": "1_2E4999225.pdf", "url": "https://authors.library.caltech.edu/records/rqxqj-yd609/files/1_2E4999225.pdf" }, "pub_year": "2017", "author_list": "Kim, Taeyong; Ding, Ding; et el." }, { "id": "https://authors.library.caltech.edu/records/a867x-k7h27", "eprint_id": 78791, "eprint_status": "archive", "datestamp": "2023-08-19 04:11:40", "lastmod": "2023-10-26 00:23:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard III", "given": "William A." }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Predicted Structures of the Active Sites Responsible for the Improved Reduction of Carbon Dioxide by Gold Nanoparticles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: May 29, 2017; Accepted: July 4, 2017; Published: July 4, 2017. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment (XSEDE) which is supported by National Science Foundation grant number ACI-1053575, and the Zwicky Astrophysics supercomputer at Caltech.\n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jz-2017-013355-SI-FRO-wag.docx
Supplemental Material - jz7b01335_si_001.pdf
", "abstract": "Gold (Au) nanoparticles (NPs) are known experimentally to reduce carbon dioxide (CO_2) to carbon monoxide (CO), with far superior performance to Au foils. To obtain guidance in designing improved CO_2 catalysts, we want to understand the nature of the active sites on Au NPs. Here, we employed multiscale atomistic simulations to computationally synthesize and characterize a 10 nm thick Au NP on a carbon nanotube (CNT) support, and then we located active sites from quantum mechanics (QM) calculations on 269 randomly selected sites. The standard scaling relation is that the formation energy of *COOH (\u0394E_(*COOH)) is proportional to the binding energy of *CO (E^(binding)_(*CO)); therefore, decreasing \u0394E_(*COOH) to boost the CO_2 reduction reaction (CO_2RR) causes an increase of E^(binding)_(*CO) that retards CO_2RR. We show that the NPs have superior CO_2RR because there are many sites at the twin boundaries that significantly break this scaling relation.", "date": "2017-07-20", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "8", "number": "14", "publisher": "American Chemical Society", "pagerange": "3317-3320", "id_number": "CaltechAUTHORS:20170706-080647539", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170706-080647539", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.7b01335", "primary_object": { "basename": "jz-2017-013355-SI-FRO-wag.docx", "url": "https://authors.library.caltech.edu/records/a867x-k7h27/files/jz-2017-013355-SI-FRO-wag.docx" }, "related_objects": [ { "basename": "jz7b01335_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a867x-k7h27/files/jz7b01335_si_001.pdf" } ], "pub_year": "2017", "author_list": "Cheng, Tao; Huang, Yufeng; et el." }, { "id": "https://authors.library.caltech.edu/records/13963-nrv72", "eprint_id": 79249, "eprint_status": "archive", "datestamp": "2023-08-21 21:21:32", "lastmod": "2023-10-26 14:44:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-J-P", "name": { "family": "Liu", "given": "J. P." } }, { "id": "Kirchhoff-J", "name": { "family": "Kirchhoff", "given": "J." } }, { "id": "Zhou-L", "name": { "family": "Zhou", "given": "L." } }, { "id": "Zhao-M", "name": { "family": "Zhao", "given": "M." } }, { "id": "Grapes-M-D", "name": { "family": "Grapes", "given": "M. D." } }, { "id": "Dale-D-S", "name": { "family": "Dale", "given": "D. S." } }, { "id": "Tate-M-D", "name": { "family": "Tate", "given": "M. D." } }, { "id": "Philipp-H-T", "name": { "family": "Philipp", "given": "H. T." } }, { "id": "Gruner-S-M", "name": { "family": "Gruner", "given": "S. M." } }, { "id": "Weihs-T-P", "name": { "family": "Weihs", "given": "T. P." } }, { "id": "Hufnagel-T-C", "name": { "family": "Hufnagel", "given": "T. C." } } ] }, "title": "X-ray reflectivity measurement of interdiffusion in metallic multilayers during rapid heating", "ispublished": "pub", "full_text_status": "public", "keywords": "X-ray reflectivity; multilayer; interdiffusion", "note": "\u00a9 2017 International Union of Crystallography. This is an open-access article distributed under the terms of the Creative Commons Attribution (CC-BY) Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are cited. \n\nReceived 16 December 2016; Accepted 30 May 2017. \n\nJK, MZ, LZ, TPW and TCH gratefully acknowledge support for this work from the US Department of Energy under grant No. DE-SC002509. JPL gratefully acknowledges financial support from the Chinese Scholarship Council (CSC). This work is based upon research conducted at the Cornell High Energy Synchrotron Source (CHESS) which is supported by the National Science Foundation and the National Institutes of Health/National Institute of General Medical Sciences under NSF award DMR-1332208. Detector development at Cornell is supported by the DOE Grant No. DE-SC0016035 and CHESS.\n\nPublished - rx5034.pdf
", "abstract": "A technique for measuring interdiffusion in multilayer materials during rapid heating using X-ray reflectivity is described. In this technique the sample is bent to achieve a range of incident angles simultaneously, and the scattered intensity is recorded on a fast high-dynamic-range mixed-mode pixel array detector. Heating of the multilayer is achieved by electrical resistive heating of the silicon substrate, monitored by an infrared pyrometer. As an example, reflectivity data from Al/Ni heated at rates up to 200 K s^(\u22121) are presented. At short times the interdiffusion coefficient can be determined from the rate of decay of the reflectivity peaks, and it is shown that the activation energy for interdiffusion is consistent with a grain boundary diffusion mechanism. At longer times the simple analysis no longer applies because the evolution of the reflectivity pattern is complicated by other processes, such as nucleation and growth of intermetallic phases.", "date": "2017-07", "date_type": "published", "publication": "Journal of Synchrotron Radiation", "volume": "24", "number": "4", "publisher": "International Union of Crystallography", "pagerange": "796-801", "id_number": "CaltechAUTHORS:20170720-101438771", "issn": "1600-5775", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170720-101438771", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC002509" }, { "agency": "Chinese Scholarship Council" }, { "agency": "NSF", "grant_number": "DMR-1332208" }, { "agency": "NIH" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0016035" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1107/S1600577517008013", "primary_object": { "basename": "rx5034.pdf", "url": "https://authors.library.caltech.edu/records/13963-nrv72/files/rx5034.pdf" }, "pub_year": "2017", "author_list": "Liu, J. P.; Kirchhoff, J.; et el." }, { "id": "https://authors.library.caltech.edu/records/xk1je-hhe34", "eprint_id": 78138, "eprint_status": "archive", "datestamp": "2023-08-21 21:17:09", "lastmod": "2023-10-25 23:47:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Favaro-Marco", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Crumlin-Ethan-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" } ] }, "title": "Subsurface oxide plays a critical role in CO\u2082 activation by Cu(111) surfaces to form chemisorbed CO\u2082, the first step in reduction of CO\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "CO\u2082 reduction; suboxide copper; ambient pressure XPS; density functional theory; M06L", "note": "\u00a9 2017 National Academy of Sciences. Freely available online through the PNAS open access option. \n\nContributed by William A. Goddard III, May 9, 2017 (sent for review January 26, 2017; reviewed by Charles T. Campbell and Bruce E. Koel). \n\nThis work was supported through the Office of Science, Office of Basic Energy Science (BES), of the US Department of Energy (DOE) under Award DE-SC0004993 to the Joint Center for Artificial Photosynthesis and as part of the Joint Center for Energy Storage Research, DOE Energy Innovation Hubs. The Advanced Light Source is supported by the Director, Office of Science, Office of BES, of the US DOE under Contract DE-AC02-05CH11231. The QM calculations were carried out on the Zwicky supercomputer at Caltech. \n\nM.F. and H.X. contributed equally to this work. \n\nAuthor contributions: M.F., H.X., T.C., W.A.G., J.Y., and E.J.C. designed research, performed research, analyzed data, and wrote the paper. \n\nReviewers: C.T.C., University of Washington; and B.E.K., Princeton University. \n\nThe authors declare no conflict of interest. \n\nThis article contains Supporting Information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1701405114/-/DCSupplemental.\n\nPublished - PNAS-2017-Favaro-6706-11.pdf
Supplemental Material - pnas.201701405SI.pdf
", "abstract": "A national priority is to convert CO\u2082 into high-value chemical products such as liquid fuels. Because current electrocatalysts are not adequate, we aim to discover new catalysts by obtaining a detailed understanding of the initial steps of CO\u2082 electroreduction on copper surfaces, the best current catalysts. Using ambient pressure X-ray photoelectron spectroscopy interpreted with quantum mechanical prediction of the structures and free energies, we show that the presence of a thin suboxide structure below the copper surface is essential to bind the CO\u2082 in the physisorbed configuration at 298 K, and we show that this suboxide is essential for converting to the chemisorbed CO\u2082 in the presence of water as the first step toward CO\u2082 reduction products such as formate and CO. This optimum suboxide leads to both neutral and charged Cu surface sites, providing fresh insights into how to design improved carbon dioxide reduction catalysts.", "date": "2017-06-27", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "26", "publisher": "National Academy of Sciences", "pagerange": "6706-6711", "id_number": "CaltechAUTHORS:20170613-075002945", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170613-075002945", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1701405114", "pmcid": "PMC5495248", "primary_object": { "basename": "PNAS-2017-Favaro-6706-11.pdf", "url": "https://authors.library.caltech.edu/records/xk1je-hhe34/files/PNAS-2017-Favaro-6706-11.pdf" }, "related_objects": [ { "basename": "pnas.1701405114.sd01.pdf", "url": "https://authors.library.caltech.edu/records/xk1je-hhe34/files/pnas.1701405114.sd01.pdf" }, { "basename": "pnas.201701405SI.pdf", "url": "https://authors.library.caltech.edu/records/xk1je-hhe34/files/pnas.201701405SI.pdf" } ], "pub_year": "2017", "author_list": "Favaro, Marco; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/xqe4r-g7n57", "eprint_id": 78146, "eprint_status": "archive", "datestamp": "2023-08-21 21:17:27", "lastmod": "2023-10-25 23:48:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" } ] }, "title": "Cu metal embedded in oxidized matrix catalyst to promote CO\u2082 activation and CO dimerization for electrochemical reduction of CO\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "electrochemical reduction of CO\u2082; Cu metal embedded in oxidized matrix; density functional theory; CO\u2082 activation; CO dimerization", "note": "\u00a9 2017 National Academy of Sciences. Freely available online through the PNAS open access option. \n\nContributed by William A. Goddard III, May 9, 2017 (sent for review February 13, 2017; reviewed by Timo Jacob and Bruce Parkinson). \n\nThis research was supported by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. This work used the computational resources of Zwicky (at California Institute of Technology). \n\nAuthor contributions: H.X. and W.A.G. designed research; H.X. and T.C. performed research; H.X., W.A.G., T.C., and Y.L. analyzed data; and H.X. and W.A.G. wrote the paper. \n\nReviewers: T.J., Universit\u00e4t Ulm; and B.P., University of Wyoming. \n\nThe authors declare no conflict of interest. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1702405114/-/DCSupplemental.\n\nPublished - PNAS-2017-Xiao-6685-8.pdf
Supplemental Material - pnas.201702405SI.pdf
", "abstract": "We propose and validate with quantum mechanics methods a unique catalyst for electrochemical reduction of CO\u2082 (CO\u2082RR) in which selectivity and activity of CO and C\u2082 products are both enhanced at the borders of oxidized and metallic surface regions. This Cu metal embedded in oxidized matrix (MEOM) catalyst is consistent with observations that Cu\u2082O-based electrodes improve performance. However, we show that a fully oxidized matrix (FOM) model would not explain the experimentally observed performance boost, and we show that the FOM is not stable under CO\u2082 reduction conditions. This electrostatic tension between the Cu\u207a and Cu\u2070 surface sites responsible for the MEOM mechanism suggests a unique strategy for designing more efficient and selective electrocatalysts for CO\u2082RR to valuable chemicals (HCO\u2093), a critical need for practical environmental and energy applications.", "date": "2017-06-27", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "26", "publisher": "National Academy of Sciences", "pagerange": "6685-6688", "id_number": "CaltechAUTHORS:20170613-083147382", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170613-083147382", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1073/pnas.1702405114", "pmcid": "PMC5495255", "primary_object": { "basename": "PNAS-2017-Xiao-6685-8.pdf", "url": "https://authors.library.caltech.edu/records/xqe4r-g7n57/files/PNAS-2017-Xiao-6685-8.pdf" }, "related_objects": [ { "basename": "pnas.201702405SI.pdf", "url": "https://authors.library.caltech.edu/records/xqe4r-g7n57/files/pnas.201702405SI.pdf" } ], "pub_year": "2017", "author_list": "Xiao, Hai; Goddard, William A.; et el." }, { "id": "https://authors.library.caltech.edu/records/mhfm6-yh591", "eprint_id": 77805, "eprint_status": "archive", "datestamp": "2023-08-19 03:42:55", "lastmod": "2023-10-25 23:28:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "He-Lingyun", "name": { "family": "He", "given": "Lingyun" } }, { "id": "Zhou-Wu", "name": { "family": "Zhou", "given": "Wu" } }, { "id": "Cai-Dongping", "name": { "family": "Cai", "given": "Dongping" } }, { "id": "Mao-Samuel-S", "name": { "family": "Mao", "given": "Samuel S." } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Shen-Shaohua", "name": { "family": "Shen", "given": "Shaohua" }, "orcid": "0000-0001-8536-7386" } ] }, "title": "Pulsed laser-deposited n-Si/NiO_x photoanodes for stable and efficient photoelectrochemical water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 The Royal Society of Chemistry. \n\nReceived 19th January 2017; Accepted 14th May 2017; First published on 15 May 2017. \n\nThe authors gratefully acknowledge the financial support from the National Natural Science Foundation of China (51672210, 51323011 and 51236007), the Program for New Century Excellent Talents in University (NCET-13-0455), the Natural Science Foundation of Shaanxi Province (2014KW07-02), the Natural Science Foundation of Jiangsu Province (BK 20141212) and the Nano Research Program of Suzhou City (ZXG201442). S. Shen is supported by the Foundation for the Author of National Excellent Doctoral Dissertation of P. R. China (201335), the National Program for Support of Top-notch Young Professionals, and the \"Fundamental Research Funds for the Central Universities\". S. S. Mao acknowledges the support from the Shenzhen Peacock Plan (No. 1208040050847074).\n\nSupplemental Material - c7cy00114b1_si.pdf
", "abstract": "An electrocatalytic and stable nickel oxide (NiO_x) thin layer was successfully deposited on an n-Si (100) substrate by pulsed laser deposition (PLD), acting as a photoanode for efficient photo-oxidation of water under solar illumination. It was revealed that the formed n-Si/NiO_x heterojunction with good Schottky contact could improve photogenerated charge separation, and thus n-Si photoanodes deposited with a 105 nm-thick NiO_x electrocatalytic layer exhibited a photovoltage of \u223c350 mV, leading to greatly improved photoelectrochemical performances for water oxidation. The stability of the photoanode was significantly enhanced with the increasing thickness of NiO_x protective layers. This study demonstrates a simple and effective method to enable the use of planar n-Si (100) substrates as efficient and durable photoanodes for practical solar water oxidation.", "date": "2017-06-21", "date_type": "published", "publication": "Catalysis Science and Technology", "volume": "7", "number": "12", "publisher": "Royal Society of Chemistry", "pagerange": "2632-2638", "id_number": "CaltechAUTHORS:20170526-095044384", "issn": "2044-4753", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170526-095044384", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "51672210" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51323011" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51236007" }, { "agency": "Program for New Century Excellent Talents in University", "grant_number": "NCET-13-0455" }, { "agency": "Natural Science Foundation of Shaanxi Province", "grant_number": "2014KW07-02" }, { "agency": "Natural Science Foundation of Jiangsu Province", "grant_number": "BK 20141212" }, { "agency": "Nano Research Program of Suzhou City", "grant_number": "ZXG201442" }, { "agency": "Foundation for the Author of National Excellent Doctoral Dissertation", "grant_number": "201335" }, { "agency": "National Program for Support of Top-notch Young Professionals" }, { "agency": "Fundamental Research Funds for the Central Universities" }, { "agency": "Shenzhen Peacock Plan", "grant_number": "1208040050847074" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c7cy00114b", "primary_object": { "basename": "c7cy00114b1_si.pdf", "url": "https://authors.library.caltech.edu/records/mhfm6-yh591/files/c7cy00114b1_si.pdf" }, "pub_year": "2017", "author_list": "He, Lingyun; Zhou, Wu; et el." }, { "id": "https://authors.library.caltech.edu/records/re5ed-qja29", "eprint_id": 77630, "eprint_status": "archive", "datestamp": "2023-08-21 21:13:32", "lastmod": "2023-10-25 23:18:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hahn-Christopher", "name": { "family": "Hahn", "given": "Christopher" }, "orcid": "0000-0002-2772-6341" }, { "id": "Hatsukade-Toru", "name": { "family": "Hatsukade", "given": "Toru" }, "orcid": "0000-0001-9016-0929" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Vailionis-Arturas", "name": { "family": "Vailionis", "given": "Arturas" }, "orcid": "0000-0001-5878-1864" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." }, "orcid": "0000-0002-9210-344X" }, { "id": "Higgins-Drew-C", "name": { "family": "Higgins", "given": "Drew C." }, "orcid": "0000-0002-0585-2670" }, { "id": "Nitopi-Stephanie-A", "name": { "family": "Nitopi", "given": "Stephanie A." }, "orcid": "0000-0001-6815-0628" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Jaramillo-Thomas-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "Engineering Cu surfaces for the electrocatalytic conversion of CO_2: Controlling selectivity toward oxygenates and hydrocarbons", "ispublished": "pub", "full_text_status": "public", "keywords": "carbon dioxide reduction; epitaxy; electrocatalysis; copper", "note": "\u00a9 2017 National Academy of Sciences. \n\nEdited by Jean-Michel Sav\u00e9ant, Universit\u00e9 Paris Diderot, Paris, France, and approved April 10, 2017 (received for review November 16, 2016). Published online before print May 22, 2017. \n\nWe thank Dr. Jakob Kibsgaard and Dr. Karen Chan for their assistance in constructing the Cu surface structure models. Additional thanks go to the Stanford NMR Facility. Part of this work was performed at the Stanford Nano Shared Facilities (SNSF) and the Stanford Nanofabrication Facility (SNF), supported by the National Science Foundation under Award ECCS-1542152. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Innovation Hub, as follows: the development of electrochemical testing of Cu thin films was supported through the Office of Science of the US DOE under Award DE-SC0004993; the development of epitaxial growth was supported by the Global Climate Energy Project at Stanford University; the procurement of the physical vapor deposition chamber was supported by the DOE, Laboratory Directed Research and Development funding under Award DE-AC02-76SF00515. \n\nAuthor contributions: C.H., T.H., Y.-G.K., A.V., J.H.B., D.C.H., S.A.N., M.P.S., and T.F.J. designed research; C.H., T.H., Y.-G.K., A.V., J.H.B., D.C.H., and S.A.N. performed research; C.H., T.H., Y.-G.K., A.V., J.H.B., D.C.H., S.A.N., M.P.S., and T.F.J. analyzed data; C.H., T.H., Y.-G.K., A.V., J.H.B., D.C.H., S.A.N., M.P.S., and T.F.J. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1618935114/-/DCSupplemental.\n\nPublished - PNAS-2017-Hahn-5918-23.pdf
Supplemental Material - pnas.201618935SI.pdf
", "abstract": "In this study we control the surface structure of Cu thin-film catalysts to probe the relationship between active sites and catalytic activity for the electroreduction of CO_2 to fuels and chemicals. Here, we report physical vapor deposition of Cu thin films on large-format (\u223c6 cm^2) single-crystal substrates, and confirm epitaxial growth in the <100>, <111>, and <751> orientations using X-ray pole figures. To understand the relationship between the bulk and surface structures, in situ electrochemical scanning tunneling microscopy was conducted on Cu(100), (111), and (751) thin films. The studies revealed that Cu(100) and (111) have surface adlattices that are identical to the bulk structure, and that Cu(751) has a heterogeneous kinked surface with (110) terraces that is closely related to the bulk structure. Electrochemical CO_2 reduction testing showed that whereas both Cu(100) and (751) thin films are more active and selective for C\u2013C coupling than Cu(111), Cu(751) is the most selective for >2e\u2212 oxygenate formation at low overpotentials. Our results demonstrate that epitaxy can be used to grow single-crystal analogous materials as large-format electrodes that provide insights on controlling electrocatalytic activity and selectivity for this reaction.", "date": "2017-06-06", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "23", "publisher": "National Academy of Sciences", "pagerange": "5918-5923", "id_number": "CaltechAUTHORS:20170522-125149776", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170522-125149776", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ECCS-1542152" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Stanford University" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1618935114", "pmcid": "PMC5468660", "primary_object": { "basename": "PNAS-2017-Hahn-5918-23.pdf", "url": "https://authors.library.caltech.edu/records/re5ed-qja29/files/PNAS-2017-Hahn-5918-23.pdf" }, "related_objects": [ { "basename": "pnas.201618935SI.pdf", "url": "https://authors.library.caltech.edu/records/re5ed-qja29/files/pnas.201618935SI.pdf" } ], "pub_year": "2017", "author_list": "Hahn, Christopher; Hatsukade, Toru; et el." }, { "id": "https://authors.library.caltech.edu/records/6h4r2-e4a93", "eprint_id": 79534, "eprint_status": "archive", "datestamp": "2023-08-21 21:06:15", "lastmod": "2023-10-26 16:16:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ledina-M-A", "name": { "family": "Ledina", "given": "M. A." } }, { "id": "Bui-N-Khai", "name": { "family": "Bui", "given": "N." } }, { "id": "Liang-X", "name": { "family": "Liang", "given": "X." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Y.-G." }, "orcid": "0000-0002-5936-6520" }, { "id": "Jung-J", "name": { "family": "Jung", "given": "J." } }, { "id": "Perdue-B", "name": { "family": "Perdue", "given": "B." } }, { "id": "Tsang-C", "name": { "family": "Tsang", "given": "C." } }, { "id": "Drnec-J", "name": { "family": "Drnec", "given": "J." } }, { "id": "Carl\u00e0-F", "name": { "family": "Carl\u00e0", "given": "F." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "M. P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Reber-T-J", "name": { "family": "Reber", "given": "T. J." } }, { "id": "Stickney-J-L", "name": { "family": "Stickney", "given": "J. L." } } ] }, "title": "Electrochemical Formation of Germanene: pH 4.5", "ispublished": "pub", "full_text_status": "public", "keywords": "EC-STM; Electrodeposition; Germanene; Raman spectroscopy; Surface X-ray Diffraction", "note": "\u00a9 2017 The Author(s). Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial No Derivatives 4.0 License (CC BY-NC-ND, http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial reuse, distribution, and reproduction in any medium, provided the original work is not changed in any way and is properly cited. \n\nManuscript submitted March 9, 2017; Revised manuscript received May 8, 2017; Published May 27, 2017. \n\nThis was Paper 1313 presented at the Chicago, Illinois, Meeting of the Society, May 24\u201328, 2015. \n\nSupport from the National Science Foundation, DMR #1410109, is gratefully acknowledged, in addition to support from the National Science Foundation grant CHE-1214152 and by the Gordon and Betty Moore Foundation (GBMF1225). The research was in part carried out through the Joint Center for Artificial Photosynthesis at the California Institute of Technology, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, which provided support for Y.-G.K. and M.P.S. to perform the EC-STM experiments. We thank Dr. Resta from the Synchrotron Soleil, L'Orme des Merisiers, for his contributions to this work.\n\nPublished - J._Electrochem._Soc.-2017-Ledina-D469-77.pdf
", "abstract": "Germanene is a single layer allotrope of Ge, with a honeycomb structure similar to graphene. This report concerns the electrochemical formation of germanene in a pH 4.5 solution. The studies were performed using in situ Electrochemical Scanning Tunneling Microscopy (EC-STM), voltammetry, coulometry, surface X-ray diffraction (SXRD) and Raman spectroscopy to study germanene electrodeposition on Au(111) terraces. The deposition of Ge is kinetically slow and stops after 2\u20133 monolayers. EC-STM revealed a honeycomb (HC) structure with a rhombic unit cell, 0.44 \u00b1 0.02 nm on a side, very close to that predicted for germanene in the literature. Ideally the HC structure is a continuous sheet, with six Ge atoms around each hole. However, only small domains, surrounded by defects, of this structure were observed in this study. The small coherence length and multiple rotations domains made direct observation with surface X-ray diffraction difficult. Raman spectroscopy was used to investigate the multi-layer Ge deposits. A peak near 290 cm^(\u22121), predicted to correspond to germanene, was observed on one particular area of the sample, while the rest resembled amorphous germanium. Electrochemical studies of germanene showed limited stability when exposed to oxygen.", "date": "2017-05-27", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "164", "number": "7", "publisher": "Electrochemical Society", "pagerange": "D469-D477", "id_number": "CaltechAUTHORS:20170728-101828067", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170728-101828067", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1410109" }, { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.1221707jes", "primary_object": { "basename": "J._Electrochem._Soc.-2017-Ledina-D469-77.pdf", "url": "https://authors.library.caltech.edu/records/6h4r2-e4a93/files/J._Electrochem._Soc.-2017-Ledina-D469-77.pdf" }, "pub_year": "2017", "author_list": "Ledina, M. A.; Bui, N.; et el." }, { "id": "https://authors.library.caltech.edu/records/vdgnv-gry63", "eprint_id": 75196, "eprint_status": "archive", "datestamp": "2023-08-21 21:05:39", "lastmod": "2023-10-25 14:50:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Lin-Meng", "name": { "family": "Lin", "given": "Meng" }, "orcid": "0000-0001-7785-749X" }, { "id": "Haussener-S", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" } ] }, "title": "Reliable Performance Characterization of Mediated Photocatalytic Water-Splitting Half Reactions", "ispublished": "pub", "full_text_status": "public", "keywords": "characterization; mediator; photocatalysis; titania; water splitting", "note": "\u00a9 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nIssue online: 22 May 2017; Version of record online: 16 March 2017; Accepted manuscript online: 30 January 2017; Manuscript Revised: 30 January 2017; Manuscript Received: 27 December 2016. \n\nFunded by: Schweizerischer Nationalfonds zur F\u00f6rderung der Wissenschaftlichen Forschung. Grant Number: 155876\n\nSupplemental Material - cssc201601901-sup-0001-misc_information.pdf
", "abstract": "Photocatalytic approaches using two sets of semiconductor particles and a pair of redox-shuttle mediators are considered as a safe and economic solution for solar water splitting. Here, accurate experimental characterization techniques for photocatalytic half reactions are reported, investigating the gas as well as the liquid products. The methods are exemplified utilizing photocatalytic titania particles in an iron-based aqueous electrolyte for effective oxygen evolution and mediator reduction reactions under illumination. Several product characterization methods, including an optical oxygen sensor, pressure sensor, gas chromatography, and UV/Vis spectroscopy are used and compared for accurate, high-resolution gas-products and mediator conversion measurements. Advantages of each technique are discussed. A high Faraday efficiency of 97.5\u00b12\u2009% is calculated and the reaction rate limits are investigated.", "date": "2017-05-22", "date_type": "published", "publication": "ChemSusChem", "volume": "10", "number": "10", "publisher": "Wiley", "pagerange": "2158-2166", "id_number": "CaltechAUTHORS:20170317-084105989", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170317-084105989", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "155876" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201601901", "primary_object": { "basename": "cssc201601901-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/vdgnv-gry63/files/cssc201601901-sup-0001-misc_information.pdf" }, "pub_year": "2017", "author_list": "Han, Lihao; Lin, Meng; et el." }, { "id": "https://authors.library.caltech.edu/records/n5fa1-84d93", "eprint_id": 89638, "eprint_status": "archive", "datestamp": "2023-08-19 03:12:28", "lastmod": "2023-10-18 22:53:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Solar-Driven Reduction of 1 atm CO_2 to Formate at 10% Energy-Conversion Efficiency by Use of a TiO_2-Protected III-V Tandem Photoanode in Conjunction with a Bipolar Membrane and a Pd/C Cathode Electrocatalyst", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 ECS - The Electrochemical Society. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. The authors also thank N. Dalleska (Caltech) for his assistance with measurements and analysis of the ICPMS and TIC data.", "abstract": "A solar-driven CO_2-reduction (CO2R) cell, consisting of a tandem GaAs/InGaP/TiO_2/Ni photoanode in 1.0 M KOH(aq) (pH=13.7) to facilitate the oxygen-evolution reaction (OER), a Pd/C nanoparticle-coated Ti mesh cathode in 2.8 M KHCO_3(aq) (pH=8.0) to perform the CO_2R reaction, and a bipolar membrane to allow for steady-state operation of the catholyte and anolyte at different bulk pH values, was constructed. At the operational current density of 8.5 mA cm^(-2), in 2.8 M KHCO_3(aq), the cathode exhibited <100 mV overpotential and >94% Faradaic efficiency for the reduction of 1 atm of CO_2(g)to formate. The anode exhibited 320 \u00b1 7 mV overpotential for the OER in 1.0 M KOH(aq), and the bipolar membrane exhibited ~480 mV voltage loss with minimal product crossover as well as >90% and >95% selectivity for protons and hydroxide ions, respectively. The solar-driven CO_2R cell converted sunlight to fuels at an energy-conversion efficiency of ~10%.", "date": "2017-05-20", "date_type": "published", "publication": "ECS Transactions", "volume": "77", "number": "4", "publisher": "Electrochemical Society", "pagerange": "31-41", "id_number": "CaltechAUTHORS:20180914-100811320", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100811320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1149/07704.0031ecst", "pub_year": "2017", "author_list": "Zhou, Xinghao; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/5hvcc-yn155", "eprint_id": 89639, "eprint_status": "archive", "datestamp": "2023-08-19 03:12:35", "lastmod": "2023-10-18 22:53:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "K. T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H. J." }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Efficiency Limits for Hydrogen and Formate Production via Fully-Integrated Photoelectrochemical Devices", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 ECS - The Electrochemical Society. \n\nWe are grateful to Dr. C.X. Xiang for useful discussion regarding realistic CO_2 reduction device designs. This material is based, in part, upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "Limiting efficiencies play a critical role in determining the viability of proposed technologies and, consequently, in motivating and guiding device development. Herein we present an analytic, unified framework for fully-integrated photoelectrochemical device performance and apply it to water-splitting and CO_2 reduction reactions for hydrogen and formate production, respectively. An analytic form for the current-voltage relationship of a photoelectrochemical device is used to calculate limiting efficiencies under specific ideal and realistic conditions for single, dual and triple junction photodiode units. Differences in realistic limiting efficiencies for hydrogen and formate production arise not only from disparate catalyst performance but also from design considerations for liquid vs. gas products and realistic operating pH. The results indicate that dual junction devices are sufficient for water-splitting devices, while triple junction devices are more ideal for CO_2 reduction devices with current high performance components.", "date": "2017-05-20", "date_type": "published", "publication": "ECS Transactions", "volume": "77", "number": "4", "publisher": "Electrochemical Society", "pagerange": "15-23", "id_number": "CaltechAUTHORS:20180914-100811455", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100811455", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/07704.0015ecst", "pub_year": "2017", "author_list": "Fountaine, K. T. and Lewerenz, H. J." }, { "id": "https://authors.library.caltech.edu/records/pb23x-7cx50", "eprint_id": 82203, "eprint_status": "archive", "datestamp": "2023-08-19 03:08:38", "lastmod": "2023-10-23 15:09:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Torelli-Daniel-A", "name": { "family": "Torelli", "given": "Daniel" }, "orcid": "0000-0002-6222-817X" }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "Chu F." } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." }, "orcid": "0000-0003-2467-6630" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Reprint of: Surface reconstruction of pure-Cu single-crystal electrodes under CO-reduction potentials in alkaline solutions: A study by seriatim ECSTM-DEMS", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 Elsevier B.V. \n\nReceived 31 July 2016, Revised 17 September 2016, Accepted 20 September 2016, Available online 3 May 2017. \n\nA publisher's error resulted in this article appearing in the wrong issue. The article is reprinted here for the reader's convenience and for the continuity of the special issue. For citation purposes, please use the original publication details; Journal of Electroanalytical Chemistry Volume 780, 1 November 2016, Pages 290\u2013295. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "Quasi-operando electrochemical scanning tunneling microscopy (ECSTM) recently showed that a polycrystalline Cu electrode kept in 0.1 M KOH at \u2212 0.9 V (SHE), a potential very close to that for electrochemical CO reduction, underwent a two-step surface reconstruction, initially to Cu(111), or Cu(pc)-[Cu(111)], and terminally to Cu(100), or Cu(pc)-[Cu(100)]. When subjected to monolayer-limited Cu_((s)) \u2194 Cu2O_((s))oxidation-reduction cycles (ORC), the Cu(pc)-[Cu(100)] surface was further transformed to Cu(pc)-[Cu(511)] that produced C_2H_5OH exclusively, as detected by differential electrochemical mass spectrometry, at an overvoltage lower by 645 mV relative to that for the formation of hydrocarbons. In this paper, results are presented from studies with the native monocrystalline surfaces Cu(111), Cu(100) and Cu(110). Whereas the intermediate Cu(pc)-[Cu(111)] layer was eventually converted to Cu(pc)-[Cu(100)], the surface of a pristine Cu(111) single crystal itself showed no such conversion. The surface of an original Cu(100) electrode likewise proved impervious to potential perturbations. In contrast, the outer plane of a Cu(110) crystal underwent three transformations: first to disordered Cu(110)-d[Cu(110)], then to disordered Cu(110)-d[Cu(111)], and finally to an ordered Cu(110)-[Cu(100)] plane. After multiple ORC, the converted [Cu(100)] lattice atop the Cu(110) crystal did not generate ethanol, in contrast to the [Cu(100)] phase above the Cu(pc) bulk. Quasi-operando ECSTM captured the disparity: Post-ORC, Cu(110)-[Cu(100)] was converted, not to Cu(110)-[Cu(511)], but to an ordered but catalytically inactive Cu(110)-[Cu(111)]; hence, no C_2H_5OH production upon reduction of CO, as would have been the case for a stepped Cu(511) surface.", "date": "2017-05-15", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "793", "publisher": "Elsevier", "pagerange": "113-118", "id_number": "CaltechAUTHORS:20171009-095823966", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20171009-095823966", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2017.04.037", "pub_year": "2017", "author_list": "Kim, Youn-Geun; Javier, Alnald; et el." }, { "id": "https://authors.library.caltech.edu/records/cejcq-j3821", "eprint_id": 75204, "eprint_status": "archive", "datestamp": "2023-08-19 03:01:37", "lastmod": "2023-10-25 14:50:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-M-R", "name": { "family": "Singh", "given": "Meenesh R." }, "orcid": "0000-0002-3638-8866" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Evaluation of flow schemes for near-neutral pH electrolytes in solar-fuel generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Royal Society of Chemistry. \n\nReceived 01 Feb 2017, Accepted 23 Feb 2017. First published online 23 Feb 2017. \n\nThis material is based on the work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award number DE-SC0004993.\n\nSupplemental Material - c7se00062f1.pdf
", "abstract": "The electrochemical performance of three different types of membrane-containing electrolyte-flow schemes for solar-driven water splitting has been studied quantitatively using 1-dimensional and 2-dimensional multi-physics models. The three schemes include a recirculation scheme with a well-mixed bulk electrolyte, a recirculation scheme with laminar flow fields, and a fresh-feed scheme with laminar flow fields. The Nernstian potential loss associated with pH gradients at the electrode surfaces, the resistive loss between the cathode and anode, the product-gas crossovers, and the required pumping energy in all three schemes have been evaluated as a function of the operational current density, the flow rates for the electrolyte, and the physical dimensions of the devices. The trade-offs in the voltage loss, safety considerations, and energy inputs from the balance-of-systems required to produce a practical device have been evaluated and compared to membrane-free devices as well as to devices that operate at extreme pH values.", "date": "2017-05-01", "date_type": "published", "publication": "Sustainable Energy and Fuels", "volume": "1", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "458-466", "id_number": "CaltechAUTHORS:20170317-120009870", "issn": "2398-4902", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170317-120009870", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C7SE00062F", "primary_object": { "basename": "c7se00062f1.pdf", "url": "https://authors.library.caltech.edu/records/cejcq-j3821/files/c7se00062f1.pdf" }, "pub_year": "2017", "author_list": "Singh, Meenesh R.; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/fbxbx-ket38", "eprint_id": 75233, "eprint_status": "archive", "datestamp": "2023-08-19 02:35:45", "lastmod": "2023-10-25 14:52:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ding-Feizhi", "name": { "family": "Ding", "given": "Feizhi" } }, { "id": "Manby-F-R", "name": { "family": "Manby", "given": "Frederick R." }, "orcid": "0000-0001-7611-714X" }, { "id": "Miller-T-F-III", "name": { "family": "Miller", "given": "Thomas F., III" }, "orcid": "0000-0002-1882-5380" } ] }, "title": "Embedded Mean-Field Theory with Block-Orthogonalized Partitioning", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived 1 November 2016. Published online 28 February 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Additionally, T.F.M. acknowledges support from a Camille Dreyfus Teacher-Scholar Award, and F.R.M. acknowledges funding from EPSRC (EP/M013111/1). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ct6b01065_si_001.pdf
", "abstract": "Embedded mean-field theory (EMFT) provides a simple, flexible framework for describing subsystems at different levels of mean-field theory. Subsystems are defined by partitioning a one-particle basis set, with a natural choice being the atomic orbital (AO) basis. Although generally well behaved, EMFT with AO partitioning can exhibit unphysical collapse of the self-consistent solution. To avoid this issue, we introduce subsystem partitioning of a block-orthogonalized (BO) basis set; this eliminates the unphysical collapse without significantly increasing computational cost. We also investigate a non-self-consistent implementation of EMFT, in which the density matrix is obtained using BO partitioning and the final energy evaluated using AO partitioning; this density-corrected EMFT approach is found to yield more accurate energies than BO partitioning while also avoiding issues of the unphysical collapse. Using these refined implementations of EMFT, previously proposed descriptions of the exact-exchange coupling between subsystems are compared: although the EX1 coupling scheme is slightly more accurate than EX0, the small improvement does not merit its substantially greater computational cost.", "date": "2017-04-11", "date_type": "published", "publication": "Journal of Chemical Theory and Computation", "volume": "13", "number": "4", "publisher": "American Chemical Society", "pagerange": "1605-1615", "id_number": "CaltechAUTHORS:20170320-094437871", "issn": "1549-9618", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170320-094437871", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Engineering and Physical Sciences Research Council (EPSRC)", "grant_number": "EP/M013111/1" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jctc.6b01065", "primary_object": { "basename": "ct6b01065_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fbxbx-ket38/files/ct6b01065_si_001.pdf" }, "pub_year": "2017", "author_list": "Ding, Feizhi; Manby, Frederick R.; et el." }, { "id": "https://authors.library.caltech.edu/records/k7z3d-ng196", "eprint_id": 76465, "eprint_status": "archive", "datestamp": "2023-08-19 02:32:46", "lastmod": "2023-10-25 16:01:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yao-Yuan", "name": { "family": "Yao", "given": "Yuan" } }, { "id": "Lee-Kyu-Tae", "name": { "family": "Lee", "given": "Kyu-Tae" } }, { "id": "Sheng-Xing", "name": { "family": "Sheng", "given": "Xing" } }, { "id": "Batara-N-A", "name": { "family": "Batara", "given": "Nicolas A." } }, { "id": "Hong-Nina", "name": { "family": "Hong", "given": "Nina" } }, { "id": "He-Junwen", "name": { "family": "He", "given": "Junwen" } }, { "id": "Xu-Lu", "name": { "family": "Xu", "given": "Lu" }, "orcid": "0000-0002-0021-9876" }, { "id": "Hussain-M-M", "name": { "family": "Hussain", "given": "Muhammad M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Nuzzo-R-G", "name": { "family": "Nuzzo", "given": "Ralph G." }, "orcid": "0000-0003-2310-2045" }, { "id": "Rogers-J-A", "name": { "family": "Rogers", "given": "John A." }, "orcid": "0000-0002-3830-5980" } ] }, "title": "Porous Nanomaterials for Ultrabroadband Omnidirectional Anti-Reflection Surfaces with Applications in High Concentration Photovoltaics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 WILEY-VCH Verlag GmbH & Co. \n\nIssue online: 5 April 2017. Version of record online: 6 December 2016. Manuscript Revised: 14 October 2016. Manuscript Received: 7 September 2016. \n\nY.Y. and K.-T.L. contributed equally to this work. This work was supported by the \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001293. X.S. acknowledges the support from National Natural Science Foundation of China (Project 51602172). M.M.H. acknowledges the support from King Abdullah University of Science and Technology (KAUST) Technology Transfer Office under Award No. GEN-01-4014. The authors thank B. Henderson (Sensofar), K. Walsh (UIUC), and J. C. Mabon (UIUC) for their assistance with materials characterization.\n\nSupplemental Material - aenm201601992-sup-0001-S1.pdf
", "abstract": "Materials for nanoporous coatings that exploit optimized chemistries and self-assembly processes offer capabilities to reach \u224898% transmission efficiency and negligible scattering losses over the broad wavelength range of the solar spectrum from 350 nm to 1.5 \u00b5m, on both flat and curved glass substrates. These nanomaterial anti-reflection coatings also offer wide acceptance angles, up to \u00b140\u00b0, for both s- and p-polarization states of incident light. Carefully controlled bilayer films have allowed for the fabrication of dual-sided, gradient index profiles on plano-convex lens elements. In concentration photovoltaics platforms, the resultant enhancements in the photovoltaics efficiencies are \u22488%, as defined by experimental measurements on systems that use microscale triple-junction solar cells. These materials and their applications in technologies that require control over interface reflections have the potential for broad utility in imaging systems, photolithography, light-emitting diodes, and display technologies.", "date": "2017-04-05", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "7", "number": "7", "publisher": "Wiley", "pagerange": "Art. No. 1601992", "id_number": "CaltechAUTHORS:20170410-080135691", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170410-080135691", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51602172" }, { "agency": "King Abdullah University of Science and Technology (KAUST)", "grant_number": "GEN-01-4014" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201601992", "primary_object": { "basename": "aenm201601992-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/k7z3d-ng196/files/aenm201601992-sup-0001-S1.pdf" }, "pub_year": "2017", "author_list": "Yao, Yuan; Lee, Kyu-Tae; et el." }, { "id": "https://authors.library.caltech.edu/records/wyv6e-59b65", "eprint_id": 77217, "eprint_status": "archive", "datestamp": "2023-08-19 02:24:35", "lastmod": "2023-10-25 21:59:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bouabadi-B", "name": { "family": "Bouabadi", "given": "B." } }, { "id": "Aggour-M", "name": { "family": "Aggour", "given": "M." } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H.-J." }, "orcid": "0000-0001-8433-9471" }, { "id": "Lublow-M", "name": { "family": "Lublow", "given": "M." } } ] }, "title": "Enhanced plasmon-mediated photo-assisted hydrogen evolution on silicon by interfacial modification", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 Springer Science+Business Media Dordrecht. \n\nReceived: 23 November 2016; Accepted: 6 February 2017; Published online: 16 February 2017. \n\nThe joint discussion and interpretation of the data and contributions to the manuscript (H.J.L.) was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993.", "abstract": "The superior catalytic activity of Pt towards proton reduction suggests application of Pt also in device architectures where hydrogen is produced by light-generated charge carriers. Large optical absorption cross sections of Pt nanoparticles, however, turn the attention to potential substitutes for Pt such as Au with more advantageous optical properties. In order to approach a functional Si/Au photocathode for hydrogen evolution, we report here on modifications of the Si\u2013Au interface which result in improvements of charge transfer kinetics and optical properties of the device. After current-less deposition of Au nanoparticles onto silicon, these improvements are realized by chemical oxide exchange reactions at the Si/SiO_2/Au interface, i.e., dynamic etching of SiO_2 and re-oxidation of Si in NH_4F (40%). A chemical reaction route for the reformation of the SiO_2 layer in the presence of Au and the aqueous NH_4F solution is discussed. Simultaneous to the modification of the Si/SiO_2 interface, small Au nanoparticles form larger clusters with enhanced effective scattering cross sections. Thereby, improved electronic interface properties and enhanced forward scattering of light increase the saturation photocurrent density by about 9% from 32 to 35 mA cm^(\u22122). Improved stability of the device in acidic electrolytes, near the thermodynamic potential for evolution of hydrogen, is furthermore discussed.", "date": "2017-04", "date_type": "published", "publication": "Journal of Applied Electrochemistry", "volume": "47", "number": "4", "publisher": "Springer", "pagerange": "457-466", "id_number": "CaltechAUTHORS:20170505-095702134", "issn": "0021-891X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170505-095702134", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s10800-017-1055-4", "pub_year": "2017", "author_list": "Bouabadi, B.; Aggour, M.; et el." }, { "id": "https://authors.library.caltech.edu/records/5jbv8-rzx78", "eprint_id": 75584, "eprint_status": "archive", "datestamp": "2023-08-19 02:16:38", "lastmod": "2023-10-25 15:09:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Moreno-Hernandez-Ivan-A", "name": { "family": "Moreno-Hernandez", "given": "Ivan A." }, "orcid": "0000-0001-6461-9214" }, { "id": "Schmidt-William-C", "name": { "family": "Schmidt", "given": "William C." } }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Crompton-J-Chance", "name": { "family": "Crompton", "given": "J. Chance" } }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A comparison of the chemical, optical and electrocatalytic properties of water-oxidation catalysts for use in integrated solar-fuel generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 Royal Society of Chemistry. \n\nReceived 7th December 2016 , Accepted 9th March 2017. First published on the web 9th March 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This work was also supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. This material is also based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469 (IAM).\n\nSupplemental Material - c6ee03563a1_si.pdf
", "abstract": "The in situ optical properties and electrocatalytic performance of representative catalysts for the oxygen-evolution reaction (OER) have been considered together to evaluate system-level effects that accompany the integration of OER catalysts into a solar-fuel device driven by a tandem-junction light absorber with a photoanode top cell, i.e., a design that requires incident light to be transmitted through the OER catalyst before reaching a semiconducting light absorber. The relationship between the overpotential and optical transmission of the catalysts determined the attainable efficiencies for integrated solar-fuel devices as well as the optimal band gaps for the photoanode in such devices. The systems investigated generally showed: (1) the OER catalysts dissolved in acid, and were less stable in buffered near-neutral pH electrolytes than in strongly alkaline electrolytes; (2) higher overpotentials were required to drive the OER at a specified current density when the catalysts were operated in contact with near-neutral pH electrolytes than strong alkaline electrolytes; (3) for some of the OER catalysts, the electrocatalytic activity and in situ absorption spectra depended strongly on the preparation method; (4) increasing the loading of the electrocatalyst reduced the overpotential and the optical transmission; (5) for the catalysts studied, the optical transmission and overpotential were generally correlated, and the trend lines did not cross, indicating that based on these factors alone, the optimal approach is to use lower loadings of highly active catalysts, rather than to use a less active but more transparent catalysts; (6) for a solar-fuel device driven by semiconductors operating at the Shockley\u2013Queisser limit and using a continuous film of a given OER catalyst in the path of incident light, the efficiency decrease due to the reduced optical transmittance that accompanies increased OER catalyst loading can be substantially greater than any efficiency increase that might be gained through the reduction in catalytic overpotential by increasing the catalyst loading; and (7) HER catalysts possessed the same performance trade-off when the light is incident through the HER catalysts as is observed for OER catalysts when the light is incident from the OER side.", "date": "2017-04", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "10", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "987-1002", "id_number": "CaltechAUTHORS:20170331-105139021", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170331-105139021", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1039/C6EE03563A", "primary_object": { "basename": "c6ee03563a1_si.pdf", "url": "https://authors.library.caltech.edu/records/5jbv8-rzx78/files/c6ee03563a1_si.pdf" }, "pub_year": "2017", "author_list": "Sun, Ke; Moreno-Hernandez, Ivan A.; et el." }, { "id": "https://authors.library.caltech.edu/records/cc8hn-8qy80", "eprint_id": 76482, "eprint_status": "archive", "datestamp": "2023-08-19 02:12:01", "lastmod": "2023-10-25 16:02:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Naserifar-S", "name": { "family": "Naserifar", "given": "Saber" }, "orcid": "0000-0002-1069-9789" }, { "id": "Brooks-D-J", "name": { "family": "Brooks", "given": "Daniel J." } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Cvicek-V", "name": { "family": "Cvicek", "given": "Vaclav" } } ] }, "title": "Polarizable charge equilibration model for predicting accurate electrostatic interactions in molecules and solids", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 AIP Publishing. \n\nPublished Online: March 2017 Accepted: March 2017. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. DOE under Award No. DE-SC0004993. We thank Dr. Qingsong Zhang, Dr. Sergey Zybin, and Dr. Andres Jaramillo-Botero for useful discussions.\n\nPublished - 1.4978891.pdf
", "abstract": "Electrostatic interactions play a critical role in determining the properties, structures, and dynamics of chemical, biochemical, and material systems. These interactions are described well at the level of quantum mechanics (QM) but not so well for the various models used in force field simulations of these systems. We propose and validate a new general methodology, denoted PQEq, to predict rapidly and dynamically the atomic charges and polarization underlying the electrostatic interactions. Here the polarization is described using an atomic sized Gaussian shaped electron density that can polarize away from the core in response to internal and external electric fields, while at the same time adjusting the charge on each core (described as a Gaussian function) so as to achieve a constant chemical potential across all atoms of the system. The parameters for PQEq are derived from experimental atomic properties of all elements up to Nobelium (atomic no. = 102). We validate PQEq by comparing to QM interaction energy as probe dipoles are brought along various directions up to 30 molecules containing H, C, N, O, F, Si, P, S, and Cl atoms. We find that PQEq predicts interaction energies in excellent agreement with QM, much better than other common charge models such as obtained from QM using Mulliken or ESP charges and those from standard force fields (OPLS and AMBER). Since PQEq increases the accuracy of electrostatic interactions and the response to external electric fields, we expect that PQEq will be useful for a large range of applications including ligand docking to proteins, catalytic reactions, electrocatalysis, ferroelectrics, and growth of ceramics and films, where it could be incorporated into standard force fields as OPLS, AMBER, CHARMM, Dreiding, ReaxFF, and UFF.", "date": "2017-03-28", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "146", "number": "12", "publisher": "American Institute of Physics", "pagerange": "Art. No. 124117", "id_number": "CaltechAUTHORS:20170410-141114724", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170410-141114724", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1213", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4978891", "primary_object": { "basename": "1.4978891.pdf", "url": "https://authors.library.caltech.edu/records/cc8hn-8qy80/files/1.4978891.pdf" }, "pub_year": "2017", "author_list": "Naserifar, Saber; Brooks, Daniel J.; et el." }, { "id": "https://authors.library.caltech.edu/records/152x5-mpw71", "eprint_id": 75188, "eprint_status": "archive", "datestamp": "2023-08-19 02:07:23", "lastmod": "2023-10-25 14:49:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Arias-Tomas-A", "name": { "family": "Arias", "given": "Tomas A." }, "orcid": "0000-0001-5880-0260" } ] }, "title": "Grand canonical electronic density-functional theory: Algorithms and applications to electrochemistry", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 AIP Publishing LLC. \n\n(Received 16 January 2017; accepted 27 February 2017; published online 16 March 2017) \n\nR.S. and W.A.G. acknowledge support from the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. R.S. and T.A.A. acknowledge support from the Energy Materials Center at Cornell (EMC^2), an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award No. DE-SC0001086. Calculations in this work used the National Energy Research Scientific Computing Center (NERSC), a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. We thank Kendra Letchworth-Weaver, Kathleen Schwarz, Yuan Ping, Hai Xiao, Tao Cheng, Robert J. Nielsen, and Jason Goodpaster for insightful discussions.\n\nPublished - 1_2E4978411.pdf
Submitted - 1701.04490.pdf
Submitted - 1701.04490v1.pdf
", "abstract": "First-principles calculations combining density-functional theory and continuum solvation models enable realistic theoretical modeling and design of electrochemical systems. When a reaction proceeds in such systems, the number of electrons in the portion of the system treated quantum mechanically changes continuously, with a balancing charge appearing in the continuum electrolyte. A grand-canonical ensemble of electrons at a chemical potential set by the electrode potential is therefore the ideal description of such systems that directly mimics the experimental condition. We present two distinct algorithms: a self-consistent field method and a direct variational free energy minimization method using auxiliary Hamiltonians (GC-AuxH), to solve the Kohn-Sham equations of electronic density-functional theory directly in the grand canonical ensemble at fixed potential. Both methods substantially improve performance compared to a sequence of conventional fixed-number calculations targeting the desired potential, with the GC-AuxH method additionally exhibiting reliable and smooth exponential convergence of the grand free energy. Finally, we apply grand-canonical density-functional theory to the under-potential deposition of copper on platinum from chloride-containing electrolytes and show that chloride desorption, not partial copper monolayer formation, is responsible for the second voltammetric peak.", "date": "2017-03-21", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "146", "number": "11", "publisher": "American Institute of Physics", "pagerange": "Art. No. 114104", "id_number": "CaltechAUTHORS:20170316-155448902", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170316-155448902", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001086" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1254", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4978411", "primary_object": { "basename": "1701.04490.pdf", "url": "https://authors.library.caltech.edu/records/152x5-mpw71/files/1701.04490.pdf" }, "related_objects": [ { "basename": "1701.04490v1.pdf", "url": "https://authors.library.caltech.edu/records/152x5-mpw71/files/1701.04490v1.pdf" }, { "basename": "1_2E4978411.pdf", "url": "https://authors.library.caltech.edu/records/152x5-mpw71/files/1_2E4978411.pdf" } ], "pub_year": "2017", "author_list": "Sundararaman, Ravishankar; Goddard, William A., III; et el." }, { "id": "https://authors.library.caltech.edu/records/4z6m9-0sb31", "eprint_id": 74807, "eprint_status": "archive", "datestamp": "2023-08-22 19:54:22", "lastmod": "2023-10-24 23:18:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Newhouse-Paul-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Chen-Wei", "name": { "family": "Chen", "given": "Wei" } }, { "id": "Li-Guo", "name": { "family": "Li", "given": "Guo" } }, { "id": "Persson-Kristin-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" } ] }, "title": "Solar fuels photoanode materials discovery by integrating high-throughput theory and experiment", "ispublished": "pub", "full_text_status": "public", "keywords": "Solar Fuels Materials; Density-functional Theory; High-throughput Experiments; Complex Oxides; Photocatalysis", "note": "\u00a9 2017 National Academy of Sciences. \n\nApproved February 6, 2017; received for review December 4, 2016; published online before print March 6, 2017. \n\nThe authors thank Anubhav Jain and Joel Haber for helpful discussions. Computational work was supported by the Materials Project Predictive Modeling Center through the US Department of Energy (DOE), Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract DE-AC02\u201305CH11231. Experimental work was performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US DOE (Award DE-SC0004993). Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the US DOE under Contract DE-AC02\u201305CH11231. Computational resources were also provided by the DOE through the National Energy Supercomputing Center, a DOE Office of Science User Facility supported by the Office of Science of the US DOE under Contract DE-AC02-05CH11231.\n\nPublished - PNAS-2017-Yan-3040-3.pdf
Supplemental Material - pnas.1619940114.sapp.pdf
", "abstract": "The limited number of known low-band-gap photoelectrocatalytic materials poses a significant challenge for the generation of chemical fuels from sunlight. Using high-throughput ab initio theory with experiments in an integrated workflow, we find eight ternary vanadate oxide photoanodes in the target band-gap range (1.2\u20132.8 eV). Detailed analysis of these vanadate compounds reveals the key role of VO_4 structural motifs and electronic band-edge character in efficient photoanodes, initiating a genome for such materials and paving the way for a broadly applicable high-throughput-discovery and materials-by-design feedback loop. Considerably expanding the number of known photoelectrocatalysts for water oxidation, our study establishes ternary metal vanadates as a prolific class of photoanode materials for generation of chemical fuels from sunlight and demonstrates our high-throughput theory\u2013experiment pipeline as a prolific approach to materials discovery.", "date": "2017-03-21", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "12", "publisher": "National Academy of Sciences", "pagerange": "3040-3043", "id_number": "CaltechAUTHORS:20170306-150101767", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170306-150101767", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02\u201305CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1619940114", "pmcid": "PMC5373381", "primary_object": { "basename": "PNAS-2017-Yan-3040-3.pdf", "url": "https://authors.library.caltech.edu/records/4z6m9-0sb31/files/PNAS-2017-Yan-3040-3.pdf" }, "related_objects": [ { "basename": "pnas.1619940114.sapp.pdf", "url": "https://authors.library.caltech.edu/records/4z6m9-0sb31/files/pnas.1619940114.sapp.pdf" } ], "pub_year": "2017", "author_list": "Yan, Qimin; Yu, Jie; et el." }, { "id": "https://authors.library.caltech.edu/records/j1j3v-qcr65", "eprint_id": 73865, "eprint_status": "archive", "datestamp": "2023-08-19 01:56:56", "lastmod": "2023-10-24 21:03:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nellist-M-R", "name": { "family": "Nellist", "given": "Michael R." } }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Mark-A", "name": { "family": "Mark", "given": "Andreas" } }, { "id": "G\u00f6drich-S", "name": { "family": "G\u00f6drich", "given": "Sebastian" } }, { "id": "Stelling-C", "name": { "family": "Stelling", "given": "Christian" } }, { "id": "Jiang-Jingjing", "name": { "family": "Jiang", "given": "Jingjing" } }, { "id": "Poddar-R", "name": { "family": "Poddar", "given": "Rakesh" } }, { "id": "Li-Chunzeng", "name": { "family": "Li", "given": "Chunzeng" } }, { "id": "Kumar-R", "name": { "family": "Kumar", "given": "Ravi" } }, { "id": "Papastavrou-G", "name": { "family": "Papastavrou", "given": "Georg" } }, { "id": "Retsch-M", "name": { "family": "Retsch", "given": "Markus" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Boettcher-S-W", "name": { "family": "Boettcher", "given": "Shannon W." }, "orcid": "0000-0001-8971-9123" } ] }, "title": "Atomic force microscopy with nanoelectrode tips for high resolution electrochemical, nanoadhesion and nanoelectrical imaging", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 IOP Publishing Ltd. \n\nReceived 14 November 2016, revised 6 January 2017; Accepted for publication 10 January 2017; Published 31 January 2017. \n\nZH, RP, and CL (employed by Bruker) developed the technique, manufactured the nanoelectrode probe, fabricated the Pt/nitride sample, and were involved in most of the measurements in collaboration with the other authors. Results collected on HOPG and the mesh electrodes were primarily performed by SWB and MRN. SWB, MRN, and ZH led manuscript preparation. SWB and MRN acknowledge support by the Department of Energy, Basic Energy Sciences, award number DE-SC0014279. The modeling and simulation work, and some of the SEM imaging were performed by YC, JJ and CX, and were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. GP, MR, AM, SG and CS performed the preparation of and measurements on the Au nanomesh electrode, and acknowledge the support from the German Research Foundation (DFG) in the framework of the Collaborative Research Center (SFB 840). CS acknowledges support from the Elite Network of Bavaria (ENB). BSB acknowledges support from the National Science Foundation (NSF) Center for Chemical Innovation in Solar Fuels (CHE-1305124) for research (probe testing and device evaluation) carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. RK assisted in the test of chemical compatibility and the PF-TUNA in liquid measurement.", "abstract": "Multimodal nano-imaging in electrochemical environments is important across many areas of science and technology. Here, scanning electrochemical microscopy (SECM) using an atomic force microscope (AFM) platform with a nanoelectrode probe is reported. In combination with PeakForce tapping AFM mode, the simultaneous characterization of surface topography, quantitative nanomechanics, nanoelectronic properties, and electrochemical activity is demonstrated. The nanoelectrode probe is coated with dielectric materials and has an exposed conical Pt tip apex of ~200 nm in height and of ~25 nm in end-tip radius. These characteristic dimensions permit sub-100 nm spatial resolution for electrochemical imaging. With this nanoelectrode probe we have extended AFM-based nanoelectrical measurements to liquid environments. Experimental data and numerical simulations are used to understand the response of the nanoelectrode probe. With PeakForce SECM, we successfully characterized a surface defect on a highly-oriented pyrolytic graphite electrode showing correlated topographical, electrochemical and nanomechanical information at the highest AFM-SECM resolution. The SECM nanoelectrode also enabled the measurement of heterogeneous electrical conductivity of electrode surfaces in liquid. These studies extend the basic understanding of heterogeneity on graphite/graphene surfaces for electrochemical applications.", "date": "2017-03-03", "date_type": "published", "publication": "Nanotechnology", "volume": "28", "number": "9", "publisher": "IOP", "pagerange": "Art. No. 095711", "id_number": "CaltechAUTHORS:20170131-095024118", "issn": "0957-4484", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170131-095024118", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014279" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "SFB 840" }, { "agency": "Elite Network of Bavaria" }, { "agency": "NSF", "grant_number": "CHE-1305124" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1088/1361-6528/aa5839", "pub_year": "2017", "author_list": "Nellist, Michael R.; Chen, Yikai; et el." }, { "id": "https://authors.library.caltech.edu/records/b1w7f-v9x60", "eprint_id": 78308, "eprint_status": "archive", "datestamp": "2023-08-19 01:51:03", "lastmod": "2023-10-25 23:59:40", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Green-M-L", "name": { "family": "Green", "given": "M. L." } }, { "id": "Choi-C-L", "name": { "family": "Choi", "given": "C. L." } }, { "id": "Hattrick-Simpers-J-R", "name": { "family": "Hattrick-Simpers", "given": "J. R." } }, { "id": "Joshi-A-M", "name": { "family": "Joshi", "given": "A. M." } }, { "id": "Takeuchi-Ichiro", "name": { "family": "Takeuchi", "given": "I." } }, { "id": "Barron-S-C", "name": { "family": "Barron", "given": "S. C." } }, { "id": "Campo-E", "name": { "family": "Campo", "given": "E." }, "orcid": "0000-0002-9808-4112" }, { "id": "Chiang-T", "name": { "family": "Chiang", "given": "T." } }, { "id": "Empedocles-S", "name": { "family": "Empedocles", "given": "S." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Kusne-A-G", "name": { "family": "Kusne", "given": "A. G." } }, { "id": "Martin-J", "name": { "family": "Martin", "given": "J." } }, { "id": "Mehta-A", "name": { "family": "Mehta", "given": "A." } }, { "id": "Persson-K", "name": { "family": "Persson", "given": "K." } }, { "id": "Trautt-Z", "name": { "family": "Trautt", "given": "Z." }, "orcid": "0000-0001-5929-0354" }, { "id": "Van-Duren-J", "name": { "family": "Van Duren", "given": "J." } }, { "id": "Zakutayev-A", "name": { "family": "Zakutayev", "given": "A." }, "orcid": "0000-0002-3054-5525" } ] }, "title": "Fulfilling the promise of the materials genome initiative with high-throughput experimental methodologies", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 the Authors. All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived 12 September 2016; accepted 9 February 2017; published online 28 March 2017. \n\nWe are grateful to Alex King, John Newsam, John Perkins, Abhijit V. Shevade, John Smythe, and Ji-Cheng Zhao for manuscript input, and Andrey Dobrynin, Tom Kalil, Om Nalamasu, Nag Patibandla, Shannon Sullivan, and the National Science Foundation (DMR Grant No. 1439054) for their critical role in making the workshop16 possible. J.M.G. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy Award No. DE-SC0004993. A.Z. was supported by U.S. DOE, as a part of a Laboratory Directed Research and Development (LDRD) program, under Contract No. DE-AC36-08GO28308 to NREL.\nCertain commercial equipment, instruments, or materials are identified in this paper to adequately specify the experimental procedure. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.\n\nPublished - 1_2E4977487.pdf
", "abstract": "The Materials Genome Initiative, a national effort to introduce new materials into the market faster and at lower cost, has made significant progress in computational simulation and modeling of materials. To build on this progress, a large amount of experimental data for validating these models, and informing more sophisticated ones, will be required. High-throughput experimentation generates large volumes of experimental data using combinatorial materials synthesis and rapid measurement techniques, making it an ideal experimental complement to bring the Materials Genome Initiative vision to fruition. This paper reviews the state-of-the-art results, opportunities, and challenges in high-throughput experimentation for materials design. A major conclusion is that an effort to deploy a federated network of high-throughput experimental (synthesis and characterization) tools, which are integrated with a modern materials data infrastructure, is needed.", "date": "2017-03", "date_type": "published", "publication": "Applied Physics Reviews", "volume": "4", "number": "1", "publisher": "American Institute of Physics", "pagerange": "Art. No. 011105", "id_number": "CaltechAUTHORS:20170616-160215339", "issn": "1931-9401", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170616-160215339", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1439054" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC36-08GO28308" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4977487", "primary_object": { "basename": "1_2E4977487.pdf", "url": "https://authors.library.caltech.edu/records/b1w7f-v9x60/files/1_2E4977487.pdf" }, "pub_year": "2017", "author_list": "Green, M. L.; Choi, C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/xrgr0-py435", "eprint_id": 72725, "eprint_status": "archive", "datestamp": "2023-08-22 19:46:35", "lastmod": "2023-10-23 22:53:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bukowsky-C-R", "name": { "family": "Bukowsky", "given": "Colton R." }, "orcid": "0000-0003-3577-8050" }, { "id": "Grandidier-J", "name": { "family": "Grandidier", "given": "Jonathan" }, "orcid": "0000-0002-3384-6083" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Callahan-D-M", "name": { "family": "Callahan", "given": "Dennis M." } }, { "id": "Stanbery-B-J", "name": { "family": "Stanbery", "given": "Billy J." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Photon and carrier management design for nonplanar thin-film copper indium gallium selenide photovoltaics", "ispublished": "pub", "full_text_status": "public", "keywords": "Solar cells; Thin film; Light trapping; CIGS; Nanotextured", "note": "\u00a9 2016 Elsevier B.V. \n\nReceived 15 June 2016, Revised 4 November 2016, Accepted 6 November 2016, Available online 3 December 2016. \n\nThe authors thank Hal Emmer, Chris T. Chen, Yulia Tolstova, and Stefan Olmelcheko for helpful discussions. Dr. Stanbery acknowledges the HelioVolt team of co-inventors that developed the processing technology to create these nanotextured absorbers [10]. This work was supported by the U.S. Department of Energy and the Bay Area Photovoltaic Consortium under award number DE-EE0004946 (C.R.B. and D.M.C.) and the Joint Center for Artificial Photosynthesis (KT.F. and H.A.A.), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. K.T. Fountaine was supported by the National Science Foundation Graduate Research Fellowship under Grant No DE-SC0004993.\n\nSupplemental Material - mmc1.pdf
", "abstract": "Nonplanar structured photovoltaic absorber design has potential to achieve high solar cell efficiency with significantly reduced material use. We report optoelectronic simulations that highlight photon and generated carrier management opportunities for improvement of thin film Cu(In_xGa_(1\u2212x))Se_2 (CIGS) device performance. Structures realized via either self-assembly or patterning via nanoimprint lithography, and also a combination of both are predicted to exhibit significant increases in short circuit current density and open circuit voltage simultaneously. The structures investigated include: 1) self-assembled nonplanar structures that strongly scatter incident light and enhance carrier generation near regions of high electric potential, 2) lithographically-patterned embedded periodic dielectric structures, 3) planar dielectric layers that separate the CIGS absorber from the molybdenum back-contact via reduced-area contacts that minimize optical and electronic losses, 4) a combination of these for combined effects. We find that the self-assembled nonplanar CIGS cells with 700 nm planar equivalent thickness, combined with dielectric separation layers yield increases in short circuit current density and open circuit voltage up to 3.4 mA cm\u22122 and 29 mV, respectively. The absolute efficiency increases from 15.4% to 18.1%, compared to the predicted efficiency for planar CIGS thin film cells of equivalent thickness. The addition of a single layer MgF_2 anti-reflection coating brings the maximum predicted efficiency up to 19.7% for randomly textured devices.", "date": "2017-03", "date_type": "published", "publication": "Solar Energy Materials and Solar Cells", "volume": "161", "publisher": "Elsevier", "pagerange": "149-156", "id_number": "CaltechAUTHORS:20161212-115220770", "issn": "0927-0248", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161212-115220770", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0004946" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.solmat.2016.11.008", "primary_object": { "basename": "mmc1.pdf", "url": "https://authors.library.caltech.edu/records/xrgr0-py435/files/mmc1.pdf" }, "pub_year": "2017", "author_list": "Bukowsky, Colton R.; Grandidier, Jonathan; et el." }, { "id": "https://authors.library.caltech.edu/records/4tacc-3wg67", "eprint_id": 74434, "eprint_status": "archive", "datestamp": "2023-08-19 01:40:06", "lastmod": "2023-10-24 22:38:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-Ana-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Schwartzberg-Adam-M", "name": { "family": "Schwartzberg", "given": "Adam M." }, "orcid": "0000-0001-6335-0719" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Experimental and Ab Initio Ultrafast Carrier Dynamics in Plasmonic Nanoparticles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Physical Society. \n\n(Received 11 August 2016; published 21 February 2017) \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors acknowledge support from NG NEXT at Northrop Grumman Corporation. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.\u2009N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.\u2009M.\u2009B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (DE-SC0001293).\n\nPublished - PhysRevLett.118.087401.pdf
Submitted - 1608.03309.pdf
Supplemental Material - SI.pdf
", "abstract": "Ultrafast pump-probe measurements of plasmonic nanostructures probe the nonequilibrium behavior of excited carriers, which involves several competing effects obscured in typical empirical analyses. Here we present pump-probe measurements of plasmonic nanoparticles along with a complete theoretical description based on first-principles calculations of carrier dynamics and optical response, free of any fitting parameters. We account for detailed electronic-structure effects in the density of states, excited carrier distributions, electron-phonon coupling, and dielectric functions that allow us to avoid effective electron temperature approximations. Using this calculation method, we obtain excellent quantitative agreement with spectral and temporal features in transient-absorption measurements. In both our experiments and calculations, we identify the two major contributions of the initial response with distinct signatures: short-lived highly nonthermal excited carriers and longer-lived thermalizing carriers.", "date": "2017-02-24", "date_type": "published", "publication": "Physical Review Letters", "volume": "118", "number": "8", "publisher": "American Physical Society", "pagerange": "Art. No. 087401", "id_number": "CaltechAUTHORS:20170221-134853641", "issn": "0031-9007", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170221-134853641", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1257", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevLett.118.087401", "primary_object": { "basename": "1608.03309.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/1608.03309.pdf" }, "related_objects": [ { "basename": "PhysRevLett.118.087401.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/PhysRevLett.118.087401.pdf" }, { "basename": "SI.pdf", "url": "https://authors.library.caltech.edu/records/4tacc-3wg67/files/SI.pdf" } ], "pub_year": "2017", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/c5v1p-vkv96", "eprint_id": 74130, "eprint_status": "archive", "datestamp": "2023-08-22 19:44:20", "lastmod": "2023-10-24 22:07:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Full atomistic reaction mechanism with kinetics for CO reduction on Cu(100) from ab initio molecular dynamics free-energy calculations at 298 K", "ispublished": "pub", "full_text_status": "public", "keywords": "reaction mechanism; electrocatalysis; copper; QM metadynamics; free-energy reaction barriers", "note": "\u00a9 2017 National Academy of Sciences. \n\nEdited by Richard Eisenberg, University of Rochester, Rochester, NY, and approved January 5, 2017 (received for review July 22, 2016). Published ahead of print February 6, 2017. \n\nThis work was fully supported by the Joint Center for Artificial Photosynthesis, a Department of Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award DE-SC0004993. This work used the Extreme Science and Engineering Discovery Environment and National Energy Research Scientific Computing Center computing resources. \n\nAuthor contributions: T.C. and W.A.G. designed research; T.C. performed research; T.C., H.X., and W.A.G. analyzed data; and T.C., H.X., and W.A.G. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1612106114/-/DCSupplemental.\n\nPublished - PNAS-2017-Cheng-1795-800.pdf
Supplemental Material - pnas.201612106SI.pdf
", "abstract": "A critical step toward the rational design of new catalysts that achieve selective and efficient reduction of CO_2 to specific hydrocarbons and oxygenates is to determine the detailed reaction mechanism including kinetics and product selectivity as a function of pH and applied potential for known systems. To accomplish this, we apply ab initio molecular metadynamics simulations (AIM\u03bcD) for the water/Cu(100) system with five layers of the explicit solvent under a potential of \u22120.59 V [reversible hydrogen electrode (RHE)] at pH 7 and compare with experiment. From these free-energy calculations, we determined the kinetics and pathways for major products (ethylene and methane) and minor products (ethanol, glyoxal, glycolaldehyde, ethylene glycol, acetaldehyde, ethane, and methanol). For an applied potential (U) greater than \u22120.6 V (RHE) ethylene, the major product, is produced via the Eley\u2013Rideal (ER) mechanism using H_2O + e^\u2013. The rate-determining step (RDS) is C\u2013C coupling of two CO, with \u0394G\u2021 = 0.69 eV. For an applied potential less than \u22120.60 V (RHE), the rate of ethylene formation decreases, mainly due to the loss of CO surface sites, which are replaced by H*. The reappearance of C_2H_4 along with CH_4 at U less than \u22120.85 V arises from *CHO formation produced via an ER process of H* with nonadsorbed CO (a unique result). This *CHO is the common intermediate for the formation of both CH_4 and C_2H_4. These results suggest that, to obtain hydrocarbon products selectively and efficiency at pH 7, we need to increase the CO concentration by changing the solvent or alloying the surface.", "date": "2017-02-21", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "114", "number": "8", "publisher": "National Academy of Sciences", "pagerange": "1795-1800", "id_number": "CaltechAUTHORS:20170207-102433252", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170207-102433252", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1251", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1612106114", "pmcid": "PMC5338443", "primary_object": { "basename": "pnas.201612106SI.pdf", "url": "https://authors.library.caltech.edu/records/c5v1p-vkv96/files/pnas.201612106SI.pdf" }, "related_objects": [ { "basename": "PNAS-2017-Cheng-1795-800.pdf", "url": "https://authors.library.caltech.edu/records/c5v1p-vkv96/files/PNAS-2017-Cheng-1795-800.pdf" } ], "pub_year": "2017", "author_list": "Cheng, Tao; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/138zn-mvq86", "eprint_id": 89636, "eprint_status": "archive", "datestamp": "2023-08-19 01:34:01", "lastmod": "2023-10-18 22:53:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "A." }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "J. H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Y.-G." }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "M. P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Electrocatalytic Reduction of CO_2 on Cu and Au/W Electrode Surfaces: Empirical (DEMS) Confirmation of Computational (DFT) Predictions", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 ECS - The Electrochemical Society. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "This work describes the employment of differential electrochemical mass spectrometry (DEMS) as a supplementary experimental approach to theory in the study of the reaction mechanism of the Cu-catalyzed electrochemical reduction of CO_2 by investigating the reduction of reactants and (postulated) intermediates. The empirical inferences: (i) CO is one of the first products of CO_2 reduction, as well as the first intermediate in the formation of more reduced products. (ii) Formaldehyde is not a precursor for C=C bond formation but is an intermediate for the production of methane and ethanol. (iii) Both methane and ethanol can be generated from CO_2 through the protonation of CO and through the HCHO intermediate. (iv) The generation of CH_4 and CH_3CH_2OH from CO and CO_2 has a much higher activation barrier than from HCHO; not unexpected since the formaldehyde intermediate is formed after the (computationally determined) rate-limiting CO-protonation step. In this work, DEMS was also used to test the theoretical prediction suggesting the viability of a bimetallic near-surface alloy (NSA) consisting of Au and W as a CO_2-reduction electrocatalyst selective towards the formation of methanol as a product, as opposed to methane, ethylene or ethanol. At an overlayer NSA that consisted of n monolayers (ML) of Au on a polycrystalline W electrode, W(pc)-n[(1\u00d71)-Au], no methane, methanol, ethylene or ethanol was detected when the coverage of Au was at submonolayer (n = 0.5) or multilayer (n \u2265 2) coverages. However, when the NSA contained only 1 ML of Au, methanol was generated exclusively.", "date": "2017-02-16", "date_type": "published", "publication": "ECS Transactions", "volume": "75", "number": "48", "publisher": "Electrochemical Society", "pagerange": "1-17", "id_number": "CaltechAUTHORS:20180914-100811125", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100811125", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/07548.0001ecst", "pub_year": "2017", "author_list": "Javier, A.; Baricuatro, J. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/e95w4-5v374", "eprint_id": 89637, "eprint_status": "archive", "datestamp": "2023-08-19 01:34:09", "lastmod": "2023-10-18 22:53:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Y.-G." }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "J. H." } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "A." }, "orcid": "0000-0002-0306-5462" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "M. P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Tuning the CO-Reduction Product Distribution by Structural Modification of the Cu Electrode Surface", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2017 ECS - The Electrochemical Society. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "The electrochemical reduction of CO_2 on copper electrodes is known to generate a wide variety of products that include low-molecular-weight hydrocarbons and oxygenates. The product distribution can be regulated to yield a single liquid fuel by the control, at the atomic level, of the structure of the electrode surface. The reaction of interest was the selective CO-to-C_2H_5OH reduction at low potential in alkaline solution. The seriatim or sequential use of electrochemical scanning tunneling microscopy and differential electrochemical mass spectrometry allowed the identification of a particular surface structure responsible for a specific product selectivity. Monolayer-limited Cu \u2194 Cu_2O oxidation-reduction cycles (ORC) in 0.1 M KOH transformed the reconstructed Cu(pc)-[Cu(100)] surface to an ordered stepped surface, Cu(S)-[3(100)\u00d7(111)], or Cu(511) that led to the exclusive production of ethanol. Despite the potential cycles, Cu(111) and (110) surfaces did not produce ethanol. The Cu(111) surface retained its pristine arrangement after a potential hold at -0.9 V and subsequent ORC. Under similar potentiostatic conditions, the Cu(110) surface became Cu(110)-[Cu(100)]; ORC of the reconstructed surface ultimately formed Cu(110)-[Cu(111)].", "date": "2017-02-16", "date_type": "published", "publication": "ECS Transactions", "volume": "75", "number": "50", "publisher": "Electrochemical Society", "pagerange": "87-97", "id_number": "CaltechAUTHORS:20180914-100811230", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100811230", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1149/07550.0087ecst", "pub_year": "2017", "author_list": "Kim, Y.-G.; Baricuatro, J. H.; et el." }, { "id": "https://authors.library.caltech.edu/records/48z17-4dz32", "eprint_id": 73753, "eprint_status": "archive", "datestamp": "2023-08-19 01:28:21", "lastmod": "2023-10-24 16:25:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Omelchenko-S-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Tolstova-Y", "name": { "family": "Tolstova", "given": "Yulia" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Excitonic Effects in Emerging Photovoltaic Materials: A Case Study in Cu_2O", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 American Chemical Society. \n\nReceived: December 19, 2016; Accepted: January 19, 2017; Published: January 19, 2017. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Y.T. and H.A.A. are supported by the Dow Chemical Company under the earth-abundant semiconductor project. S.T.O. thanks S. Yalamanchili, K. Sun, and A. Carim for helpful discussions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz6b00704_si_001.pdf
", "abstract": "Excitonic effects account for a fundamental photoconversion and charge transport mechanism in Cu_2O; hence, the universally adopted \"free carrier\" model substantially underestimates the photovoltaic efficiency for such devices. The quasi-equilibrium branching ratio between excitons and free carriers in Cu_2O indicates that up to 28% of photogenerated carriers during photovoltaic operation are excitons. These large exciton densities were directly observed in photoluminescence and spectral response measurements. The results of a device physics simulation using a model that includes excitonic effects agree well with experimentally measured current\u2013voltage characteristics of Cu_2O-based photovoltaics. In the case of Cu_2O, the free carrier model underestimates the efficiency of a Cu_2O solar cell by as much as 1.9 absolute percent at room temperature.", "date": "2017-02-10", "date_type": "published", "publication": "ACS Energy Letters", "volume": "2", "number": "2", "publisher": "American Chemical Society", "pagerange": "431-437", "id_number": "CaltechAUTHORS:20170126-105722527", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170126-105722527", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Dow Chemical Company" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acsenergylett.6b00704", "primary_object": { "basename": "nz6b00704_si_001.pdf", "url": "https://authors.library.caltech.edu/records/48z17-4dz32/files/nz6b00704_si_001.pdf" }, "pub_year": "2017", "author_list": "Omelchenko, Stefan T.; Tolstova, Yulia; et el." }, { "id": "https://authors.library.caltech.edu/records/dfrpx-yny83", "eprint_id": 73203, "eprint_status": "archive", "datestamp": "2023-08-19 01:23:55", "lastmod": "2023-10-24 15:07:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter S." }, "orcid": "0000-0002-8693-4562" }, { "id": "Marcus-M-A", "name": { "family": "Marcus", "given": "Matthew A." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Yano-J", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" } ] }, "title": "An Operando Investigation of (Ni-Fe-Co-Ce)O_x System as Highly Efficient Electrocatalyst for Oxygen Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "Oxygen evolution reaction (OER), transiton metal oxides, operando techniques, ambient pressure, catalytic conditions, synchrotron radiation, electron spectroscopies", "note": "\u00a9 2016 American Chemical Society. \n\nPublication Date (Web): December 27, 2016. \n\nWe thank Dan Guevarra for his assistance collecting the cyclic voltamograms shown in Figure 1, using the scanning drop electrochemical cell. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The XAS work was done at BL 10.3.2 at the Advanced Light Source, and at BL 7-3 at the Stanford Synchrotron Radiation Lightsource. The AP-XPS work was done at BL 9.3.1 at the Advanced Light Source. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThese two authors equally contributed to the work (M.F. and W.S.D.). \n\nThe authors declare no competing financial interest.\n\nAccepted Version - acscatal_2E6b03126.pdf
Supplemental Material - cs6b03126_si_001.pdf
", "abstract": "The oxygen evolution reaction (OER) is a critical component of industrial processes such as electrowinning of metals and the chlor-alkali process. It also plays a central role in the developing renewable energy field of solar-fuels generation by providing both the protons and electrons needed to generate fuels such as H_2 or reduced hydrocarbons from CO_2. To improve these processes, it is necessary to expand the fundamental understanding of catalytically active species at low overpotential, which will further the development of novel electrocatalysts with high activity and durability. In this context, performing experimental investigations of the electrocatalysts under realistic working regimes, i.e. under operando conditions, is of crucial importance. Here, we study a highly active quinary transition metal oxide-based OER electrocatalyst by means of operando ambient pressure X-ray photoelectron spectroscopy and X-ray absorption spectroscopy performed at the solid/liquid interface. We observe that the catalyst undergoes a clear chemical-structural evolution as a function of the applied potential with Ni, Fe and Co oxy-hydroxides comprising the active catalytic species. While CeO_2 is redox inactive under catalytic conditions, its influence on the redox processes of the transition metals boosts the catalytic activity at low overpotentials, introducing an important design principle for the optimization of electrocatalysts and tailoring of novel materials.", "date": "2017-02-03", "date_type": "published", "publication": "ACS Catalysis", "volume": "7", "number": "2", "publisher": "American Chemical Society", "pagerange": "1248-1258", "id_number": "CaltechAUTHORS:20170104-105146889", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170104-105146889", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1021/acscatal.6b03126", "primary_object": { "basename": "acscatal_2E6b03126.pdf", "url": "https://authors.library.caltech.edu/records/dfrpx-yny83/files/acscatal_2E6b03126.pdf" }, "related_objects": [ { "basename": "cs6b03126_si_001.pdf", "url": "https://authors.library.caltech.edu/records/dfrpx-yny83/files/cs6b03126_si_001.pdf" } ], "pub_year": "2017", "author_list": "Favaro, Marco; Drisdell, Walter S.; et el." }, { "id": "https://authors.library.caltech.edu/records/zb5qx-jf350", "eprint_id": 72001, "eprint_status": "archive", "datestamp": "2023-08-22 19:35:47", "lastmod": "2023-10-23 17:46:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tolstova-Y", "name": { "family": "Tolstova", "given": "Yulia" } }, { "id": "Omelchenko-S-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Blackwell-R-E", "name": { "family": "Blackwell", "given": "Raymond E." } }, { "id": "Shing-Amanda-M", "name": { "family": "Shing", "given": "Amanda M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Polycrystalline Cu_(2)O photovoltaic devices incorporating Zn(O,S) window layers", "ispublished": "pub", "full_text_status": "public", "keywords": "Photovoltaics; Earth-abundant semiconductors; Sputtering; Cuprous oxide; Heterojunction solar cell", "note": "\u00a9 2016 Elsevier. \n\nReceived 21 July 2016; revised 14 October 2016; accepted 29 October 2016; available online 6 November 2016. \n\nThe authors gratefully acknowledge support from the Dow Chemical Company under the earth-abundant semiconductor project. This material is based upon work supported in part by the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect those of NSF or DOE. S.T.O. and A.M.S. acknowledge support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award no. DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. The authors thank Carol Garland at the Caltech Materials Science TEM facility for training and guidance.\n\nSupplemental Material - mmc1.docx
", "abstract": "The tunability of the Zn(O,S) conduction band edge makes it an ideal, earth-abundant heterojunction partner for Cu_(2)O, whose low electron affinity has limited photovoltaic performance with most other heterojunction candidates. However, to date Cu_(2)O/Zn(O,S) solar cells have exhibited photocurrents well below the entitled short-circuit current in the detailed balance limit. In this work, we examine the sources of photocurrent loss in Cu_(2)O/Zn(O,S) solar cells fabricated by sputter deposition of Zn(O,S) on polycrystalline Cu_(2)O substrates grown by thermal oxidation of Cu foils. X-ray photoelectron spectra reveal that Zn(O,S) deposited at room temperature leads to a thin layer of ZnSO_4 at the Zn(O,S)/Cu_(2)O interface that impedes current collection and limits the short circuit current density to 2 mA/cm^2. Deposition of Zn(O,S) at elevated temperatures decreases the presence of interfacial ZnSO_4 and therefore the barrier to photocurrent collection. Optimal photovoltaic performance is achieved at a Zn(O,S) deposition temperature of 100\u00b0C, which enables an increase in the short circuit current density to 5 mA/cm^2, although a small ZnSO_4 layer is still present. Deposition at temperatures above 100\u00b0C leads to a reduction in photovoltaic performance. Spectral response measurements indicate the presence of a barrier to photocurrent and exhibit a strong dependence on voltage and light bias, likely due to the photodoping of Zn(O,S) layer.", "date": "2017-02", "date_type": "published", "publication": "Solar Energy Materials and Solar Cells", "volume": "160", "publisher": "Elsevier", "pagerange": "340-345", "id_number": "CaltechAUTHORS:20161114-145632587", "issn": "0927-0248", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161114-145632587", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow Chemical Company" }, { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.solmat.2016.10.049", "primary_object": { "basename": "mmc1.docx", "url": "https://authors.library.caltech.edu/records/zb5qx-jf350/files/mmc1.docx" }, "pub_year": "2017", "author_list": "Tolstova, Yulia; Omelchenko, Stefan T.; et el." }, { "id": "https://authors.library.caltech.edu/records/ve8t4-0mz05", "eprint_id": 73344, "eprint_status": "archive", "datestamp": "2023-08-19 01:11:40", "lastmod": "2023-10-24 15:14:33", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "An-Qi", "name": { "family": "An", "given": "Qi" }, "orcid": "0000-0003-4838-6232" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Merinov-B-V", "name": { "family": "Merinov", "given": "Boris" }, "orcid": "0000-0002-2783-4262" }, { "id": "Morozov-S-I", "name": { "family": "Morozov", "given": "Sergey I." }, "orcid": "0000-0001-6226-5811" } ] }, "title": "Mechanism and kinetics of the electrocatalytic reaction responsible for the high cost of hydrogen fuel cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2017 the Owner Societies. \n\nReceived 24th November 2016, Accepted 20th December 2016, First published online 21 Dec 2016. \n\nThis work was supported by National Science Foundation (CBET 1512759, program manager Robert McCabe). We thank Dr Ted Yu for helpful discussions. \n\nAuthor contributions: T. C. and W. A. G. proposed the ideas; T. C., Q. A. and S. M. carried out the simulations; T. C. H. X. and B. M. analyzed the results, and the manuscript was written by T. C. and W. A. G. \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - c6cp08055c1_si.pdf
", "abstract": "The sluggish oxygen reduction reaction (ORR) is a major impediment to the economic use of hydrogen fuel cells in transportation. In this work, we report the full ORR reaction mechanism for Pt(111) based on Quantum Mechanics (QM) based Reactive metadynamics (R\u03bcD) simulations including explicit water to obtain free energy reaction barriers at 298 K. The lowest energy pathway for 4 e^\u2212 water formation is: first, *OOH formation; second, *OOH reduction to H_2O and O*; third, O* hydrolysis using surface water to produce two *OH and finally *OH hydration to water. Water formation is the rate-determining step (RDS) for potentials above 0.87 Volt, the normal operating range. Considering the Eley\u2013Rideal (ER) mechanism involving protons from the solvent, we predict the free energy reaction barrier at 298 K for water formation to be 0.25 eV for an external potential below U = 0.87 V and 0.41 eV at U = 1.23 V, in good agreement with experimental values of 0.22 eV and 0.44 eV, respectively. With the mechanism now fully understood, we can use this now validated methodology to examine the changes upon alloying and surface modifications to increase the rate by reducing the barrier for water formation.", "date": "2017-01-28", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "19", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "2666-2673", "id_number": "CaltechAUTHORS:20170109-143914060", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170109-143914060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CBET-1512759" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c6cp08055c", "primary_object": { "basename": "c6cp08055c1_si.pdf", "url": "https://authors.library.caltech.edu/records/ve8t4-0mz05/files/c6cp08055c1_si.pdf" }, "pub_year": "2017", "author_list": "Cheng, Tao; Goddard, William A., III; et el." }, { "id": "https://authors.library.caltech.edu/records/q73hh-sv845", "eprint_id": 72694, "eprint_status": "archive", "datestamp": "2023-08-19 01:04:06", "lastmod": "2023-10-23 22:51:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Atomistic Mechanisms Underlying Selectivities in C_1 and C_2 Products from Electrochemical Reduction of CO on Cu(111)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: July 2, 2016. Publication Date (Web): December 7, 2016. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We are grateful to Dr. Ravishankar Sundararaman, Dr. Robert J. Nielsen, and Prof. Manuel P. Soriaga for helpful discussions. The calculations were carried out on the Zwicky (Caltech) and NERSC computing resources. \n\nThe authors declare no competing financial interest.\n\nPublished - jacs_2E6b06846.pdf
Supplemental Material - ja6b06846_si_001.pdf
", "abstract": "Practical environmental and energy applications of the electrochemical reduction of CO_2 to chemicals and fuels require far more efficient and selective electrocatalysts beyond the only working material Cu, but the wealth of experimental data on Cu can serve to validate any proposed mechanisms. To provide design guidelines, we use quantum mechanics to predict the detailed atomistic mechanisms responsible for C_1 and C_2 products on Cu. Thus, we report the pH dependent routes to the major products, methane and ethylene, and identify the key intermediates where branches to methanol, ketene, ethanol, acetylene and ethane are kinetically blocked. We discovered that surface water on Cu plays a key role in the selectivity for hydrocarbon products over the oxygen-containing alcohol products by serving as a strong proton donor for electrochemical dehydration reductions. We suggest new experiments to validate our predicted mechanisms.", "date": "2017-01-11", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "1", "publisher": "American Chemical Society", "pagerange": "130-136", "id_number": "CaltechAUTHORS:20161209-133639283", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161209-133639283", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b06846", "primary_object": { "basename": "ja6b06846_si_001.pdf", "url": "https://authors.library.caltech.edu/records/q73hh-sv845/files/ja6b06846_si_001.pdf" }, "related_objects": [ { "basename": "jacs_2E6b06846.pdf", "url": "https://authors.library.caltech.edu/records/q73hh-sv845/files/jacs_2E6b06846.pdf" } ], "pub_year": "2017", "author_list": "Xiao, Hai; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/m6ry3-ekr34", "eprint_id": 72768, "eprint_status": "archive", "datestamp": "2023-08-19 01:04:21", "lastmod": "2023-10-23 22:55:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ping-Yuan", "name": { "family": "Ping", "given": "Yuan" } }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" } ] }, "title": "The Reaction Mechanism with Free Energy Barriers at Constant Potentials for the Oxygen Evolution Reaction at the IrO_2 (110) Surface", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: July 21, 2016; Published: December 9, 2016. \n\nWe thank Dr. Ravishankar Sundararaman, Dr. Hai Xiao, Dr. Tao Cheng, and Dr. Yan Choi Lam for useful discussions. This paper is based on work performed in Joint Center for artificial photosynthesis\u2014a DOE innovation hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.\n\nAccepted Version - jacs_2E6b07557.pdf
Supplemental Material - ja6b07557_si_001.pdf
Supplemental Material - ja6b07557_si_002.pdf
", "abstract": "How to efficiently oxidize H_2O to O_2 (Oxygen Evolution Reaction \u2013OER) in photoelectrochemical cells (PEC) is a great challenge due to its complex charge transfer process, high overpotential, and corrosion. So far no OER mechanism has been fully explained atomistically with both thermodynamic and kinetics. IrO_2 is the only known OER catalyst with both high catalytic activity and stability in acidic conditions. This is important because PEC experiments often operate at extreme pH conditions. In this work we performed first principles calculations integrated with implicit solvation at constant potentials to examine the detailed atomistic reaction mechanism of OER at the IrO_2 (110) surface. We determined the surface phase diagram, explored the possible reaction pathways including kinetic barriers, and computed reaction rates based on the micro-kinetic models. This allowed us to resolve several long-standing puzzles about the atomistic OER mechanism.", "date": "2017-01-11", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "139", "number": "1", "publisher": "American Chemical Society", "pagerange": "149-155", "id_number": "CaltechAUTHORS:20161213-102614547", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161213-102614547", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "other_numbering_system": { "items": [ { "id": "1246", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b07557", "primary_object": { "basename": "ja6b07557_si_001.pdf", "url": "https://authors.library.caltech.edu/records/m6ry3-ekr34/files/ja6b07557_si_001.pdf" }, "related_objects": [ { "basename": "ja6b07557_si_002.pdf", "url": "https://authors.library.caltech.edu/records/m6ry3-ekr34/files/ja6b07557_si_002.pdf" }, { "basename": "jacs_2E6b07557.pdf", "url": "https://authors.library.caltech.edu/records/m6ry3-ekr34/files/jacs_2E6b07557.pdf" } ], "pub_year": "2017", "author_list": "Ping, Yuan; Nielsen, Robert J.; et el." }, { "id": "https://authors.library.caltech.edu/records/jbsd5-c0658", "eprint_id": 72553, "eprint_status": "archive", "datestamp": "2023-08-19 01:01:33", "lastmod": "2023-10-23 22:43:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Xue-Yexiang", "name": { "family": "Xue", "given": "Yexiang" } }, { "id": "Bai-Junwen", "name": { "family": "Bai", "given": "Junwen" } }, { "id": "LeBras-R-J", "name": { "family": "LeBras", "given": "Ronan" } }, { "id": "Rappazzo-B-H", "name": { "family": "Rappazzo", "given": "Brendan H." } }, { "id": "Bernstein-R-B", "name": { "family": "Bernstein", "given": "Richard" } }, { "id": "Bjorck-J", "name": { "family": "Bjorck", "given": "Johan" } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "van-Dover-R-B", "name": { "family": "van Dover", "given": "R. Bruce" } }, { "id": "Gomes-C-P", "name": { "family": "Gomes", "given": "Carla P." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Automated Phase Mapping with AgileFD and its Application to Light Absorber Discovery in the V-Mn-Nb Oxide System", "ispublished": "pub", "full_text_status": "public", "keywords": "High-throughput screening, machine learning, x-ray diffraction, combinatorial science, band gap tuning", "note": "\u00a9 2016 American Chemical Society. ACS Editors' Choice. \n\nReceived: October 6, 2016; Revised: November 15, 2016; Published: November 21, 2016. \n\nThe experimental work was performed in the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. The algorithm development is supported by NSF awards CCF-1522054 and CNS-0832782 (Expeditions), CNS-1059284 (Infrastructure), and IIS-1344201 (INSPIRE); and ARO award W911-NF-14-1-0498. Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. The authors thank Apurva Mehta and Douglas G. Van Campen for assistance with collection of synchrotron XRD data.\n\nPublished - acscombsci.6b00153.pdf
Supplemental Material - co6b00153_si_001.zip
", "abstract": "Rapid construction of phase diagrams is a central tenet of combinatorial materials science with accelerated materials discovery efforts often hampered by challenges in interpreting combinatorial x-ray diffraction datasets, which we address by developing AgileFD, an artificial intelligence algorithm that enables rapid phase mapping from a combinatorial library of x-ray diffraction patterns. AgileFD models alloying-based peak shifting through a novel expansion of convolutional nonnegative matrix factorization, which not only improves the identification of constituent phases but also maps their concentration and lattice parameter as a function of composition. By incorporating Gibbs' phase rule into the algorithm, physically meaningful phase maps are obtained with unsupervised operation, and more refined solutions are attained by injecting expert knowledge of the system. The algorithm is demonstrated through investigation of the V-Mn-Nb oxide system where decomposition of eight oxide phases, including two with substantial alloying, provides the first phase map for this pseudo-ternary system. This phase map enables interpretation of high-throughput band gap data, leading to the discovery of new solar light absorbers and the alloying-based tuning of the direct-allowed band-gap energy of MnV2O6. The open-source family of AgileFD algorithms can be implemented into a broad range of high throughput workflows to accelerate materials discovery.", "date": "2017-01-09", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "19", "number": "1", "publisher": "American Chemical Society", "pagerange": "37-46", "id_number": "CaltechAUTHORS:20161205-104618599", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161205-104618599", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CCF-1522054" }, { "agency": "NSF", "grant_number": "CNS-0832782" }, { "agency": "NSF", "grant_number": "CNS-1059284" }, { "agency": "NSF", "grant_number": "IIS-1344201" }, { "agency": "Army Research Office (ARO)", "grant_number": "W911-NF-14-1-0498" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.6b00153", "primary_object": { "basename": "acscombsci.6b00153.pdf", "url": "https://authors.library.caltech.edu/records/jbsd5-c0658/files/acscombsci.6b00153.pdf" }, "related_objects": [ { "basename": "co6b00153_si_001.zip", "url": "https://authors.library.caltech.edu/records/jbsd5-c0658/files/co6b00153_si_001.zip" } ], "pub_year": "2017", "author_list": "Suram, Santosh K.; Xue, Yexiang; et el." }, { "id": "https://authors.library.caltech.edu/records/p87ym-2g985", "eprint_id": 72691, "eprint_status": "archive", "datestamp": "2023-08-19 00:58:57", "lastmod": "2023-10-23 22:51:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Kortlever-R", "name": { "family": "Kortlever", "given": "Ruud" } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Gastight Hydrodynamic Electrochemistry: Design for a Hermetically Sealed Rotating Disk Electrode Cell", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: October 28, 2016; Accepted: December 7, 2016; Published: December 7, 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nAccepted Version - acs_2Eanalchem_2E6b04228.pdf
", "abstract": "Rotating disk electrodes (RDEs) are widely used in electrochemical characterization to analyze the mechanisms of various electrocatalytic reactions. RDE experiments often make use of or require collection and quantification of gaseous products. The combination of rotating parts and gaseous analytes makes the design of RDE cells that allow for headspace analysis challenging due to gas leaks at the interface of the cell body and the rotator. In this manuscript we describe a new, hermetically-sealed electrochemical cell that allows for electrode rotation while simultaneously providing a gastight environment. Electrode rotation in this new cell design is controlled by magnetically coupling the working electrode to a rotating magnetic driver. Calibration of the RDE using a tachometer shows that the rotation speed of the electrode is the same as that of the magnetic driver. To validate the performance of this cell for hydrodynamic measurements, limiting currents from the reduction of a potassium ferrocyanide (K_4[Fe(CN)_6] \u20223H_2O) were measured and shown to compare favorably with calculated values from the Levich equation and with data obtained using more typical, non-gastight RDE cells. Faradaic efficiencies of ~95% were measured in the gas phase for oxygen evolution in alkaline media at an Inconel 625 alloy electrocatalyst during rotation at 1600 rpm. These data verify that a gastight environment is maintained even during rotation.", "date": "2017-01-03", "date_type": "published", "publication": "Analytical Chemistry", "volume": "89", "number": "1", "publisher": "American Chemical Society", "pagerange": "581-585", "id_number": "CaltechAUTHORS:20161209-102641774", "issn": "0003-2700", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161209-102641774", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.analchem.6b04228", "primary_object": { "basename": "acs_2Eanalchem_2E6b04228.pdf", "url": "https://authors.library.caltech.edu/records/p87ym-2g985/files/acs_2Eanalchem_2E6b04228.pdf" }, "pub_year": "2017", "author_list": "Jung, Suho; Kortlever, Ruud; et el." }, { "id": "https://authors.library.caltech.edu/records/6s59h-rjr97", "eprint_id": 98000, "eprint_status": "archive", "datestamp": "2023-08-19 00:55:01", "lastmod": "2023-10-18 16:57:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Seriatim ECSTM-DEMS of Cu-catalyzed reduction of CO in alkaline solution: Operando correlation of electrode-surface atomic structure with product selectivity", "ispublished": "pub", "full_text_status": "restricted", "keywords": "electrochemical scanning tunneling microscopy (ECSTM), Cu-catalyzed electrochemical reduction of CO2, differential electrochemical mass spectrometry (DEMS), seriatim ECSTM-DEMS, Cu(S)-[3(100)x(111)] or Cu(511) stepped surfaces", "note": "\u00a9 2017 Research Trends Ltd. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nNone of the authors have any conflicts of interest to declare.", "abstract": "Copper is the only unalloyed metal that can deliver, in a \"one-pot\" heterogeneous electrochemical reduction of CO_2, a remarkable variety of products, up to fifteen hydrocarbons and oxygenates, in different yields. Its overall activity may be substantial, but its selectivity is far from desirable. In the production of liquid fuels, Cu generates only ethanol at nominal efficiencies that depend upon the particular electrode-surface structure. The optimization of ethanol production may be aided by the correlation, under actual reaction conditions, between the atomic structures of the Cu surfaces and their respective product selectivities. Such operando correlation is made possible by the seriatim (sequential) application of electrochemical scanning tunneling microscopy (ECSTM) and differential electrochemical mass spectrometry (DEMS). The present quasi-review paper describes how seriatim ECSTM-DEMS was utilized to show that ethanol is generated exclusively, sans other hydrocarbons and oxygenates, by a stepped Cu(S)-[3(100)\u00d7(111)], or Cu(511), surface at appreciably low overvoltages.", "date": "2017-01", "date_type": "published", "publication": "Current Topics in Catalysis", "volume": "13", "publisher": "Research Trends Ltd", "pagerange": "1-9", "id_number": "CaltechAUTHORS:20190819-125347135", "issn": "0972-4508", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20190819-125347135", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.31300/ctct.13.2017.1-9", "pub_year": "2017", "author_list": "Kim, Youn-Geun; Javier, Alnald; et el." }, { "id": "https://authors.library.caltech.edu/records/8b3ev-y6d66", "eprint_id": 72196, "eprint_status": "archive", "datestamp": "2023-08-19 00:35:06", "lastmod": "2023-10-23 18:02:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Li-Mufan", "name": { "family": "Li", "given": "Mufan" }, "orcid": "0000-0002-4575-4055" }, { "id": "Zhao-Zipeng", "name": { "family": "Zhao", "given": "Zipeng" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Fortunelli-A", "name": { "family": "Fortunelli", "given": "Alessandro" }, "orcid": "0000-0001-5337-4450" }, { "id": "Chen-Chih-Yen", "name": { "family": "Chen", "given": "Chih-Yen" } }, { "id": "Yu-Rong", "name": { "family": "Yu", "given": "Rong" }, "orcid": "0000-0003-1687-3597" }, { "id": "Zhang-Qinghua", "name": { "family": "Zhang", "given": "Qinghua" } }, { "id": "Gu-Lin", "name": { "family": "Gu", "given": "Lin" } }, { "id": "Merinov-B-V", "name": { "family": "Merinov", "given": "Boris V." }, "orcid": "0000-0002-2783-4262" }, { "id": "Lin-Zhaoyang", "name": { "family": "Lin", "given": "Zhaoyang" }, "orcid": "0000-0002-6474-7184" }, { "id": "Zhu-Enbo", "name": { "family": "Zhu", "given": "Enbo" } }, { "id": "Yu-Ted-H", "name": { "family": "Yu", "given": "Ted" }, "orcid": "0000-0003-3202-0981" }, { "id": "Jia-Qingying", "name": { "family": "Jia", "given": "Qingying" } }, { "id": "Guo-Jinghua", "name": { "family": "Guo", "given": "Jinghua" }, "orcid": "0000-0002-8576-2172" }, { "id": "Zhang-Liang", "name": { "family": "Zhang", "given": "Liang" }, "orcid": "0000-0003-3115-1752" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Huang-Yu", "name": { "family": "Huang", "given": "Yu" }, "orcid": "0000-0003-1793-0741" }, { "id": "Duan-Xiangfeng", "name": { "family": "Duan", "given": "Xiangfeng" }, "orcid": "0000-0002-4321-6288" } ] }, "title": "Ultrafine jagged platinum nanowires enable ultrahigh mass activity for the oxygen reduction reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Association for the Advancement of Science. \n\nReceived 18 April 2016; resubmitted 25 August 2016. Accepted 26 October 2016; Published online 17 November 2016. \n\nSupported by DOE Office of Basic Energy Sciences, Division of Materials Science and Engineering, award DE-SC0008055 (X.D., M.L., and Z.L. for materials synthesis and characterizations); NSF grant CHE-1508692 (Y.H., Z.Z., and E.Z. for electrochemical studies); NSF grant CBET-1512759 (W.A.G., A.F., B.V.M., and T.C. for theoretical computations); and National Natural Science Foundation of China project numbers 51525102, 51390475, and 51371102 (R.Y. for STEM studies). The Advanced Light Source is supported by the Office of Science, Office of Basic Energy Sciences, of DOE under contract DE-AC02-05CH11231. We thank M. A. Marcus for support during the acquisition of XAS data and C. Wu for help with EXAFS data analysis. The aberration-corrected TEM results were achieved (in part) using Titan 80-300 and JEM-ARM 200F. In this work we used the resources of the National Center for Electron Microscopy in Beijing. A patent application on this subject has been filed [UC case no. 2017-108-1-LA (102352-0512)].\n\nSubmitted - Li.SM.pdf
Supplemental Material - Science-JPtNW-Huang-Oct14-wag.pdf
", "abstract": "Improving the platinum (Pt) mass activity for the oxygen reduction reaction (ORR) requires optimization of both the specific activity and the electrochemically active surface area (ECSA). We found that solution-synthesized Pt/NiO core/shell nanowires can be converted into PtNi alloy nanowires through a thermal annealing process and then transformed into jagged Pt nanowires via electrochemical dealloying. The jagged nanowires exhibit an ECSA of 118 square meters per gram of Pt and a specific activity of 11.5 milliamperes per square centimeter for ORR (at 0.9 volts versus reversible hydrogen electrode), yielding a mass activity of 13.6 amperes per milligram of Pt, nearly double previously reported best values. Reactive molecular dynamics simulations suggest that highly stressed, undercoordinated rhombus-rich surface configurations of the jagged nanowires enhance ORR activity versus more relaxed surfaces.", "date": "2016-12-16", "date_type": "published", "publication": "Science", "volume": "354", "number": "6318", "publisher": "American Association for the Advancement of Science", "pagerange": "1414-1419", "id_number": "CaltechAUTHORS:20161121-104400912", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161121-104400912", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0008055" }, { "agency": "NSF", "grant_number": "CHE-1508692" }, { "agency": "NSF", "grant_number": "CBET-1512759" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51525102" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51390475" }, { "agency": "National Natural Science Foundation of China", "grant_number": "51371102" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1126/science.aaf9050", "primary_object": { "basename": "Science-JPtNW-Huang-Oct14-wag.pdf", "url": "https://authors.library.caltech.edu/records/8b3ev-y6d66/files/Science-JPtNW-Huang-Oct14-wag.pdf" }, "related_objects": [ { "basename": "Li.SM.pdf", "url": "https://authors.library.caltech.edu/records/8b3ev-y6d66/files/Li.SM.pdf" } ], "pub_year": "2016", "author_list": "Li, Mufan; Zhao, Zipeng; et el." }, { "id": "https://authors.library.caltech.edu/records/th70g-04474", "eprint_id": 72275, "eprint_status": "archive", "datestamp": "2023-08-19 00:32:42", "lastmod": "2023-10-23 20:34:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Schottky-barrier-free contacts with two-dimensional semiconductors by surface-engineered MXenes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: October 17, 2016; Published: November 22, 2016. \n\nY.L. thanks the support from Resnick Prize Postdoctoral Fellowship at Caltech. This research was funded by DOE DESC0014607. This work used computational resources sponsored by the DOE's Office of Energy Efficiency and Renewable Energy and located at the National Renewable Energy Laboratory; the Extreme Science and Engineering Discovery Environment (XSEDE; supported by NSF Grant ACI-1053575); and the National Energy Research Scientific Computing Center (NERSC; a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231). \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - ja6b10834_si_001.pdf
", "abstract": "Two-dimensional (2D) metal carbides and nitrides, called MXenes, have attracted great interest for applications such as energy storage. Here we demonstrate their potential as Schottky-barrier-free metal contacts to 2D semiconductors, providing a solution to the contact-resistance problem in 2D electronics. Based on first principles calculations, we find that the surface chemistry strongly affects the Fermi level of MXenes: O termination always increases the work function with respect to that of bare surface, OH always decreases it, while F exhibits either trend depending on the specific material. This phenomenon originates from the effect of surface dipoles, which together with the weak Fermi level pinning, enable Schottky-barrier-free hole (or electron) injection into 2D semiconductors through van der Waals junctions with some of the O-terminated (or all the OH-terminated) MXenes. Furthermore, we suggest synthetic routes to control the surface terminations based on the calculated formation energies. This study enhances the understanding of the correlation between surface chemistry and electronic/transport properties of 2D materials, and also gives practical predictions for improving 2D electronics.", "date": "2016-12-14", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "49", "publisher": "American Chemical Society", "pagerange": "15853-15856", "id_number": "CaltechAUTHORS:20161123-091514649", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161123-091514649", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "NSF", "grant_number": "ACI-1053575" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b10834", "primary_object": { "basename": "ja6b10834_si_001.pdf", "url": "https://authors.library.caltech.edu/records/th70g-04474/files/ja6b10834_si_001.pdf" }, "pub_year": "2016", "author_list": "Liu, Yuanyue; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/56jfb-x9n05", "eprint_id": 72846, "eprint_status": "archive", "datestamp": "2023-08-19 00:32:51", "lastmod": "2023-10-23 23:00:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Beatty-J-D", "name": { "family": "Beatty", "given": "John" } }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Cao-Yuan", "name": { "family": "Cao", "given": "Yuan" } }, { "id": "Driver-M-S", "name": { "family": "Driver", "given": "M. Sky" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Kelber-J-A", "name": { "family": "Kelber", "given": "Jeffry A." }, "orcid": "0000-0002-3259-9068" } ] }, "title": "Nucleation of Graphene Layers On Magnetic Oxides: Co_3O_4(111) and Cr_2O_3(0001) from Theory and Experiment", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nPublication Date (Web): December 14, 2016. \n\nWork at UNT was supported by the NSF under grant no. ECCS-1508991, and in part by CSPIN, a funded center of STARnet, a Semiconductor Research Corporation (SRC) program sponsored by MARCO and DARPA under task IDs 2381.001 and 2381.006. The research at Caltech was supported by the NSF (DMR-1436985) and DOE (DE-SC0014607). \n\nThe authors declare no competing financial interests.\n\nSupplemental Material - jz6b02325_si_001.pdf
", "abstract": "We report direct grown strongly adherent graphene on Co_3O_4(111) by Carbon molecular beam epitaxy (MBE) at 850 K and DFT findings that the first graphene layer is reconstructed to fit the Co_3O_4 surface, while subsequent layers retain normal graphene structure. This adherence to the Co_3O_4 structure results from partial bonding of half the carbons to top oxygen of the substrate. This structure is validated by X-ray photoelectron spectroscopy and low energy electron diffraction studies, showing layer-by-layer graphene growth with ~ 0.08 electrons/carbon atom transferred to the oxide from the first graphene layer, in agreement with DFT. In contrast, C MBE on Cr_2O_3(0001) yields only graphite formation at 700 K, with C desorption above 800 K. For Cr_2O_3 DFT finds no strong bonding to the surface, with charge transfer is away from the oxide. Thus strong graphene-to-oxide charge transfer aids nucleation of graphene on incommensurate oxide substrates.", "date": "2016-12-14", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "2017", "number": "8", "publisher": "American Chemical Society", "pagerange": "188-192", "id_number": "CaltechAUTHORS:20161215-105655858", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161215-105655858", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "ECCS-1508991" }, { "agency": "Microelectronics Advanced Research Corporation (MARCO)" }, { "agency": "NSF", "grant_number": "DMR-1436985" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0014607" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "2381.001" }, { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "2381.006" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.6b02325", "primary_object": { "basename": "jz6b02325_si_001.pdf", "url": "https://authors.library.caltech.edu/records/56jfb-x9n05/files/jz6b02325_si_001.pdf" }, "pub_year": "2016", "author_list": "Beatty, John; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/h1vzb-b2w58", "eprint_id": 72718, "eprint_status": "archive", "datestamp": "2023-08-19 00:28:05", "lastmod": "2023-10-23 22:52:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Efficiency limits for photoelectrochemical water-splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Aurhor(s). This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ \n\nReceived: 29 February 2016. Accepted: 21 October 2016. Published online: 02 December 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We are grateful to Dr E. Warmann for useful discussions regarding the impact of external radiative efficiency on photodiode efficiency. \n\nAuthor Contributions: K.T.F. and H.J.L. designed the study and wrote the paper, K.T.F. executed the calculations and analysis, and H.J.L. and H.A.A. advised. All authors reviewed and commented on the manuscript. \n\nData availability: The AM1.5G spectrum data used for the efficiency calculations was derived from the public domain resource, NREL-RREDC: http://rredc.nrel.gov/solar/spectra/am1.5/. Additional data that support the findings of this study, including source code, are available from the corresponding author upon request. \n\nThe authors declare no competing financial interests. \n\nPublisher's note: Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.\n\nPublished - ncomms13706.pdf
Supplemental Material - ncomms13706-s1.pdf
Supplemental Material - ncomms13706-s2.mov
", "abstract": "Theoretical limiting efficiencies have a critical role in determining technological viability and expectations for device prototypes, as evidenced by the photovoltaics community's focus on detailed balance. However, due to their multicomponent nature, photoelectrochemical devices do not have an equivalent analogue to detailed balance, and reported theoretical efficiency limits vary depending on the assumptions made. Here we introduce a unified framework for photoelectrochemical device performance through which all previous limiting efficiencies can be understood and contextualized. Ideal and experimentally realistic limiting efficiencies are presented, and then generalized using five representative parameters\u2014semiconductor absorption fraction, external radiative efficiency, series resistance, shunt resistance and catalytic exchange current density\u2014to account for imperfect light absorption, charge transport and catalysis. Finally, we discuss the origin of deviations between the limits discussed herein and reported water-splitting efficiencies. This analysis provides insight into the primary factors that determine device performance and a powerful handle to improve device efficiency.", "date": "2016-12-02", "date_type": "published", "publication": "Nature Communications", "volume": "7", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 13706", "id_number": "CaltechAUTHORS:20161212-103759501", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161212-103759501", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/ncomms13706", "pmcid": "PMC5146289", "primary_object": { "basename": "ncomms13706-s1.pdf", "url": "https://authors.library.caltech.edu/records/h1vzb-b2w58/files/ncomms13706-s1.pdf" }, "related_objects": [ { "basename": "ncomms13706-s2.mov", "url": "https://authors.library.caltech.edu/records/h1vzb-b2w58/files/ncomms13706-s2.mov" }, { "basename": "ncomms13706.pdf", "url": "https://authors.library.caltech.edu/records/h1vzb-b2w58/files/ncomms13706.pdf" } ], "pub_year": "2016", "author_list": "Fountaine, Katherine T.; Lewerenz, Hans Joachim; et el." }, { "id": "https://authors.library.caltech.edu/records/catv3-xad41", "eprint_id": 69470, "eprint_status": "archive", "datestamp": "2023-08-19 00:12:16", "lastmod": "2023-10-20 19:05:34", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Developing a scalable artificial photosynthesis technology through nanomaterials by design", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 Macmillan Publishers Limited. \n\nReceived 31 July 2015; accepted 1 September 2016; published online 6 December 2016. \n\nThe work described herein was enabled by support from the National Science Foundation Center for Chemical Innovation, the Department of Energy Office of Basic Energy Sciences, the Air Force Office of Scientific Research, the Department of Energy through the Joint Center for Artificial Photosynthesis, and the Gordon and Betty Moore Foundation, as acknowledged in the individual publications referenced herein, as well as for partial salary support for N.S.L. that enabled the preparation of this manuscript. M. McDowell and K. Papadantonakis are acknowledged for assistance in preparation of this manuscript. A special acknowledgment is extended to the enthusiastic, talented and dedicated cohort of graduate students, post-doctoral fellows, collaborators and colleagues for their extraordinary, enabling contributions to this research effort, as acknowledged in the publications described and referenced herein. \n\nThe author declares no competing financial interests.", "abstract": "An artificial photosynthetic system that directly produces fuels from sunlight could provide an approach to scalable energy storage and a technology for the carbon-neutral production of high-energy-density transportation fuels. A variety of designs are currently being explored to create a viable artificial photosynthetic system, and the most technologically advanced systems are based on semiconducting photoelectrodes. Here, I discuss the development of an approach that is based on an architecture, first conceived around a decade ago, that combines arrays of semiconducting microwires with flexible polymeric membranes. I highlight the key steps that have been taken towards delivering a fully functional solar fuels generator, which have exploited advances in nanotechnology at all hierarchical levels of device construction, and include the discovery of earth-abundant electrocatalysts for fuel formation and materials for the stabilization of light absorbers. Finally, I consider the remaining scientific and engineering challenges facing the fulfilment of an artificial photosynthetic system that is simultaneously safe, robust, efficient and scalable.", "date": "2016-12", "date_type": "published", "publication": "Nature Nanotechnology", "volume": "11", "number": "12", "publisher": "Nature Publishing Group", "pagerange": "1010-1019", "id_number": "CaltechAUTHORS:20160805-102228624", "issn": "1748-3387", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160805-102228624", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Air Force Office of Scientific Research (AFOSR)" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1038/nnano.2016.194", "pub_year": "2016", "author_list": "Lewis, Nathan S." }, { "id": "https://authors.library.caltech.edu/records/7sf03-5sk77", "eprint_id": 72314, "eprint_status": "archive", "datestamp": "2023-08-19 00:03:51", "lastmod": "2023-10-23 21:37:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Jin-Jian", "name": { "family": "Zhou", "given": "Jin-Jian" }, "orcid": "0000-0002-1182-9186" }, { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" } ] }, "title": "Ab initio electron mobility and polar phonon scattering in GaAs", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Physical Society. \n\n(Received 10 August 2016; revised manuscript received 18 October 2016; published 28 November 2016) \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nPublished - PhysRevB.94.201201.pdf
Submitted - 1608.03514.pdf
Supplemental Material - supplemental_materials.pdf
", "abstract": "In polar semiconductors and oxides, the long-range nature of the electron-phonon (e\u2212ph) interaction is a bottleneck to compute charge transport from first principles. Here, we develop an efficient ab initio scheme to compute and converge the e\u2212ph relaxation times (RTs) and electron mobility in polar materials. We apply our approach to GaAs, where by using the Boltzmann equation with state-dependent RTs, we compute mobilities in excellent agreement with experiment at 250\u2013500K. The e\u2212ph RTs and the phonon contributions to intravalley and intervalley e\u2212ph scattering are also analyzed. Our work enables efficient ab initio computations of transport and carrier dynamics in polar materials.", "date": "2016-11-15", "date_type": "published", "publication": "Physical Review B", "volume": "94", "number": "20", "publisher": "American Physical Society", "pagerange": "Art. No. 201201(R)", "id_number": "CaltechAUTHORS:20161128-120519486", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161128-120519486", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1103/PhysRevB.94.201201", "primary_object": { "basename": "1608.03514.pdf", "url": "https://authors.library.caltech.edu/records/7sf03-5sk77/files/1608.03514.pdf" }, "related_objects": [ { "basename": "PhysRevB.94.201201.pdf", "url": "https://authors.library.caltech.edu/records/7sf03-5sk77/files/PhysRevB.94.201201.pdf" }, { "basename": "supplemental_materials.pdf", "url": "https://authors.library.caltech.edu/records/7sf03-5sk77/files/supplemental_materials.pdf" } ], "pub_year": "2016", "author_list": "Zhou, Jin-Jian and Bernardi, Marco" }, { "id": "https://authors.library.caltech.edu/records/s704z-73313", "eprint_id": 71343, "eprint_status": "archive", "datestamp": "2023-08-22 19:05:54", "lastmod": "2023-10-23 15:39:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High Throughput Light Absorber Discovery, Part 1: An Algorithm for Automated Tauc Analysis", "ispublished": "pub", "full_text_status": "public", "keywords": "band gap; combinatorial science; high-throughput screening; optical spectroscopy; solar fuels; UV\u2212vis spectroscopy", "note": "\u00a9 2016 American Chemical Society. ACS Editors' Choice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nPublication Date (Web): September 23, 2016. \n\nThis work is performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The authors thank Earl Cornell and Slobodan Mitrovic for assistance with instrument hardware and initial efforts in data processing, Thomas F. Jaramillo for providing insight into the rigors of band gap estimation using Tauc plots, Meyer Pesenson for helpful discussions with data processing, and Lan Zhou for assistance with sample preparation. \n\nThe authors declare no competing financial interest.\n\nPublished - acscombsci.6b00053.pdf
Supplemental Material - co6b00053_si_001.pdf
Supplemental Material - co6b00053_si_002.zip
", "abstract": "High-throughput experimentation provides efficient mapping of composition\u2013property relationships, and its implementation for the discovery of optical materials enables advancements in solar energy and other technologies. In a high throughput pipeline, automated data processing algorithms are often required to match experimental throughput, and we present an automated Tauc analysis algorithm for estimating band gap energies from optical spectroscopy data. The algorithm mimics the judgment of an expert scientist, which is demonstrated through its application to a variety of high throughput spectroscopy data, including the identification of indirect or direct band gaps in Fe_2O_3, Cu_2V_2O_7, and BiVO_4. The applicability of the algorithm to estimate a range of band gap energies for various materials is demonstrated by a comparison of direct-allowed band gaps estimated by expert scientists and by automated algorithm for 60 optical spectra.", "date": "2016-11-14", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "18", "number": "11", "publisher": "American Chemical Society", "pagerange": "673-681", "id_number": "CaltechAUTHORS:20161021-113119506", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161021-113119506", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.6b00053", "primary_object": { "basename": "co6b00053_si_001.pdf", "url": "https://authors.library.caltech.edu/records/s704z-73313/files/co6b00053_si_001.pdf" }, "related_objects": [ { "basename": "co6b00053_si_002.zip", "url": "https://authors.library.caltech.edu/records/s704z-73313/files/co6b00053_si_002.zip" }, { "basename": "acscombsci.6b00053.pdf", "url": "https://authors.library.caltech.edu/records/s704z-73313/files/acscombsci.6b00053.pdf" } ], "pub_year": "2016", "author_list": "Suram, Santosh K.; Newhouse, Paul F.; et el." }, { "id": "https://authors.library.caltech.edu/records/mfnng-68q16", "eprint_id": 71353, "eprint_status": "archive", "datestamp": "2023-08-22 19:06:06", "lastmod": "2023-10-23 15:40:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Van-Campen-D-G", "name": { "family": "Van Campen", "given": "Douglas G." } }, { "id": "Mehta-A", "name": { "family": "Mehta", "given": "Apurva" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High Throughput Light Absorber Discovery, Part 2: Establishing Structure\u2013Band Gap Energy Relationships", "ispublished": "pub", "full_text_status": "public", "keywords": "band gap; combinatorial science; high-throughput screening; optical spectroscopy; solar fuels; UV\u2212vis spectroscopy", "note": "\u00a9 2016 American Chemical Society. ACS Editors' Choice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: April 9, 2016; Revised: September 8, 2016; Publication Date (Web): September 23, 2016. \n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Use of the Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. The authors thank Ryan Jones, Chad Miller, Samuil Belopolskiy, and Tim Dunn for assistance with the synchrotron experiments. \n\nThe authors declare no competing financial interest.\n\nPublished - acscombsci.6b00054.pdf
Supplemental Material - co6b00054_si_001.pdf
Supplemental Material - co6b00054_si_002.zip
", "abstract": "Combinatorial materials science strategies have accelerated materials development in a variety of fields, and we extend these strategies to enable structure\u2013property mapping for light absorber materials, particularly in high order composition spaces. High throughput optical spectroscopy and synchrotron X-ray diffraction are combined to identify the optical properties of Bi\u2013V\u2013Fe oxides, leading to the identification of Bi_4V_(1.5)Fe_(0.5)O_(10.5) as a light absorber with direct band gap near 2.7 eV. The strategic combination of experimental and data analysis techniques includes automated Tauc analysis to estimate band gap energies from the high throughput spectroscopy data, providing an automated platform for identifying new optical materials.", "date": "2016-11-14", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "18", "number": "11", "publisher": "American Chemical Society", "pagerange": "682-688", "id_number": "CaltechAUTHORS:20161021-140906751", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161021-140906751", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acscombsci.6b00054", "primary_object": { "basename": "acscombsci.6b00054.pdf", "url": "https://authors.library.caltech.edu/records/mfnng-68q16/files/acscombsci.6b00054.pdf" }, "related_objects": [ { "basename": "co6b00054_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mfnng-68q16/files/co6b00054_si_001.pdf" }, { "basename": "co6b00054_si_002.zip", "url": "https://authors.library.caltech.edu/records/mfnng-68q16/files/co6b00054_si_002.zip" } ], "pub_year": "2016", "author_list": "Suram, Santosh K.; Newhouse, Paul F.; et el." }, { "id": "https://authors.library.caltech.edu/records/p2ke1-fmg24", "eprint_id": 71886, "eprint_status": "archive", "datestamp": "2023-08-18 23:56:18", "lastmod": "2023-10-23 17:18:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kisielowski-Christian", "name": { "family": "Kisielowski", "given": "C." }, "orcid": "0000-0001-6425-0779" }, { "id": "Frei-H", "name": { "family": "Frei", "given": "H." } }, { "id": "Specht-P", "name": { "family": "Specht", "given": "P." } }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "I. D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Helveg-S", "name": { "family": "Helveg", "given": "S." } } ] }, "title": "Detecting structural variances of Co\u2083O\u2084 catalysts by controlling beam-induced sample alterations in the vacuum of a transmission electron microscope", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Author(s). This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. \n\nReceived: 25 June 2016. Accepted: 19 October 2016. Published: 2 November 2016. \n\nAuthors' contributions: CK recorded and reconstructed the images and drafted the manuscript. PS and SH contributed to the image interpretations. HF, JH and IS provided the differently grown Co_3O_4 material. All authors commented on the manuscript. All authors read and approved the final manuscript. \n\nElectron microscopy is supported by the Molecular Foundry, which is supported by the Office of Science, the Office of Basic Energy Sciences, the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The samples were provided by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC000499. In situ annealing experiments were kindly supported by Haldor Topsoe A/S, Denmark. The authors acknowledge Dr. Jinhui Yang for performing plasma-enhanced ALD. \n\nThe authors declare that they have no competing interests.\n\nPublished - art_3A10.1186_2Fs40679-016-0027-9.pdf
", "abstract": "This article summarizes core aspects of beam-sample interactions in research that aims at exploiting the ability to detect single atoms at atomic resolution by mid-voltage transmission electron microscopy. Investigating the atomic structure of catalytic Co\u2083O\u2084 nanocrystals underscores how indispensable it is to rigorously control electron dose rates and total doses to understand native material properties on this scale. We apply in-line holography with variable dose rates to achieve this goal. Genuine object structures can be maintained if dose rates below ~100 e/\u00c5\u00b2 s are used and the contrast required for detection of single atoms is generated by capturing large image series. Threshold doses for the detection of single atoms are estimated. An increase of electron dose rates and total doses to common values for high resolution imaging of solids stimulates object excitations that restructure surfaces, interfaces, and defects and cause grain reorientation or growth. We observe a variety of previously unknown atom configurations in surface proximity of the Co\u2083O\u2084 spinel structure. These are hidden behind broadened diffraction patterns in reciprocal space but become visible in real space by solving the phase problem. An exposure of the Co\u2083O\u2084 spinel structure to water vapor or other gases induces drastic structure alterations that can be captured in this manner.", "date": "2016-11-02", "date_type": "published", "publication": "Advanced Structural and Chemical Imaging", "volume": "2", "publisher": "Springer", "pagerange": "Art. No. 13", "id_number": "CaltechAUTHORS:20161109-115755580", "issn": "2198-0926", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161109-115755580", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC000499" }, { "agency": "Haldor Topsoe A/S Denmark" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1186/s40679-016-0027-9", "pmcid": "PMC5093192", "primary_object": { "basename": "art_3A10.1186_2Fs40679-016-0027-9.pdf", "url": "https://authors.library.caltech.edu/records/p2ke1-fmg24/files/art_3A10.1186_2Fs40679-016-0027-9.pdf" }, "pub_year": "2016", "author_list": "Kisielowski, C.; Frei, H.; et el." }, { "id": "https://authors.library.caltech.edu/records/weyts-2my13", "eprint_id": 70973, "eprint_status": "archive", "datestamp": "2023-08-22 19:02:35", "lastmod": "2023-10-23 15:14:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Torelli-Daniel-A", "name": { "family": "Torelli", "given": "Daniel" }, "orcid": "0000-0002-6222-817X" }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "Chu F." } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." }, "orcid": "0000-0003-2467-6630" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Surface reconstruction of pure-Cu single-crystal electrodes under Co-reduction potentials in alkaline solutions: A study by seriatim ECSTM-DEMS", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Surface reconstruction of Cu electrodes under CO-reduction potentials; Quasi-operando electrochemical scanning tunneling microscopy; Differential electrochemical mass spectrometry; Seriatim ECSTM-DEMS", "note": "\u00a9 2016 Elsevier. \n\nReceived 31 July 2016; revised 17 September 2016; accepted 20 September 2016; available online 21 September 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.\n\nA publisher's error resulted in this article appearing in the wrong issue. The article is reprinted here for the reader's convenience and for the continuity of the special issue. For citation purposes, please use the original publication details; Journal of Electroanalytical Chemistry Volume 780, 1 November 2016, Pages 290\u2013295", "abstract": "Quasi-operando electrochemical scanning tunneling microscopy (ECSTM) recently showed that a polycrystalline Cu electrode kept in 0.1 M KOH at \u2212 0.9 V (SHE), a potential very close to that for electrochemical CO reduction, underwent a two-step surface reconstruction, initially to Cu(111), or Cu(pc)-[Cu(111)], and terminally to Cu(100), or Cu(pc)-[Cu(100)]. When subjected to monolayer-limited Cu_((s)) \u2194 Cu_2O_((s)) oxidation-reduction cycles (ORC), the Cu(pc)-[Cu(100)] surface was further transformed to Cu(pc)-[Cu(511)] that produced C_2H_5OH exclusively, as detected by differential electrochemical mass spectrometry, at an overvoltage lower by 645 mV relative to that for the formation of hydrocarbons. In this paper, results are presented from studies with the native monocrystalline surfaces Cu(111), Cu(100) and Cu(110). Whereas the intermediate Cu(pc)-[Cu(111)] layer was eventually converted to Cu(pc)-[Cu(100)], the surface of a pristine Cu(111) single crystal itself showed no such conversion. The surface of an original Cu(100) electrode likewise proved impervious to potential perturbations. In contrast, the outer plane of a Cu(110) crystal underwent three transformations: first to disordered Cu(110)-d[Cu(110)], then to disordered Cu(110)-d[Cu(111)], and finally to an ordered Cu(110)-[Cu(100)] plane. After multiple ORC, the converted [Cu(100)] lattice atop the Cu(110) crystal did not generate ethanol, in contrast to the [Cu(100)] phase above the Cu(pc) bulk. Quasi-operando ECSTM captured the disparity: Post-ORC, Cu(110)-[Cu(100)] was converted, not to Cu(110)-[Cu(511)], but to an ordered but catalytically inactive Cu(110)-[Cu(111)]; hence, no C2H5OH production upon reduction of CO, as would have been the case for a stepped Cu(511) surface.", "date": "2016-11-01", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "780", "publisher": "Elsevier", "pagerange": "290-295", "id_number": "CaltechAUTHORS:20161010-151601789", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161010-151601789", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2016.09.029", "pub_year": "2016", "author_list": "Kim, Youn-Geun; Javier, Alnald; et el." }, { "id": "https://authors.library.caltech.edu/records/6x7pr-a3r73", "eprint_id": 73515, "eprint_status": "archive", "datestamp": "2023-08-22 19:00:58", "lastmod": "2023-10-24 15:25:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hsiow-Chuen-Yo", "name": { "family": "Hsiow", "given": "Chuen-Yo" } }, { "id": "Wang-Han-Ying", "name": { "family": "Wang", "given": "Han-Ying" } }, { "id": "Lin-Yu-Hsiang", "name": { "family": "Lin", "given": "Yu-Hsiang" } }, { "id": "Raja-Rathinam", "name": { "family": "Raja", "given": "Rathinam" } }, { "id": "Rwei-Syang-Peng", "name": { "family": "Rwei", "given": "Syang-Peng" } }, { "id": "Chiu-Wen-Yen", "name": { "family": "Chiu", "given": "Wen-Yen" } }, { "id": "Dai-Chi-An", "name": { "family": "Dai", "given": "Chi-An" } }, { "id": "Wang-Leeyih", "name": { "family": "Wang", "given": "Leeyih" } } ] }, "title": "Synthesis and Characterization of Two-Dimensional Conjugated Polymers Incorporating Electron-Deficient Moieties for Application in Organic Photovoltaics", "ispublished": "pub", "full_text_status": "public", "keywords": "two-dimensional conjugated polymer; polymer solar cell; benzo[1,2-b:4,5-b\u2032]dithiophene; thieno[3,4-c]pyrrole-4,6-dione; pyrrolo[3,4-c]pyrrole-1,4-dione; conjugated side chain", "note": "\u00a9 2016 by the authors; licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC-BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nAcademic Editor: Seth B. Darling \n\nReceived: 30 September 2016. Accepted: 22 October 2016. Published: 27 October 2016. \n\nThis research was financially supported by National Taiwan University, Academia Sinica (AS-103-SS-A02), and the Ministry of Science and Technology of the Republic of China (MOST 102-2113-M-002-003-MY3; MOST 105-3113-E-102-010; MOST 104-2911-I-002-574; MOST 105-2119-M-002-030-MY3). \n\nThe authors thank the instrumentation center sponsored by Ministry of Science and Technology and National Taiwan University for NMR and elemental analysis experiments. \n\nAuthor Contributions: Chuen-Yo Hsiow, Han-Ying Wang, Yu-Hsiang Lin, and Rathinam Raja performed the experimental work; Chuen-Yo Hsiow is also responsible for analyzing the experimental data and writing the paper. Syang-Peng Rwei,Wen-Yen Chiu, and Chi-An Dai directed this research; Leeyih Wang directed and supervised the research. \n\nThe authors declare no conflict of interest.\n\nPublished - polymers-08-00382.pdf
Supplemental Material - polymers-08-00382-s001.pdf
", "abstract": "A series of novel p-type conjugated copolymers, PTTVBDT, PTTVBDT-TPD, and PTTVBDT-DPP, cooperating benzo[1,2-b:4,5-b\u2032]dithiophene (BDT) and terthiophene-vinylene (TTV) units with/without thieno[3,4-c]pyrrole-4,6-dione (TPD) or pyrrolo[3,4-c]pyrrole-1,4-dione (DPP) via Stille polymerization were synthesized and characterized. Copolymer PTTVBDT shows a low-lying HOMO energy level and ordered molecular-packing behavior. Furthermore, two terpolymers, PTTVBDT-TPD and PTTVBDT-DPP, display stronger absorption ability, alower-lying HOMO energy level, and preferred molecular orientation, due to the replacement TTV-monomer units with electron-deficient groups. Furthermore, bulk-heterojunction organic solar cells were fabricated using blends of the PTTVBDT-TPD, and PC_(61)BM gave the best power conversion efficiency of 5.01% under the illumination of AM 1.5G, 100 mW\u00b7cm^(\u22122); the short circuit current (J_(sc)) was 11.65 mA\u00b7cm^(\u22122) which displayed a 43.8% improvement in comparison with the PTTVBDT/PC_(61)BM device. These results demonstrate a valid strategy combining the two-dimensional molecular structure with random copolymerization strikes promising conjugated polymers to achieve highly efficient organic photovoltaics.", "date": "2016-11", "date_type": "published", "publication": "Polymers", "volume": "8", "number": "11", "publisher": "MDPI", "pagerange": "Art. No. 382", "id_number": "CaltechAUTHORS:20170117-084349941", "issn": "2073-4360", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170117-084349941", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Academia Sinica", "grant_number": "AS-103-SS-A02" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 102-2113-M-002-003-MY3" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 105-3113-E-102-010" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 104-2911-I-002-574" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "MOST 105-2119-M-002-030-MY3" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.3390/polym8110382", "pmcid": "PMC6432402", "primary_object": { "basename": "polymers-08-00382-s001.pdf", "url": "https://authors.library.caltech.edu/records/6x7pr-a3r73/files/polymers-08-00382-s001.pdf" }, "related_objects": [ { "basename": "polymers-08-00382.pdf", "url": "https://authors.library.caltech.edu/records/6x7pr-a3r73/files/polymers-08-00382.pdf" } ], "pub_year": "2016", "author_list": "Hsiow, Chuen-Yo; Wang, Han-Ying; et el." }, { "id": "https://authors.library.caltech.edu/records/809mh-84v86", "eprint_id": 71337, "eprint_status": "archive", "datestamp": "2023-08-20 14:16:31", "lastmod": "2023-10-23 15:39:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Reaction Mechanisms for the Electrochemical Reduction of CO_2 to CO and Formate on the Cu(100) Surface at 298 K from Quantum Mechanics Free Energy Calculations with Explicit Water", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: August 17, 2016. Publication Date (Web): October 11, 2016. \n\nThis work was fully supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We thank Mr. Yufeng Huang, Dr. Ravishankar Sundararaman, Dr. Robert J. Nielsen, and Prof. Manuel P. Soriaga for helpful discussions. The calculations were carried out mostly on the Zwicky (Caltech) astrophysics computing system [using funding from NSF (CBET 1512759)], with some on NERSC. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja6b08534_si_001.pdf
", "abstract": "Copper is the only elemental metal that reduces a significant fraction of CO_2 to hydrocarbons and alcohols, but the atomistic reaction mechanism that controls the product distributions is not known because it has not been possible to detect the reaction intermediates on the electrode surface experimentally, or to carry out Quantum Mechanics (QM) calculations with a realistic description of the electrolyte (water). Here, we carry out QM calculations with an explicit description of water on the Cu(100) surface (experimentally shown to be stable under CO_2 reduction reaction conditions) to examine the initial reaction pathways to form CO and formate (HCOO\u2013) from CO_2 through free energy calculations at 298 K and pH 7. We find that CO formation proceeds from physisorbed CO_2 to chemisorbed CO_2 (*CO_2^(\u03b4\u2212)), with a free energy barrier of \u0394G\u29e7 = 0.43 eV, the rate-determining step (RDS). The subsequent barriers of protonating *CO_2^(\u03b4\u2212) to form COOH* and then dissociating COOH* to form *CO are 0.37 and 0.30 eV, respectively. HCOO\u2013 formation proceeds through a very different pathway in which physisorbed CO_2 reacts directly with a surface H* (along with electron transfer), leading to \u0394G\u29e7 = 0.80 eV. Thus, the competition between CO formation and HCOO\u2013 formation occurs in the first electron-transfer step. On Cu(100), the RDS for CO formation is lower, making CO the predominant product. Thus, to alter the product distribution, we need to control this first step of CO_2 binding, which might involve controlling pH, alloying, or changing the structure at the nanoscale.", "date": "2016-10-26", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "42", "publisher": "American Chemical Society", "pagerange": "13802-13805", "id_number": "CaltechAUTHORS:20161021-102228722", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161021-102228722", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-1512759" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b08534", "primary_object": { "basename": "ja6b08534_si_001.pdf", "url": "https://authors.library.caltech.edu/records/809mh-84v86/files/ja6b08534_si_001.pdf" }, "pub_year": "2016", "author_list": "Cheng, Tao; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/pfpbe-hez09", "eprint_id": 71357, "eprint_status": "archive", "datestamp": "2023-08-22 18:55:16", "lastmod": "2023-10-23 15:40:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fountaine-Katherine-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Cheng-Wen-Hui", "name": { "family": "Cheng", "given": "Wen-Hui" }, "orcid": "0000-0003-3233-4606" }, { "id": "Bukowsky-Colton-R", "name": { "family": "Bukowsky", "given": "Colton R." }, "orcid": "0000-0003-3577-8050" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Near-Unity Unselective Absorption in Sparse InP Nanowire Arrays", "ispublished": "pub", "full_text_status": "public", "keywords": "broadband absorber; nanowire; optoelectronic; photovoltaic; waveguide", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: May 16, 2016; Published: September 26, 2016; Publication Date (Web): September 26, 2016. \n\nThis material is based upon work primarily supported by (C.R.B. and H.A.A.) the Engineering Research Center Program of the National Science Foundation and the Office of Energy Efficiency and Renewable Energy of the Department of Energy under NSF Cooperative Agreement No. EEC-1041895 and is also based upon work performed by (W.-H.C. and K.T.F.) the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ph6b00341_si_001.pdf
", "abstract": "We experimentally demonstrate near-unity, unselective absorption, broadband, angle-insensitive, and polarization-independent absorption, in sparse InP nanowire arrays, embedded in flexible polymer sheets via geometric control of waveguide modes in two wire motifs: (i) arrays of tapered wires and (ii) arrays of nanowires with varying radii. Sparse arrays of these structures exhibit enhanced absorption due to strong coupling into the first order azimuthal waveguide modes of individual nanowires; wire radius thus controls the spectral region of the absorption enhancement. Whereas arrays of cylindrical wires with uniform radius exhibit narrowband absorption, arrays of tapered wires and arrays with multiple wire radii expand this spectral region and achieve broadband absorption enhancement. Herein, we present an economic, top-down lithographic/etch fabrication method that enables fabrication of multiple InP nanowire arrays from a single InP wafer with deliberate control of nanowire radius and taper. Using this method, we create sparse tapered and multiradii InP nanowire arrays and demonstrate optical absorption that is broadband (450\u2013900 nm), angle-insensitive, and near-unity (>90%) in roughly 100 nm planar equivalence of InP. These highly absorbing sparse nanowire arrays represent a promising approach to flexible, high efficiency optoelectronic devices, such as photodetectors, solar cells, and photoelectrochemical devices.", "date": "2016-10-19", "date_type": "published", "publication": "ACS Photonics", "volume": "3", "number": "10", "publisher": "American Chemical Society", "pagerange": "1826-1832", "id_number": "CaltechAUTHORS:20161021-142106782", "issn": "2330-4022", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161021-142106782", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsphotonics.6b00341", "primary_object": { "basename": "ph6b00341_si_001.pdf", "url": "https://authors.library.caltech.edu/records/pfpbe-hez09/files/ph6b00341_si_001.pdf" }, "pub_year": "2016", "author_list": "Fountaine, Katherine T.; Cheng, Wen-Hui; et el." }, { "id": "https://authors.library.caltech.edu/records/vmvvn-f6e69", "eprint_id": 70747, "eprint_status": "archive", "datestamp": "2023-08-22 18:55:08", "lastmod": "2023-10-20 23:27:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yalamanchili-S", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Emmer-H-S", "name": { "family": "Emmer", "given": "Hal S." } }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Chen-Christopher-T", "name": { "family": "Chen", "given": "Christopher T." }, "orcid": "0000-0001-5848-961X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Enhanced Absorption and <1% Spectrum-and-Angle-Averaged Reflection in Tapered Microwire Arrays", "ispublished": "pub", "full_text_status": "public", "keywords": "absorption; carrier lifetime; ICPRIE; microwires; reflection; silicon; surface passivation; waveguide", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: May 30, 2016; Publication Date (Web): September 19, 2016. \n\nThis work was supported in part by the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895 (H.S.E. and C.T.C.) and Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. Some of us (C.T.C., H.A.A.) are also supported in part by the U.S. Department of Energy through the Bay Area Photovoltaic Consortium under Award Number DE-EE0004946. We thank Dennis Friedrich for his collaborations for microwave-detected photoconductive decay measurements, Prof. Shu Hu for stimulating discussions, and Carol Garland for her assistance with TEM. This work benefited from use of the Applied Physics and Materials Science Department's Transmission Electron Microscopy Facility. Fabrication was performed in Kavli Nanoscience Institute (KNI) at Caltech, and we thank KNI staff for their assistance during fabrication. Lumerical FDTD simulations for this research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nS. Yalamanchili and H. S. Emmer contributed equally. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ph6b00370_si_001.pdf
", "abstract": "We report ordered, high aspect ratio, tapered Si microwire arrays that exhibit an extremely low angular (0\u00b0 to 50\u00b0) and spectrally averaged reflectivity of <1% of the incident 400\u20131100 nm illumination. After isolating the microwires from the substrate with a polymer infill and peel off process, the arrays were found to absorb 89.1% of angular averaged incident illumination (0\u00b0 to 50\u00b0) in the equivalent volume of a 20 \u03bcm thick Si planar slab, reaching 99.5% of the classical light trapping limit between 400 and 1100 nm. We explain the broadband absorption by enhancement in coupling to waveguide modes due to the tapered microstructure of the arrays. Time-resolved microwave photoconductivity decay measurements yielded charge-carrier lifetimes of 0.75 \u03bcs (more than an order of magnitude higher than vapor\u2013liquid\u2013solid-grown Si microwires) in the tapered microwires, resulting in an implied V_(oc) of 0.655 V. The high absorption and high aspect ratio in these ordered microwire arrays make them an attractive platform for high-efficiency thin-film crystalline Si solar cells and as well as for the photoelectrochemical production of fuels from sunlight.", "date": "2016-10-19", "date_type": "published", "publication": "ACS Photonics", "volume": "3", "number": "10", "publisher": "American Chemical Society", "pagerange": "1854-1861", "id_number": "CaltechAUTHORS:20161003-084500313", "issn": "2330-4022", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161003-084500313", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0004946" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1021/acsphotonics.6b00370", "primary_object": { "basename": "ph6b00370_si_001.pdf", "url": "https://authors.library.caltech.edu/records/vmvvn-f6e69/files/ph6b00370_si_001.pdf" }, "pub_year": "2016", "author_list": "Yalamanchili, Sisir; Emmer, Hal S.; et el." }, { "id": "https://authors.library.caltech.edu/records/kdyj6-gva30", "eprint_id": 70765, "eprint_status": "archive", "datestamp": "2023-08-20 14:12:59", "lastmod": "2023-10-20 23:29:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Solar-Driven Reduction of 1 atm of CO_2 to Formate at 10% Energy-Conversion Efficiency by Use of a TiO_2-Protected III\u2013V Tandem Photoanode in Conjunction with a Bipolar Membrane and a Pd/C Cathode", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: August 2, 2016; Accepted: September 9, 2016; Publication Date (Web): September 9, 2016. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. The authors also thank N. Dalleska (Caltech) for his assistance with measurements and analysis of the ICPMS and TIC data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nz6b00317_si_001.pdf
", "abstract": "A solar-driven CO_2 reduction (CO_2R) cell was constructed, consisting of a tandem GaAs/InGaP/TiO_2/Ni photoanode in 1.0 M KOH(aq) (pH = 13.7) to facilitate the oxygen-evolution reaction (OER), a Pd/C nanoparticle-coated Ti mesh cathode in 2.8 M KHCO_3(aq) (pH = 8.0) to perform the CO_2R reaction, and a bipolar membrane to allow for steady-state operation of the catholyte and anolyte at different bulk pH values. At the operational current density of 8.5 mA cm^(\u20132), in 2.8 M KHCO_3(aq), the cathode exhibited <100 mV overpotential and >94% Faradaic efficiency for the reduction of 1 atm of CO_2(g) to formate. The anode exhibited a 320 \u00b1 7 mV overpotential for the OER in 1.0 M KOH(aq), and the bipolar membrane exhibited \u223c480 mV voltage loss with minimal product crossovers and >90 and >95% selectivity for protons and hydroxide ions, respectively. The bipolar membrane facilitated coupling between two electrodes and electrolytes, one for the CO_2R reaction and one for the OER, that typically operate at mutually different pH values and produced a lower total cell overvoltage than known single-electrolyte CO_2R systems while exhibiting \u223c10% solar-to-fuels energy-conversion efficiency.", "date": "2016-10-14", "date_type": "published", "publication": "ACS Energy Letters", "volume": "1", "number": "4", "publisher": "American Chemical Society", "pagerange": "764-770", "id_number": "CaltechAUTHORS:20161003-141800305", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161003-141800305", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.6b00317", "primary_object": { "basename": "nz6b00317_si_001.pdf", "url": "https://authors.library.caltech.edu/records/kdyj6-gva30/files/nz6b00317_si_001.pdf" }, "pub_year": "2016", "author_list": "Zhou, Xinghao; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/rjc7h-j7y77", "eprint_id": 69299, "eprint_status": "archive", "datestamp": "2023-08-22 18:52:02", "lastmod": "2023-10-20 16:46:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Berger-A-D", "name": { "family": "Berger", "given": "Alan" } }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Coridan-R-H", "name": { "family": "Coridan", "given": "Robert" }, "orcid": "0000-0003-1916-4446" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Haussener-S", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Modestino-M-A", "name": { "family": "Modestino", "given": "Miguel A." }, "orcid": "0000-0003-2100-7335" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew M." }, "orcid": "0000-0003-4682-9757" }, { "id": "Singh-M-R", "name": { "family": "Singh", "given": "Meenesh R." }, "orcid": "0000-0002-3638-8866" }, { "id": "Stevens-J-C", "name": { "family": "Stevens", "given": "John C." } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Walczak-K-A", "name": { "family": "Walczak", "given": "Karl" } } ] }, "title": "Modeling, Simulation, and Implementation of Solar-Driven Water-Splitting Devices", "ispublished": "pub", "full_text_status": "restricted", "keywords": "device architecture; hydrogen; modeling; photoelectrochemistry; solar-driven water splitting", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. \n\nReceived: November 11, 2015. Revised: January 31, 2016. Version of Record online: 27 Jul 2016. \n\nWe would like to thank the community of researchers whose work is reflected in this Review, especially those past and present at JCAP. This material is based upon work performed at the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A. acknowledges support from the U.S. Department of Energy under Award No. DEEE0006963.", "abstract": "An integrated cell for the solar-driven splitting of water consists of multiple functional components and couples various photoelectrochemical (PEC) processes at different length and time scales. The overall solar-to-hydrogen (STH) conversion efficiency of such a system depends on the performance and materials properties of the individual components as well as on the component integration, overall device architecture, and system operating conditions. This Review focuses on the modeling- and simulation-guided development and implementation of solar-driven water-splitting prototypes from a holistic viewpoint that explores the various interplays between the components. The underlying physics and interactions at the cell level is are reviewed and discussed, followed by an overview of the use of the cell model to provide target properties of materials and guide the design of a range of traditional and unique device architectures.", "date": "2016-10-10", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "55", "number": "42", "publisher": "Wiley", "pagerange": "12974-12988", "id_number": "CaltechAUTHORS:20160729-070531307", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160729-070531307", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0006963" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/anie.201510463", "pub_year": "2016", "author_list": "Xiang, Chengxiang; Weber, Adam Z.; et el." }, { "id": "https://authors.library.caltech.edu/records/gscf9-tq458", "eprint_id": 70252, "eprint_status": "archive", "datestamp": "2023-08-20 14:10:11", "lastmod": "2023-10-20 22:03:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "A." }, "orcid": "0000-0003-2386-3848" }, { "id": "Li-Guiji", "name": { "family": "Li", "given": "G." } }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "L." }, "orcid": "0000-0002-7052-266X" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "S. K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "F. M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Yan-Q", "name": { "family": "Yan", "given": "Q." } }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Neaton-Jeffrey-B", "name": { "family": "Neaton", "given": "J. B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "The role of the CeO_2/BiVO_4 interface in optimized Fe-Ce oxide coatings for solar fuels photoanodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 6th June 2016; Accepted 26th August 2016; First published online 09 Sep 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). A. Shinde, G. Li and L. Zhou contributed equally to this work. The authors thank Ian Sharp for insightful discussions and Xinghao Zhou for assistance with AFM experiments.\n\nSupplemental Material - c6ta04746g1_si.pdf
", "abstract": "Solar fuel generators entail a high degree of materials integration, and efficient photoelectrocatalysis of the constituent reactions hinges upon the establishment of highly functional interfaces. The recent application of high throughput experimentation to interface discovery for solar fuels photoanodes has revealed several surprising and promising mixed-metal oxide coatings for BiVO_4. Using sputter deposition of composition and thickness gradients on a uniform BiVO_4 film, we systematically explore photoanodic performance as a function of the composition and loading of Fe\u2013Ce oxide coatings. This combinatorial materials integration study not only enhances the performance of this new class of materials but also identifies CeO_2 as a critical ingredient that merits detailed study. A heteroepitaxial CeO_2(001)/BiVO_4(010) interface is identified in which Bi and V remain fully coordinated to O such that no surface states are formed. Ab initio calculations of the integrated materials and inspection of the electronic structure reveals mechanisms by which CeO_2 facilitates charge transport while mitigating deleterious recombination. The results support the observations that addition of Ce to BiVO_4 coatings greatly enhances photoelectrocatalytic activity, providing an important strategy for developing a scalable solar fuels technology.", "date": "2016-10-07", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "4", "number": "37", "publisher": "Royal Society of Chemistry", "pagerange": "14356-14363", "id_number": "CaltechAUTHORS:20160909-133249863", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160909-133249863", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c6ta04746g", "primary_object": { "basename": "c6ta04746g1_si.pdf", "url": "https://authors.library.caltech.edu/records/gscf9-tq458/files/c6ta04746g1_si.pdf" }, "pub_year": "2016", "author_list": "Shinde, A.; Li, G.; et el." }, { "id": "https://authors.library.caltech.edu/records/m5556-fy940", "eprint_id": 70140, "eprint_status": "archive", "datestamp": "2023-08-20 14:10:02", "lastmod": "2023-10-20 21:51:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Johnson-S-I", "name": { "family": "Johnson", "given": "Samantha I." } }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Selectivity for HCO\u2082^\u2013 over H\u2082 in the Electrochemical Catalytic Reduction of CO\u2082 by (POCOP)IrH\u2082", "ispublished": "pub", "full_text_status": "public", "keywords": "density functional theory, electrochemical CO2 reduction, reaction mechanism, chemoselectivity, hydricity, hydrogen evolution", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 21, 2016; Revised: August 10, 2016; Publication Date (Web): August 15, 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.I.J. is supported by a National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469 and by the generous support of the Resnick Sustainability Institute. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs6b01755_si_001.pdf
Supplemental Material - cs6b01755_si_002.xyz
", "abstract": "It has been demonstrated experimentally that electrochemical CO_2 reduction catalyzed by (POCOP)IrH_2 ([C_6H_3-2,6-[OP(tBu)_2]_2]IrH_2) produces formate without significant H_2. We use first-principles density functional theory (M06) including Poisson\u2013Boltzmann solvation to determine the detailed atomistic mechanism and illuminate strategies for designing formate-selective catalysts. A mechanism involving hydride transfer from Ir^(III) dihydride explains the selectivity for formate over H_2 and is corroborated by reduction potential (irreversible reduction of (POCOP)Ir(H)(NCMe)_2^+ at ca. \u22121.3 V vs NHE, in comparison to \u22121.31 V vs NHE calculated for one-electron reduction of Ir^(III)(H)(NCMe)_2^+) and turnover frequency. We find that several thermodynamically favorable pathways exist for the hydrogen evolution reaction (HER) from both Ir^(III)(H)_2 and Ir^I\u2013H^\u2013 but are kinetically hindered, posing computed activation barriers above 25 kcal/mol at pH 7. However, with formate or bicarbonate acting as cocatalyst, the barriers are lowered to 18.8 kcal/mol. The preference of (POCOP)Ir to form a dihydride instead of a dihydrogen adduct also disfavors the HER and facilitates catalyst regeneration. In contrast, substituting cobalt for iridium raises the barrier for hydride transfer to CO_2 by 12.0 kcal/mol and lowers the required reduction potential to \u22121.65 V vs NHE. Calculated driving forces for hydride transfer from Ir^I and Ir^(III) intermediates illustrate different strategies for positioning the hydricity relative to the thermodynamic hydricities of H_2/H^+ and HCOO^\u2013/CO_2. The data support an approach of selecting a hydricity that is just thermodynamically able to reduce CO_2. The effect of solvation on calculated driving forces for hydride transfer is also discussed.", "date": "2016-10-07", "date_type": "published", "publication": "ACS Catalysis", "volume": "6", "number": "10", "publisher": "American Chemical Society", "pagerange": "6362-6371", "id_number": "CaltechAUTHORS:20160902-085020686", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160902-085020686", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.6b01755", "primary_object": { "basename": "cs6b01755_si_001.pdf", "url": "https://authors.library.caltech.edu/records/m5556-fy940/files/cs6b01755_si_001.pdf" }, "related_objects": [ { "basename": "cs6b01755_si_002.xyz", "url": "https://authors.library.caltech.edu/records/m5556-fy940/files/cs6b01755_si_002.xyz" } ], "pub_year": "2016", "author_list": "Johnson, Samantha I.; Nielsen, Robert J.; et el." }, { "id": "https://authors.library.caltech.edu/records/zntez-7b176", "eprint_id": 68522, "eprint_status": "archive", "datestamp": "2023-08-20 13:58:38", "lastmod": "2023-10-19 22:15:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saive-R", "name": { "family": "Saive", "given": "Rebecca" }, "orcid": "0000-0001-7420-9155" }, { "id": "Borsuk-A-M", "name": { "family": "Borsuk", "given": "Aleca M." } }, { "id": "Emmer-H-S", "name": { "family": "Emmer", "given": "Hal S." } }, { "id": "Bukowsky-C-R", "name": { "family": "Bukowsky", "given": "Colton R." }, "orcid": "0000-0003-3577-8050" }, { "id": "Lloyd-J-V", "name": { "family": "Lloyd", "given": "John V." } }, { "id": "Yalamanchili-S", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Effectively Transparent Front Contacts for Optoelectronic Devices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. This is an open access article under the terms of the Creative Commons Attribution-NonCommercial License , which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes. The copyright line of this paper was changed 1 August 2016 after initial publication. \n\nManuscript Received: 7 APR 2016. Manuscript Revised: 17 MAY 2016. Version of Record online: 10 JUN 2016. \n\nThe information, data, or work presented herein was funded in part by the U.S. Department of Energy, Energy Efficiency and Renewable Energy Program, under Award Number DE-EE0006335 The lithographic printing (C.R.B. and S.Y.) was supported by the Bay Area Photovoltaics Consortium under Award Number DE-EE0004946. One of us (A.M.B.) was supported by the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895. S.Y. acknowledges the Kavli Nanoscience Institute and the Joint Center for Artificial Photosynthesis. The authors acknowledge Mathieu Boccard (Arizona State University) for providing the solar cells used to carry out this study. The authors thank Cristofer A. Flowers (California Institute of Technology) for helpful discussion and Lucas Meza (California Institute of Technology) for two-photon lithography advice.\n\nPublished - Saive_et_al-2016-Advanced_Optical_Materials.pdf
Supplemental Material - adom201600252-sup-0001-S1.pdf
", "abstract": "Effectively transparent front contacts for optoelectronic devices achieve a measured transparency of up to 99.9% and a measured sheet resistance of 4.8 \u03a9 sq^(\u22121). The 3D microscale triangular cross-section grid fingers redirect incoming photons efficiently to the active semiconductor area and can replace standard grid fingers as well as transparent conductive oxide layers in optoelectronic devices.", "date": "2016-10", "date_type": "published", "publication": "Advanced Optical Materials", "volume": "4", "number": "10", "publisher": "Wiley", "pagerange": "1470-1474", "id_number": "CaltechAUTHORS:20160620-101424565", "issn": "2195-1071", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160620-101424565", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0006335" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0004946" }, { "agency": "NSF", "grant_number": "EEC-1041895" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/adom.201600252", "primary_object": { "basename": "Saive_et_al-2016-Advanced_Optical_Materials.pdf", "url": "https://authors.library.caltech.edu/records/zntez-7b176/files/Saive_et_al-2016-Advanced_Optical_Materials.pdf" }, "related_objects": [ { "basename": "adom201600252-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/zntez-7b176/files/adom201600252-sup-0001-S1.pdf" } ], "pub_year": "2016", "author_list": "Saive, Rebecca; Borsuk, Aleca M.; et el." }, { "id": "https://authors.library.caltech.edu/records/g0g5n-k0628", "eprint_id": 69086, "eprint_status": "archive", "datestamp": "2023-08-20 13:53:41", "lastmod": "2023-10-20 16:31:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Jermyn-A-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Cubic Nonlinearity Driven Up-Conversion in High-Field Plasmonic Hot Carrier Systems", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: April 5, 2016; Revised: June 20, 2016; Publication Date (Web): June 20, 2016. \n\nSpecial Issue: Richard P. Van Duyne Festschrift. \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.S.J. acknowledges support from the Barry M. Goldwater Scholarship. The authors acknowledge support from NG NEXT at Northrop Grumman Corporation. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. \n\nThe authors declare no competing financial interest.", "abstract": "Surface plasmon resonances confine electromagnetic fields to the nanoscale, producing high field strengths suitable for exploiting nonlinear optical properties. We examine the prospect of detecting and utilizing one such property in plasmonic metals: the imaginary part of the cubic susceptibility, which corresponds to two plasmons decaying together to produce high energy carriers. Here we present ab initio predictions of the rates and carrier distributions generated by direct interband and phonon-assisted intraband transitions in one and two-plasmon decay. We propose detection of the higher energy carriers generated from two-plasmon decays that are inaccessible in one-plasmon decay as a viable signature of these processes in ultrafast experiments.", "date": "2016-09-22", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "120", "number": "37", "publisher": "American Chemical Society", "pagerange": "21056-21062", "id_number": "CaltechAUTHORS:20160718-092335284", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160718-092335284", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Barry M. Goldwater Scholarship" }, { "agency": "Northrop Grumman Corporation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1021/acs.jpcc.6b03463", "pub_year": "2016", "author_list": "Narang, Prineha; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/jmg3n-bvy80", "eprint_id": 70196, "eprint_status": "archive", "datestamp": "2023-08-20 13:48:47", "lastmod": "2023-10-20 21:56:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yao-Wei", "name": { "family": "Huang", "given": "Yao-Wei" } }, { "id": "Lee-Ho-Wai-Howard", "name": { "family": "Lee", "given": "Ho Wai Howard" } }, { "id": "Sokhoyan-R", "name": { "family": "Sokhoyan", "given": "Ruzan" }, "orcid": "0000-0003-4599-6350" }, { "id": "Pala-R-A", "name": { "family": "Pala", "given": "Ragip A." } }, { "id": "Thyagarajan-K", "name": { "family": "Thyagarajan", "given": "Krishnan" } }, { "id": "Han-Seunghoon", "name": { "family": "Han", "given": "Seunghoon" } }, { "id": "Tsai-Din-Ping", "name": { "family": "Tsai", "given": "Din Ping" }, "orcid": "0000-0002-0883-9906" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Gate-Tunable Conducting Oxide Metasurfaces", "ispublished": "pub", "full_text_status": "public", "keywords": "Metasurfaces, transparent conducting oxides, field-effect modulation, phase modulation, epsilon-near-zero materials, plasmonics, modulators, beam steering", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: February 7, 2016. Revised: August 6, 2016. \n\nThis work was supported by Samsung Electronics and by the Hybrid Nanophotonics Multidisciplinary University Research Initiative Grant (Air Force Office of Scientific Research, FA9550-12-1-0024). The conducting oxide material synthesis design and characterization was supported by the U.S. Department of Energy (DOE) Office of Science grant DEFG02-07ER46405 (K.T. and H.A.A.) and used facilities supported by the Kavli Nanoscience Institute (KNI) and Joint Center for Artificial Photosynthesis (JCAP) at Caltech. Y.W.H. and D.P.T. acknowledge the support from Ministry of Science and Technology, Taiwan (Grants 103-2911-I-002-594, 104-2745-M-002-003-ASP, and 105-2745-002-002-ASP) and Academia Sinica (Grant AS-103-TP-A06). K.T. acknowledges funding from the Swiss National Science Foundation (Grant 151853). The authors would like to thank Rui Liu for Al2O3 deposition and Katherine Fountaine for useful discussions.\n\nAuthor Contributions: (Y.W.H. and H.W.H.L.) contributed equally to this work. Y.W.H., H.W.H.L., R.S., and H.A.A. designed and conceived the experiments. Y.W.H. and H.W.H.L. fabricated the samples. Y.W.H., H.W.H.L., and R.A.P developed the measurement setup and performed the experiments. Y.W.H., H.W.H.L., and K.T. performed materials characterizations. Y.W.H. and R.S. performed numerical simulations. Y.W.H., H.W.H.L., R.S., R.A.P., K.T., S.H., and H.A.A. wrote the paper. All authors discussed the results and commented on the manuscript. \n\nThe authors declare no competing financial interest.\n\nSubmitted - 1511.09380.pdf
Supplemental Material - nl6b00555_si_001.pdf
", "abstract": "Metasurfaces composed of planar arrays of subwavelength artificial structures show promise for extraordinary light manipulation. They have yielded novel ultrathin optical components such as flat lenses, wave plates, holographic surfaces, and orbital angular momentum manipulation and detection over a broad range of the electromagnetic spectrum. However, the optical properties of metasurfaces developed to date do not allow for versatile tunability of reflected or transmitted wave amplitude and phase after their fabrication, thus limiting their use in a wide range of applications. Here, we experimentally demonstrate a gate-tunable metasurface that enables dynamic electrical control of the phase and amplitude of the plane wave reflected from the metasurface. Tunability arises from field-effect modulation of the complex refractive index of conducting oxide layers incorporated into metasurface antenna elements which are configured in reflectarray geometry. We measure a phase shift of 180\u00b0 and \u223c30% change in the reflectance by applying 2.5 V gate bias. Additionally, we demonstrate modulation at frequencies exceeding 10 MHz and electrical switching of \u00b11 order diffracted beams by electrical control over subgroups of metasurface elements, a basic requirement for electrically tunable beam-steering phased array metasurfaces. In principle, electrically gated phase and amplitude control allows for electrical addressability of individual metasurface elements and opens the path to applications in ultrathin optical components for imaging and sensing technologies, such as reconfigurable beam steering devices, dynamic holograms, tunable ultrathin lenses, nanoprojectors, and nanoscale spatial light modulators.", "date": "2016-09-14", "date_type": "published", "publication": "Nano Letters", "volume": "16", "number": "9", "publisher": "American Chemical Society", "pagerange": "5319-5325", "id_number": "CaltechAUTHORS:20160907-142523365", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160907-142523365", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Samsung Electronics" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0024" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-07ER46405" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Joint Center for Artificial Photosynthesis" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "103-2911-I-002-594" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "104-2745-M-002-003-ASP" }, { "agency": "Ministry of Science and Technology (Taipei)", "grant_number": "105-2745-002-002-ASP" }, { "agency": "Academia Sinica", "grant_number": "AS-103-TP-A06" }, { "agency": "Swiss National Science Foundation (SNSF)", "grant_number": "151853" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.6b00555", "primary_object": { "basename": "1511.09380.pdf", "url": "https://authors.library.caltech.edu/records/jmg3n-bvy80/files/1511.09380.pdf" }, "related_objects": [ { "basename": "nl6b00555_si_001.pdf", "url": "https://authors.library.caltech.edu/records/jmg3n-bvy80/files/nl6b00555_si_001.pdf" } ], "pub_year": "2016", "author_list": "Huang, Yao-Wei; Lee, Ho Wai Howard; et el." }, { "id": "https://authors.library.caltech.edu/records/ddeg4-mch47", "eprint_id": 70185, "eprint_status": "archive", "datestamp": "2023-08-22 18:42:08", "lastmod": "2023-10-20 21:55:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-Dan-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Liu-Guiji", "name": { "family": "Liu", "given": "Guiji" }, "orcid": "0000-0002-3943-4119" }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" } ] }, "title": "Discovery of Fe\u2013Ce Oxide/BiVO\u2084 Photoanodes through Combinatorial Exploration of Ni\u2013Fe\u2013Co\u2013Ce Oxide Coatings", "ispublished": "pub", "full_text_status": "public", "keywords": "high-throughput experimentation; materials integration; oxygen evolution reaction; photoanode; solar fuels", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: June 5, 2016. Accepted: August 23, 2016. Publication Date (Web): August 23, 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). \n\nAuthor Contributions: A.S. and D.G. contributed equally to this work. \n\nhe authors declare no competing financial interest.\n\nSupplemental Material - am6b06714_si_001.pdf
", "abstract": "An efficient photoanode is a prerequisite for a viable solar fuels technology. The challenges to realizing an efficient photoanode include the integration of a semiconductor light absorber and a metal oxide electrocatalyst to optimize corrosion protection, light trapping, hole transport, and photocarrier recombination sites. To efficiently explore metal oxide coatings, we employ a high-throughput methodology wherein a uniform BiVO\u2084 film is coated with 858 unique metal oxide coatings covering a range of metal oxide loadings and the full (Ni\u2013Fe\u2013Co\u2013Ce)O\u2093 pseudoquaternary composition space. Photoelectrochemical characterization of the photoanodes reveals that specific combinations of metal oxide composition and loading provide up to a 13-fold increase in the maximum photoelectrochemical power generation for oxygen evolution in pH 13 electrolyte. Through mining of the high-throughput data we identify composition regions that form improved interfaces with BiVO\u2084. Of particular note, integrated photoanodes with catalyst compositions in the range Fe_((0.4\u20130.6))Ce_((0.6\u20130.4))O\u2093 exhibit high interface quality and excellent photoelectrochemical power conversion. Scaled-up inkjet-printed electrodes and photoanodic electrodeposition of this composition on BiVO\u2084 confirms the discovery and the synthesis-independent interface improvement of (Fe\u2013Ce)O\u2093 coatings on BiVO\u2084.", "date": "2016-09-14", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "8", "number": "36", "publisher": "American Chemical Society", "pagerange": "23696-23705", "id_number": "CaltechAUTHORS:20160907-090003256", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160907-090003256", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.6b06714", "primary_object": { "basename": "am6b06714_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ddeg4-mch47/files/am6b06714_si_001.pdf" }, "pub_year": "2016", "author_list": "Shinde, Aniketa; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/ten2s-ypj95", "eprint_id": 72293, "eprint_status": "archive", "datestamp": "2023-08-22 18:40:21", "lastmod": "2023-10-23 20:36:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wang-Ruirui", "name": { "family": "Wang", "given": "Ruirui" } }, { "id": "Pan-Kecheng", "name": { "family": "Pan", "given": "Kecheng" } }, { "id": "Han-Dandan", "name": { "family": "Han", "given": "Dandan" } }, { "id": "Jiang-Jingjing", "name": { "family": "Jiang", "given": "Jingjing" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Zhang-Lu", "name": { "family": "Zhang", "given": "Lu" } }, { "id": "Xiang-Xu", "name": { "family": "Xiang", "given": "Xu" } } ] }, "title": "Solar-Driven H_2O_2 Generation From H_2O and O_2 Using Earth-Abundant Mixed-Metal Oxide@Carbon Nitride Photocatalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "hydrogen peroxide; mixed metal oxide; oxygen reduction; photocatalysis; sustainable chemistry", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nIssue online: 6 September 2016; Version of record online: 3 August 2016; Manuscript Received: 26 May 2016. \n\nFunded by:\nNational Natural Science Foundation of China. Grant Number: 2014CB932104; NSFC; Beijing Natural Science Foundation. Grant Number: 2152022; Fundamental Research Funds for the Central Universities. Grant Number: YS1406; Joint Center for Artificial Photosynthesis. Grant Number: DE-SC0004993.\n\nSupplemental Material - cssc201600705-sup-0001-misc_information.pdf
", "abstract": "Light-driven generation of H_2O_2 only from water and molecular oxygen could be an ideal pathway for clean production of solar fuels. In this work, a mixed metal oxide/graphitic-C_3N_4 (MMO@C_3N_4) composite was synthesized as a dual-functional photocatalyst for both water oxidation and oxygen reduction to generate H_2O_2. The MMO was derived from a NiFe-layered double hydroxide (LDH) precursor for obtaining a high dispersion of metal oxides on the surface of the C_3N_4 matrix. The C_3N_4 is in the graphitic phase and the main crystalline phase in MMO is cubic NiO. The XPS analyses revealed the doping of Fe^(3+) in the dominant NiO phase and the existence of surface defects in the C3N4 matrix. The formation and decomposition kinetics of H_2O_2 on the MMO@C_3N_4 and the control samples, including bare MMO, C_3N_4 matrix, Ni- or Fe-loaded C_3N_4 and a simple mixture of MMO and C_3N_4, were investigated. The MMO@C_3N_4 composite produced 63 \u03bcmol\u2009L^(\u22121) of H_2O_2 in 90 min in acidic solution (pH 3) and exhibited a significantly higher rate of production for H_2O_2 relative to the control samples. The positive shift of the valence band in the composite and the enhanced water oxidation catalysis by incorporating the MMO improved the light-induced hole collection relative to the bare C_3N_4 and resulted in the enhanced H_2O_2 formation. The positively shifted conduction band in the composite also improved the selectivity of the two-electron reduction of molecular oxygen to H_2O_2.", "date": "2016-09-08", "date_type": "published", "publication": "ChemSusChem", "volume": "9", "number": "17", "publisher": "Wiley", "pagerange": "2470-2479", "id_number": "CaltechAUTHORS:20161128-081718603", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161128-081718603", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Natural Science Foundation of China", "grant_number": "2014CB932104" }, { "agency": "Beijing Natural Science Foundation", "grant_number": "2152022" }, { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "YS1406" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201600705", "primary_object": { "basename": "cssc201600705-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/ten2s-ypj95/files/cssc201600705-sup-0001-misc_information.pdf" }, "pub_year": "2016", "author_list": "Wang, Ruirui; Pan, Kecheng; et el." }, { "id": "https://authors.library.caltech.edu/records/57b63-0a961", "eprint_id": 68756, "eprint_status": "archive", "datestamp": "2023-08-22 18:39:14", "lastmod": "2023-10-20 15:41:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Axnanda-S", "name": { "family": "Axnanda", "given": "Stephanus" } }, { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter" }, "orcid": "0000-0002-8693-4562" }, { "id": "Hussain-Z", "name": { "family": "Hussain", "given": "Zahid" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Liu-Zhi", "name": { "family": "Liu", "given": "Zhi" } }, { "id": "Nilsson-A", "name": { "family": "Nilsson", "given": "Anders" } }, { "id": "Bell-A-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Friebel-D", "name": { "family": "Friebel", "given": "Daniel" } } ] }, "title": "Operando Analyses of Solar Fuels Light Absorbers and Catalysts", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Catalysis; Semiconductors; Protection; operando spectroscopy; artificial photosynthesis", "note": "\u00a9 2016 Elsevier Ltd. \n\nReceived 11 December 2015, Revised 31 May 2016, Accepted 1 June 2016, Available online 6 June 2016. \n\nThis work was supported by the Office of Science of the U.S. Department of Energy (DOE) through award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis. The Advanced Light Source acknowledges support by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract no. DE-AC02-05CH11231. XAS data collection was carried out at Stanford Synchrotron Radiation Lightsource, a National User Facility operated by Stanford University on behalf of the U.S. Department of Energy, Office of Basic Energy Sciences. Computational work was carried out through NERSC computational resources under DOE Contract No. DE-AC02-05CH11231.", "abstract": "Operando synchrotron radiation photoelectron spectroscopy (SRPES) in the tender X-ray energy range has been used to obtain information on the energy-band relations of semiconductor and metal-covered semiconductor surfaces while in direct contact with aqueous electrolytes under potentiostatic control. The system that was investigated consists of highly doped Si substrates that were conformally coated with \u223c70 nm titania films produced by atomic-layer deposition. The TiO2/electrolyte and the Si/TiO2/Ni electrolyte interfaces were then analyzed by synchrotron radiation photoelectron spectroscopy. The PES data provided a determination of the flat-band position and identified regions of applied potential in which Fermi level pinning, depletion, or accumulation conditions occurred. Operando X-ray absorption spectroscopy (XAS) techniques were additionally used to investigate the properties of heterogeneous electrocatalysts for the oxygen-evolution reaction. Operando XAS including the pre-edge, edge and EXAFS regions allowed the development of a detailed picture of the catalysts under operating conditions, and elucidated the changes that in the physical and electronic structure of the catalyst that accompanied increases in the applied potential. Specifically, XAS data, combined with DFT studies, indicated that the activity of the electrocatalyst correlated with the formation of Fe dopant sites in \u03b3-NiOOH.", "date": "2016-09-01", "date_type": "published", "publication": "Electrochimica Acta", "volume": "211", "publisher": "Elsevier", "pagerange": "711-719", "id_number": "CaltechAUTHORS:20160629-130400375", "issn": "0013-4686", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160629-130400375", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.electacta.2016.06.006", "pub_year": "2016", "author_list": "Lewerenz, Hans-Joachim; Lichterman, Michael F.; et el." }, { "id": "https://authors.library.caltech.edu/records/yprkq-h5988", "eprint_id": 68537, "eprint_status": "archive", "datestamp": "2023-08-22 18:33:23", "lastmod": "2023-10-19 22:16:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Regulating the Product Distribution of CO Reduction by the Atomic-Level Structural Modification of the Cu Electrode Surface", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Selective reduction of CO to ethanol on Cu(511) in alkaline solution at low overpotential; Operando generation of Cu(511) electrode surface from polycrystalline Cu; Operando electrochemical scanning tunneling microscopy (OECSTM); Differential electrochemical mass spectrometry (DEMS); Seriatim OECSTM-DEMS", "note": "\u00a9 2016 Springer Science+Business Media New York. \n\nPublished online: 7 June 2016.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "Cu catalyzes the electrochemical reduction of CO_2 or CO to an assortment of products, a behavior that is a detriment when only one reduced compound is desired. The present article provides an example in which, through the atomic-level control of the structure of the Cu electrode surface, the yield distribution is regulated to generate only one product. The reaction investigated was the preferential reduction of CO to C_2H_5OH on Cu at a low overpotential in alkaline solution. Experimental measurements combined electrochemical scanning tunneling microscopy (ECSTM) and differential electrochemical mass spectrometry (DEMS). An atomically ordered Cu(100) surface, prepared from either a single crystal or by Cu(pc)-to-Cu(100) reconstruction, did not produce ethanol. When the surfaces were subjected to monolayer-limited Cu\u2194Cu_2O cycles, only the reconstructed surface underwent an additional structural transformation that spawned the selective production of ethanol at a potential 645 mV lower than that which generates multiple products. Quasi-operando ECSTM indicated transformation to an ordered stepped surface, Cu(S)\u2009\u2212\u2009[3(100)\u2009\u00d7\u2009(111)], or Cu(511). The non-selective, multiple-product Cu-catalyzed reduction of CO had thus been regulated to yield only one liquid fuel by an atomic-level structural modification of the electrode surface.", "date": "2016-09", "date_type": "published", "publication": "Electrocatalysis", "volume": "7", "number": "5", "publisher": "Springer", "pagerange": "391-399", "id_number": "CaltechAUTHORS:20160620-134104006", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160620-134104006", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-016-0314-1", "pub_year": "2016", "author_list": "Kim, Youn-Geun; Javier, Alnald; et el." }, { "id": "https://authors.library.caltech.edu/records/1d8b1-mjy92", "eprint_id": 67884, "eprint_status": "archive", "datestamp": "2023-08-20 13:04:04", "lastmod": "2023-10-19 22:02:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-Ana-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Ab initio phonon coupling and optical response of hot electrons in plasmonic metals", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Physical Society.\n\nReceived 1 February 2016; revised manuscript received 26 July 2016; published 11 August 2016.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.N. and W.A.G. acknowledge financial support from NG NEXT for this project. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE \"Light-Material Interactions in Energy Conversion\" Energy Frontier Research Center (Grant No. DE-SC0001293).\n\nPublished - PhysRevB.94.075120.pdf
Submitted - 1602.00625v1.pdf
Supplemental Material - Ag_ImEpsilon.dat
Supplemental Material - Ag_ReEpsilon.dat
Supplemental Material - Al_ImEpsilon.dat
Supplemental Material - Al_ReEpsilon.dat
Supplemental Material - Au_ImEpsilon.dat
Supplemental Material - Au_ReEpsilon.dat
Supplemental Material - Cu_ImEpsilon.dat
Supplemental Material - Cu_ReEpsilon.dat
Supplemental Material - SI.pdf
", "abstract": "Ultrafast laser measurements probe the nonequilibrium dynamics of excited electrons in metals with increasing temporal resolution. Electronic structure calculations can provide a detailed microscopic understanding of hot electron dynamics, but a parameter-free description of pump-probe measurements has not yet been possible, despite intensive research, because of the phenomenological treatment of electron-phonon interactions. We present ab initio predictions of the electron-temperature dependent heat capacities and electron-phonon coupling coefficients of plasmonic metals. We find substantial differences from free-electron and semiempirical estimates, especially in noble metals above transient electron temperatures of 2000 K, because of the previously neglected strong dependence of electron-phonon matrix elements on electron energy. We also present first-principles calculations of the electron-temperature dependent dielectric response of hot electrons in plasmonic metals, including direct interband and phonon-assisted intraband transitions, facilitating complete theoretical predictions of the time-resolved optical probe signatures in ultrafast laser experiments.", "date": "2016-08", "date_type": "published", "publication": "Physical Review B", "volume": "94", "number": "7", "publisher": "American Physical Society", "pagerange": "Art. No. 075120", "id_number": "CaltechAUTHORS:20160613-140325024", "issn": "2469-9950", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160613-140325024", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1175", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Resnick-Sustainability-Institute" } ] }, "doi": "10.1103/PhysRevB.94.075120", "primary_object": { "basename": "1602.00625v1.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/1602.00625v1.pdf" }, "related_objects": [ { "basename": "Ag_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Ag_ImEpsilon.dat" }, { "basename": "Cu_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Cu_ReEpsilon.dat" }, { "basename": "Cu_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Cu_ImEpsilon.dat" }, { "basename": "PhysRevB.94.075120.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/PhysRevB.94.075120.pdf" }, { "basename": "SI.pdf", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/SI.pdf" }, { "basename": "Ag_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Ag_ReEpsilon.dat" }, { "basename": "Al_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Al_ImEpsilon.dat" }, { "basename": "Al_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Al_ReEpsilon.dat" }, { "basename": "Au_ImEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Au_ImEpsilon.dat" }, { "basename": "Au_ReEpsilon.dat", "url": "https://authors.library.caltech.edu/records/1d8b1-mjy92/files/Au_ReEpsilon.dat" } ], "pub_year": "2016", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/b68j8-9z536", "eprint_id": 60755, "eprint_status": "archive", "datestamp": "2023-08-20 13:01:05", "lastmod": "2023-10-24 21:09:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Influence of Redox-Inactive Cations on the Structure and Electrochemical Reactivity of Synthetic Birnessite, a Heterogeneous Analog for the Oxygen-Evolving Complex", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: July 21, 2015, Revised: September 10, 2015, Publication Date (Web): September 30, 2015. \n\nThis article is part of the Kohei Uosaki Festschrift special issue. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993.", "abstract": "Electrochemical protocols were developed for the facile potentiostatic deposition of birnessite films, supported on Au substrates, to serve as a structural motif for oxygen evolution reaction electrocatalysts. The elimination of prolonged cation-exchange submersion dramatically reduced the synthesis time scale from days to minutes. The electrodeposited films were characterized using a combination of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, scanning tunneling microscopy, and X-ray photoelectron spectroscopy. The prepared birnessite films were crystalline, monophasic oxide materials that contained Mn^(3+), Mn^(4+), traces of Mn^(2+), and the intercalant of choice. Redox-inactive Na^+, Ca^(2+), Sr^(2+), Y^(3+), and Zn^(2+) cations showed minimal influence on the voltammetric behavior of birnessite in the presence of Mn^(2+)(aq). Slightly more significant effects emerged during potential cycling and chronopotentiometry of birnessite films in 0.1 M NaOH. The potential needed to sustain a current density of 10 mA\u202fcm^(\u20132) in 0.1 M NaOH increased according to the sequence Na^+ < Ca^(2+) < Sr^(2+) < Y^(3+) < Zn^(2+). The sequence, with slight inversions in the order, was reminiscent of the trend in the heterometal-dependent modulation of the half-wave potential of the redox couple Mn^(3+)Mn_2^(4+)/Mn_3^(4+) in nonaqueous solutions of heterometallic manganese\u2013dioxido cluster systems. Unlike the case of the homogeneous cluster catalysts, the electrochemical reactivity of intercalated birnessite films did not vary linearly with the pK_a of the redox-inactive cations.", "date": "2016-07-28", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "120", "number": "29", "publisher": "American Chemical Society", "pagerange": "15618-15631", "id_number": "CaltechAUTHORS:20151005-112626822", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151005-112626822", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.5b07028", "pub_year": "2016", "author_list": "Baricuatro, Jack H.; Saadi, Fadl H.; et el." }, { "id": "https://authors.library.caltech.edu/records/x8dmd-9mc82", "eprint_id": 68689, "eprint_status": "archive", "datestamp": "2023-08-22 18:19:07", "lastmod": "2023-10-19 23:16:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sieh-D", "name": { "family": "Sieh", "given": "Daniel" } }, { "id": "Kubiak-C-P", "name": { "family": "Kubiak", "given": "Clifford P." }, "orcid": "0000-0003-2186-488X" } ] }, "title": "A Series of Diamagnetic Pyridine Monoimine Rhenium Complexes with Different Degrees of Metal-to-Ligand Charge Transfer: Correlating ^(13)C NMR Chemical Shifts with Bond Lengths in Redox-Active Ligands", "ispublished": "pub", "full_text_status": "public", "keywords": "alpha diimines; NMR spectroscopy; redox-active ligands; rhenium; X-ray crystallography", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. \n\nReceived: February 14, 2016. Version of Record online: 20 Jun 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Michael Takase, Lawrence\u2005M. Henling and David\u2005G. VanderVelde are thanked for their invaluable work in the X-ray (M.T. and L.M.H.) and NMR (D.G.V.V) facilities at Caltech and a lot of helpful discussions. The authors are indebted to Natascha Junker, Bernhard\u2005E.\u2005C. Bugenhagen, and especially Prof. Peter Burger for help with the DFT calculations and generous computation time on the IAAC cluster at the University of Hamburg.\n\nSupplemental Material - chem201600679-sup-0001-misc_information.pdf
", "abstract": "A set of pyridine monoimine (PMI) rhenium(I) tricarbonyl chlorido complexes with substituents of different steric and electronic properties was synthesized and fully characterized. Spectroscopic (NMR and IR) and single-crystal X-ray diffraction analyses of these complexes showed that the redox-active PMI ligands are neutral and that the overall electronic structure is little affected by the choices of the substituent at the ligand backbone. One- and two-electron reduction products were prepared from selected starting compounds and could also be characterized by multiple spectroscopic methods and X-ray diffraction. The final product of a one-electron reduction in THF is a diamagnetic metal\u2013metal-bonded dimer after loss of the chlorido ligand. Bond lengths in and NMR chemical shifts of the PMI ligand backbone indicate partial electron transfer to the ligand. Two-electron reduction in THF also leads to the loss of the chlorido ligand and a pentacoordinate complex is obtained. The comparison with reported bond lengths and ^(13)C\u2005NMR chemical shifts of doubly reduced free pyridine monoaldimine ligands indicates that both redox equivalents in the doubly reduced rhenium complex investigated here are located in the PMI ligand. With diamagnetic complexes varying over three formal reduction stages at the PMI ligand we were, for the first time, able to establish correlations of the ^(13)C\u2005NMR chemical shifts with the relevant bond lengths in redox-active ligands over a full redox series.", "date": "2016-07-18", "date_type": "published", "publication": "Chemistry: a European Journal", "volume": "22", "number": "30", "publisher": "John Wiley & Sons", "pagerange": "10638-10650", "id_number": "CaltechAUTHORS:20160627-120321347", "issn": "0947-6539", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-120321347", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/chem.201600679", "primary_object": { "basename": "chem201600679-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/x8dmd-9mc82/files/chem201600679-sup-0001-misc_information.pdf" }, "pub_year": "2016", "author_list": "Sieh, Daniel and Kubiak, Clifford P." }, { "id": "https://authors.library.caltech.edu/records/9ja9f-tcy75", "eprint_id": 81739, "eprint_status": "archive", "datestamp": "2023-08-20 12:50:59", "lastmod": "2023-10-17 21:18:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kiriya-Daisuke", "name": { "family": "Kiriya", "given": "Daisuke" }, "orcid": "0000-0003-0270-3888" }, { "id": "Lobaccaro-P", "name": { "family": "Lobaccaro", "given": "Peter" } }, { "id": "Nyein-Hnin-Yin-Yin", "name": { "family": "Nyein", "given": "Hnin Yin Yin" } }, { "id": "Taheri-Peyman", "name": { "family": "Taheri", "given": "Peyman" } }, { "id": "Hettick-M", "name": { "family": "Hettick", "given": "Mark" } }, { "id": "Shiraki-Hiroshi", "name": { "family": "Shiraki", "given": "Hiroshi" } }, { "id": "Sutter-Fella-C-M", "name": { "family": "Sutter-Fella", "given": "Carolin M." } }, { "id": "Zhao-Peida", "name": { "family": "Zhao", "given": "Peida" } }, { "id": "Gao-Wei", "name": { "family": "Gao", "given": "Wei" }, "orcid": "0000-0002-8503-4562" }, { "id": "Maboudian-R", "name": { "family": "Maboudian", "given": "Roya" }, "orcid": "0000-0002-5121-6560" }, { "id": "Ager-J-W", "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" }, { "id": "Javey-A", "name": { "family": "Javey", "given": "Ali" }, "orcid": "0000-0001-7214-7931" } ] }, "title": "General Thermal Texturization Process of MoS_2 for Efficient Electrocatalytic Hydrogen Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived 9 February 2016. Published online 20 June 2016. Published in print 13 July 2016. \n\nXPS, SEM, XRD, and the final electrochemical characterization work was performed in collaboration with the Joint Center for Artificial Photosynthesis (JCAP), a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Processing and initial electrochemical characterization were performed in the Electronic Materials Program, which is supported by Director, Office of Science, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. TEM work was performed in collaboration with Mary Scott at the Molecular Foundry, which is supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.\n\nSupplemental Material - nl6b00569_si_001.pdf
", "abstract": "Molybdenum disulfide (MoS_2) has been widely examined as a catalyst containing no precious metals for the hydrogen evolution reaction (HER); however, these examinations have utilized synthesized MoS_2 because the pristine MoS_2 mineral is known to be a poor catalyst. The fundamental challenge with pristine MoS_2 is the inert HER activity of the predominant (0001) basal surface plane. In order to achieve high HER performance with pristine MoS_2, it is essential to activate the basal plane. Here, we report a general thermal process in which the basal plane is texturized to increase the density of HER-active edge sites. This texturization is achieved through a simple thermal annealing procedure in a hydrogen environment, removing sulfur from the MoS_2 surface to form edge sites. As a result, the process generates high HER catalytic performance in pristine MoS_2 across various morphologies such as the bulk mineral, films composed of micron-scale flakes, and even films of a commercially available spray of nanoflake MoS_2. The lowest overpotential (\u03b7) observed for these samples was \u03b7 = 170 mV to obtain 10 mA/cm_2 of HER current density.", "date": "2016-07-13", "date_type": "published", "publication": "Nano Letters", "volume": "16", "number": "7", "publisher": "American Chemical Society", "pagerange": "4047-4053", "id_number": "CaltechAUTHORS:20170922-093800265", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20170922-093800265", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.6b00569", "primary_object": { "basename": "nl6b00569_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9ja9f-tcy75/files/nl6b00569_si_001.pdf" }, "pub_year": "2016", "author_list": "Kiriya, Daisuke; Lobaccaro, Peter; et el." }, { "id": "https://authors.library.caltech.edu/records/7rmwj-97194", "eprint_id": 67806, "eprint_status": "archive", "datestamp": "2023-08-20 12:47:16", "lastmod": "2023-10-18 21:46:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Chuyang", "name": { "family": "Cheng", "given": "Chuyang" }, "orcid": "0000-0002-3834-0479" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Krzyaniak-M-D", "name": { "family": "Krzyaniak", "given": "Matthew D." }, "orcid": "0000-0002-8761-7323" }, { "id": "Wang-Yuping", "name": { "family": "Wang", "given": "Yuping" }, "orcid": "0000-0002-9315-2358" }, { "id": "McGonigal-P-R", "name": { "family": "McGonigal", "given": "Paul R." }, "orcid": "0000-0002-8538-7579" }, { "id": "Frasconi-M", "name": { "family": "Frasconi", "given": "Marco" }, "orcid": "0000-0003-2010-175X" }, { "id": "Barnes-J-C", "name": { "family": "Barnes", "given": "Jonathan C." } }, { "id": "Fahrenbach-A-C", "name": { "family": "Fahrenbach", "given": "Albert C." } }, { "id": "Wasielewski-M-R", "name": { "family": "Wasielewski", "given": "Michael R." }, "orcid": "0000-0003-2920-5440" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Stoddart-J-F", "name": { "family": "Stoddart", "given": "J. Fraser" }, "orcid": "0000-0003-3161-3697" } ] }, "title": "Influence of Constitution and Charge on Radical Pairing Interactions in Tris-radical Tricationic Complexes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes.\n\nReceived: May 5, 2016; Published: June 6, 2016.\n\nThis research is supported by National Science Foundation\n(NSF) under grant no. CHE-1308107. T.C., H.X., and W.A.G.\nthank the Joint Center for Artificial Photosynthesis, a DOE\nEnergy Innovation Hub, supported through the Office of\nScience of the U.S. Department of Energy under Award DESC0004993.\nThis work was also supported by the NSF under\ngrant no. CHE-1565925 (M.R.W.). The authors acknowledge\nthe Integrated Molecular Structure Education and Research\nCenter (IMSERC) at Northwestern University for NMR and\nHRMS characterizations. We thank Dr. Amy Sarjeant and\nCharlotte C. Stern for solving the single-crystal X-ray\nstructures. C.C. thanks the Chinese Scholarship Council for\nthe Award for Outstanding Self-Financed Students Abroad and\nForesight Institute for the Distinguished Student Award. A.C.F.\nacknowledges support from the Earth-Life Science Institute.\nJ.C.B. acknowledges postdoctoral support from the Howard\nHughes Medical Institute through the Life Sciences Research\nFoundation.\n\nPublished - jacsCHENGet_al.pdf
Supplemental Material - ja6b04343_si_001.pdf
Supplemental Material - ja6b04343_si_002.cif
Supplemental Material - ja6b04343_si_003.cif
Supplemental Material - ja6b04343_si_004.cif
Supplemental Material - ja6b04343_si_005.cif
Supplemental Material - ja6b04343_si_006.cif
Supplemental Material - ja6b04343_si_007.cif
", "abstract": "The results of a systematic investigation of trisradical tricationic complexes formed between cyclobis(paraquat-p-phenylene) bisradical dicationic (CBPQT2(\u2022+)) rings and a series of 18 dumbbells, containing centrally located 4,4\u2032-bipyridinium radical cationic (BIPY\u2022+) units within oligomethylene chains terminated for the most part by charged 3,5-dimethylpyridinium (PY+) and/or neutral 3,5-dimethylphenyl (PH) groups, are reported. The complexes were obtained by treating equimolar amounts of the CBPQT4+ ring and the dumbbells containing BIPY2+ units with zinc dust in acetonitrile (MeCN) solutions. Whereas UV-VIS-NIR spectra revealed absorption bands centered on ca. 1100 nm with quite different intensities for the 1:1 complexes depending on the constitutions and charges on the dumbbells, titration experiments show that the association constants (Ka) for complex formation vary over a wide range from Ka values of 800 M^(-1) for the weakest to 180000 M^(-1) for the strongest. While Coulombic repulsions emanating from PY+ groups located at the ends of some of the dumbbells undoubtedly contribute to the destabilization of the trisradical tricationic complexes, solid-state superstructures support the contention that those dumbbells with neutral PH groups at the ends of flexible and appropriately constituted links to the BIPY\u2022+ units stand to gain some additional stabilization from C\u2012H\u00b7\u00b7\u00b7\u03c0 interactions between the CBPQT2(\u2022+) rings and the PH termini on the dumbbells. The findings reported in this full paper demonstrate how structural changes implemented remotely from the BIPY\u2022+ units influence their noncovalent bonding interactions with CBPQT2(\u2022+) rings. Different secondary effects (Coulombic repulsions versus C\u2012H\u00b7\u00b7\u00b7\u03c0 interactions) are uncovered and their contributions to both binding strengths associated with trisradical interactions and the kinetics of associations and dissociations are discussed at some length and are supported by extensive DFT calculations at the M06-D3 level. A fundamental understanding of molecular recognition in radical complexes has relevance when it comes to the design and synthesis of non-equilibrium systems.", "date": "2016-07-06", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "26", "publisher": "American Chemical Society", "pagerange": "8288-8300", "id_number": "CaltechAUTHORS:20160610-073334314", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160610-073334314", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1308107" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-1565925" }, { "agency": "Chinese Scholarship Council" }, { "agency": "Foresight Institute" }, { "agency": "Earth-Life Science Institute" }, { "agency": "Howard Hughes Medical Institute (HHMI)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.6b04343", "primary_object": { "basename": "ja6b04343_si_002.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_002.cif" }, "related_objects": [ { "basename": "ja6b04343_si_003.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_003.cif" }, { "basename": "ja6b04343_si_004.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_004.cif" }, { "basename": "ja6b04343_si_005.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_005.cif" }, { "basename": "ja6b04343_si_006.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_006.cif" }, { "basename": "ja6b04343_si_007.cif", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_007.cif" }, { "basename": "jacsCHENGet_al.pdf", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/jacsCHENGet_al.pdf" }, { "basename": "ja6b04343_si_001.pdf", "url": "https://authors.library.caltech.edu/records/7rmwj-97194/files/ja6b04343_si_001.pdf" } ], "pub_year": "2016", "author_list": "Cheng, Chuyang; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/6p4gf-1f651", "eprint_id": 66588, "eprint_status": "archive", "datestamp": "2023-08-20 12:46:55", "lastmod": "2023-10-18 18:36:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "A Stabilized, Intrinsically Safe, 10% Efficient, Solar-Driven Water-Splitting Cell Incorporating Earth-Abundant Electrocatalysts with Steady-State pH Gradients and Product Separation Enabled by a Bipolar Membrane", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: February 21, 2016; Revised: March 19, 2016; Published online: First published: 29 April 2016. \n\nThe authors declare no competing financial interests. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993, as well as grant number 1225 from the Gordon and Betty Moore Foundation. The authors also thank N. Dalleska (Caltech) for his assistance with measurements and analysis of the ICPMS data. The authors also thank S. Lu, K. Walczak for gas-crossover measurements, R.J.R. Jones for designing the flow-cell reactor, X. Zhou for preparation of the ALD TiO_2 coatings, and J. C. Crompton for preparation of the CoP-coated metal meshes.\n\nSupplemental Material - aenm201600379-sup-0001-S1.pdf
", "abstract": "An efficient, stable, and intrinsically safe solar water-splitting device is demonstrated using a III\u2013V tandem junction photoanode, an acid-stable, earth-abundant hydrogen evolution catalyst, and a bipolar membrane. The integrated photoelectrochemical cell operates under a steady-state pH gradient and achieves \u224810% solar-to-hydrogen conversion efficiency, >100 h of stability in a large (>1 cm^2) photoactive area in relation to most previous reports.", "date": "2016-07-06", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "6", "number": "13", "publisher": "Wiley", "pagerange": "Art. No. 1600379", "id_number": "CaltechAUTHORS:20160502-135457387", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160502-135457387", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201600379", "primary_object": { "basename": "aenm201600379-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/6p4gf-1f651/files/aenm201600379-sup-0001-S1.pdf" }, "pub_year": "2016", "author_list": "Sun, Ke; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/a0pe1-p7f58", "eprint_id": 69089, "eprint_status": "archive", "datestamp": "2023-08-20 12:46:38", "lastmod": "2023-10-20 16:31:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "Francesca M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Cooper-Jason-K", "name": { "family": "Cooper", "given": "Jason K." }, "orcid": "0000-0002-7953-4229" }, { "id": "Kunzelmann-Viktoria", "name": { "family": "Kunzelmann", "given": "Viktoria" }, "orcid": "0000-0002-4225-0476" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Larson-David-M", "name": { "family": "Larson", "given": "David M." }, "orcid": "0000-0001-9634-9175" }, { "id": "Borys-Nicholas-J", "name": { "family": "Borys", "given": "Nicholas J." }, "orcid": "0000-0001-5434-1191" }, { "id": "Abelyan-Christine", "name": { "family": "Abelyan", "given": "Christine" } }, { "id": "Beeman-Jeffrey-W", "name": { "family": "Beeman", "given": "Jeffrey W." }, "orcid": "0000-0002-5678-6255" }, { "id": "Yu-Kin-Man", "name": { "family": "Yu", "given": "Kin Man" } }, { "id": "Yang-Jinhui", "name": { "family": "Yang", "given": "Jinhui" } }, { "id": "Chen-Le", "name": { "family": "Chen", "given": "Le" } }, { "id": "Shaner-Matthew-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Spurgeon-Joshua-M", "name": { "family": "Spurgeon", "given": "Joshua" }, "orcid": "0000-0002-2987-0865" }, { "id": "Houle-Frances-A", "name": { "family": "Houle", "given": "Frances A." }, "orcid": "0000-0001-5571-2548" }, { "id": "Persson-Kristin-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" } ] }, "title": "Mechanistic insights into chemical and photochemical transformations of bismuth vanadate photoanodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Macmillan Publishers Limited.\n\nThis work is licensed under a Creative Commons Attribution 4.0\nInternational License. The images or other third party material in this\narticle are included in the article's Creative Commons license, unless indicated otherwise\nin the credit line; if the material is not included under the Creative Commons license,\nusers will need to obtain permission from the license holder to reproduce the material.\nTo view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.\n\nReceived 01 January 2016; Accepted 20 May 2016; Published 05 July 2016.\n\nThis study is based on work performed at the Joint Center for Artificial Photosynthesis, a\nDOE Energy Innovation Hub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993. Imaging work\nat the Molecular Foundry was supported by the Office of Science, Office of\nBasic Energy Sciences, of the U.S. Department of Energy under contract number\nDE-AC02-05CH11231. The EC-AFM part of this work was supported in part by the\nLaboratory Directed Research and Development Program of Lawrence Berkeley National\nLaboratory under U.S. Department of Energy contract number DE-AC02-05CH11231.\nV.K. and F.M.T. acknowledge support from the BaCaTeC programme, project number\n2015-1. Craig Jones from Agilent Technologies, Inc. is greatly acknowledged for his help\nwith ICP-MS measurements.\n\nAuthor contributions:\nF.M.T., F.A.H. and I.D.S. conceived of and designed this study. F.M.T., J.K.C., V.K.,\nM.T.M., D.L., C.A., J.W.B. and I.D.S. performed the experiments. F.M.T., J.K.C., N.J.B.,\nK.M.Y., J. Yang, F.A.H. and I.D.S. analysed and interpreted the data. J. Yu and K.A.P.\nperformed the theoretical calculations and associated analysis. L.C., M.R.S. and J.S.\nprovided some of the materials used for preliminary testing. All authors contributed to\nthe final version of the manuscript.\n\nCompeting financial interests: The authors declare no competing financial interests.\n\nPublished - ncomms12012.pdf
Supplemental Material - ncomms12012-s1.pdf
Supplemental Material - ncomms12012-s2.avi
Supplemental Material - ncomms12012-s3.zip
", "abstract": "Artificial photosynthesis relies on the availability of semiconductors that are chemically stable and can efficiently capture solar energy. Although metal oxide semiconductors have been investigated for their promise to resist oxidative attack, materials in this class can suffer from chemical and photochemical instability. Here we present a methodology for evaluating corrosion mechanisms and apply it to bismuth vanadate, a state-of-the-art photoanode. Analysis of changing morphology and composition under solar water splitting conditions reveals chemical instabilities that are not predicted from thermodynamic considerations of stable solid oxide phases, as represented by the Pourbaix diagram for the system. Computational modelling indicates that photoexcited charge carriers accumulated at the surface destabilize the lattice, and that self-passivation by formation of a chemically stable surface phase is kinetically hindered. Although chemical stability of metal oxides cannot be assumed, insight into corrosion mechanisms aids development of protection strategies and discovery of semiconductors with improved stability.", "date": "2016-07-05", "date_type": "published", "publication": "Nature Communications", "volume": "7", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 12012", "id_number": "CaltechAUTHORS:20160718-095141596", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160718-095141596", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "BaCaTeC programme", "grant_number": "2015-1" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/ncomms12012", "pmcid": "PMC4935965", "primary_object": { "basename": "ncomms12012-s1.pdf", "url": "https://authors.library.caltech.edu/records/a0pe1-p7f58/files/ncomms12012-s1.pdf" }, "related_objects": [ { "basename": "ncomms12012-s2.avi", "url": "https://authors.library.caltech.edu/records/a0pe1-p7f58/files/ncomms12012-s2.avi" }, { "basename": "ncomms12012-s3.zip", "url": "https://authors.library.caltech.edu/records/a0pe1-p7f58/files/ncomms12012-s3.zip" }, { "basename": "ncomms12012.pdf", "url": "https://authors.library.caltech.edu/records/a0pe1-p7f58/files/ncomms12012.pdf" } ], "pub_year": "2016", "author_list": "Toma, Francesca M.; Cooper, Jason K.; et el." }, { "id": "https://authors.library.caltech.edu/records/vx6tx-dsv97", "eprint_id": 67844, "eprint_status": "archive", "datestamp": "2023-08-20 12:45:22", "lastmod": "2023-10-18 21:48:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "McFarland-E-W", "name": { "family": "McFarland", "given": "Eric W." } } ] }, "title": "A comparative technoeconomic analysis of renewable hydrogen production using solar energy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Royal Society of Chemistry. \n\nReceived 19 Aug 2015, Accepted 05 May 2016, First published online 26 May 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Support for this technoeconomic analysis was provided jointly by the Dow Centre for Sustainable Engineering Innovation at the University of Queensland, and the Resnick Institute for Sustainability at Caltech.\n\nPublished - c5ee02573g.pdf
Supplemental Material - c5ee02573g1.pdf
", "abstract": "A technoeconomic analysis of photoelectrochemical (PEC) and photovoltaic-electrolytic (PV-E) solar-hydrogen production of 10 000 kg H_2 day^(\u22121) (3.65 kilotons per year) was performed to assess the economics of each technology, and to provide a basis for comparison between these technologies as well as within the broader energy landscape. Two PEC systems, differentiated primarily by the extent of solar concentration (unconcentrated and 10\u00d7 concentrated) and two PV-E systems, differentiated by the degree of grid connectivity (unconnected and grid supplemented), were analyzed. In each case, a base-case system that used established designs and materials was compared to prospective systems that might be envisioned and developed in the future with the goal of achieving substantially lower overall system costs. With identical overall plant efficiencies of 9.8%, the unconcentrated PEC and non-grid connected PV-E system base-case capital expenses for the rated capacity of 3.65 kilotons H_2 per year were $205 MM ($293 per m^2 of solar collection area (m_S^(\u22122)), $14.7 W_(H2,P)^(\u22121)) and $260 MM ($371 m_S^(\u22122), $18.8 W_(H2,P)^(\u22121)), respectively. The untaxed, plant-gate levelized costs for the hydrogen product (LCH) were $11.4 kg^(\u22121) and $12.1 kg^(\u22121) for the base-case PEC and PV-E systems, respectively. The 10\u00d7 concentrated PEC base-case system capital cost was $160 MM ($428 m_S^(\u22122), $11.5 W_(H2,P)^(\u22121)) and for an efficiency of 20% the LCH was $9.2 kg^(\u22121). Likewise, the grid supplemented base-case PV-E system capital cost was $66 MM ($441 m_S^(\u22122), $11.5 W_(H2,P)^(\u22121)), and with solar-to-hydrogen and grid electrolysis system efficiencies of 9.8% and 61%, respectively, the LCH was $6.1 kg^(\u22121). As a benchmark, a proton-exchange membrane (PEM) based grid-connected electrolysis system was analyzed. Assuming a system efficiency of 61% and a grid electricity cost of $0.07 kWh^(\u22121), the LCH was $5.5 kg^(\u22121). A sensitivity analysis indicated that, relative to the base-case, increases in the system efficiency could effect the greatest cost reductions for all systems, due to the areal dependencies of many of the components. The balance-of-systems (BoS) costs were the largest factor in differentiating the PEC and PV-E systems. No single or combination of technical advancements based on currently demonstrated technology can provide sufficient cost reductions to allow solar hydrogen to directly compete on a levelized cost basis with hydrogen produced from fossil energy. Specifically, a cost of CO_2 greater than \u223c$800 (ton CO_2)^(\u22121) was estimated to be necessary for base-case PEC hydrogen to reach price parity with hydrogen derived from steam reforming of methane priced at $12 GJ^(\u22121) ($1.39 (kg H_2)^(\u22121)). A comparison with low CO_2 and CO_2-neutral energy sources indicated that base-case PEC hydrogen is not currently cost-competitive with electrolysis using electricity supplied by nuclear power or from fossil-fuels in conjunction with carbon capture and storage. Solar electricity production and storage using either batteries or PEC hydrogen technologies are currently an order of magnitude greater in cost than electricity prices with no clear advantage to either battery or hydrogen storage as of yet. Significant advances in PEC technology performance and system cost reductions are necessary to enable cost-effective PEC-derived solar hydrogen for use in scalable grid-storage applications as well as for use as a chemical feedstock precursor to CO_2-neutral high energy-density transportation fuels. Hence such applications are an opportunity for foundational research to contribute to the development of disruptive approaches to solar fuels generation systems that can offer higher performance at much lower cost than is provided by current embodiments of solar fuels generators. Efforts to directly reduce CO_2 photoelectrochemically or electrochemically could potentially produce products with higher value than hydrogen, but many, as yet unmet, challenges include catalytic efficiency and selectivity, and CO_2 mass transport rates and feedstock cost. Major breakthroughs are required to obtain viable economic costs for solar hydrogen production, but the barriers to achieve cost-competitiveness with existing large-scale thermochemical processes for CO_2 reduction are even greater.", "date": "2016-07-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "7", "publisher": "Royal Society of Chemistry", "pagerange": "2354-2371", "id_number": "CaltechAUTHORS:20160610-132918453", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160610-132918453", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of Queensland" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c5ee02573g", "primary_object": { "basename": "c5ee02573g.pdf", "url": "https://authors.library.caltech.edu/records/vx6tx-dsv97/files/c5ee02573g.pdf" }, "related_objects": [ { "basename": "c5ee02573g1.pdf", "url": "https://authors.library.caltech.edu/records/vx6tx-dsv97/files/c5ee02573g1.pdf" } ], "pub_year": "2016", "author_list": "Shaner, Matthew R.; Atwater, Harry A.; et el." }, { "id": "https://authors.library.caltech.edu/records/5kpb8-3fp54", "eprint_id": 68687, "eprint_status": "archive", "datestamp": "2023-08-21 17:42:08", "lastmod": "2023-10-19 23:16:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Aspects of science and technology in support of legal and policy frameworks associated with a global carbon emissions-control regime", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Royal Society of Chemistry. \n\nReceived 27th January 2016, Accepted 2nd June 2016, First published online 02 Jun 2016. \n\nI acknowledge the Department of Energy and the National Science Foundation for sustained support that made the preparation of this piece possible.\n\nPublished - c6ee00272b.pdf
", "abstract": "The delegates to COP21 in Paris, in conjunction with nationally formulated commitments and pledges, resolved that countries should take actions to \"hold the increase in global temperature to well below 2 \u00b0C above pre-industrial levels\" and to achieve \"a balance between anthropogenic emissions by sources and removal by sinks of greenhouse gases in the second half of this century\". This resolution for action suggests a step towards a global carbon emissions-control regime which, due to regional variabilities and remaining uncertainties as to the exact effects of atmospheric CO_2 concentrations, must be considered within the purview of risk management. In this Opinion, four topics are discussed that intertwine science, technology, legal, and policy issues critical to the implementation of any global carbon emissions-control regime: (i) What to regulate and at what levels; (ii) Regulating short-term versus long-term emissions; (iii) Validation of compliance in a regulated global emissions regime; and, (iv) Legal aspects of geoengineering.", "date": "2016-07-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "7", "publisher": "Royal Society of Chemistry", "pagerange": "2172-2176", "id_number": "CaltechAUTHORS:20160627-113518244", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-113518244", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)" }, { "agency": "NSF" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c6ee00272b", "primary_object": { "basename": "c6ee00272b.pdf", "url": "https://authors.library.caltech.edu/records/5kpb8-3fp54/files/c6ee00272b.pdf" }, "pub_year": "2016", "author_list": "Lewis, Nathan S." }, { "id": "https://authors.library.caltech.edu/records/yrxca-a0n49", "eprint_id": 68751, "eprint_status": "archive", "datestamp": "2023-08-20 12:33:35", "lastmod": "2023-10-19 23:36:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bernardi-Marco", "name": { "family": "Bernardi", "given": "Marco" }, "orcid": "0000-0001-7289-9666" }, { "id": "Grossman-J-C", "name": { "family": "Grossman", "given": "Jeffrey C." }, "orcid": "0000-0003-1281-2359" } ] }, "title": "Computer calculations across time and length scales in photovoltaic solar cells", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 06 Apr 2016, Accepted 05 May 2016, First published online 05 May 2016. \n\nMB thanks the California Institute of Technology for start-up funds and NERSC for computational resources. MB acknowledges partial support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the development of part of this review article was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. JCG is grateful for support from the Eni Solar Frontiers Program at MIT.\n\nPublished - c6ee01010e.pdf
", "abstract": "Photovoltaic (PV) solar cells convert solar energy to electricity through a cascade of microscopic processes spanning over 10 order of magnitudes of time and length. PV conversion involves a complex interplay of photons, charge carriers, and excited states. Processes following light absorption include generation of charge carriers or excitons, exciton dissociation over nanometer lengths and subpicosecond times, and carrier transport over ns\u2013ms times and nm\u2013mm lengths. Computer calculations have become an indispensable tool to understand and engineer solar cells across length and time scales. In this article, we examine the microscopic processes underlying PV conversion and review state-of-the-art computational methods to study PV solar cells. Recent developments and future research challenges are outlined.", "date": "2016-07", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "7", "publisher": "Royal Society of Chemistry", "pagerange": "2197-2218", "id_number": "CaltechAUTHORS:20160629-122500821", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160629-122500821", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Massachusetts Institute of Technology (MIT)" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C6EE01010E", "primary_object": { "basename": "c6ee01010e.pdf", "url": "https://authors.library.caltech.edu/records/yrxca-a0n49/files/c6ee01010e.pdf" }, "pub_year": "2016", "author_list": "Bernardi, Marco and Grossman, Jeffrey C." }, { "id": "https://authors.library.caltech.edu/records/sxfbh-n8y34", "eprint_id": 68758, "eprint_status": "archive", "datestamp": "2023-08-20 12:30:18", "lastmod": "2023-10-20 15:41:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Xiaogang", "name": { "family": "Yang", "given": "Xiaogang" }, "orcid": "0000-0002-1142-3100" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Lei-Yan", "name": { "family": "Lei", "given": "Yan" }, "orcid": "0000-0003-2906-0050" }, { "id": "Li-Pinjiang", "name": { "family": "Li", "given": "Pinjiang" } }, { "id": "Wang-Ke", "name": { "family": "Wang", "given": "Ke" } }, { "id": "Zheng-Zhi", "name": { "family": "Zheng", "given": "Zhi" }, "orcid": "0000-0002-5889-4305" }, { "id": "Wang-Dunwei", "name": { "family": "Wang", "given": "Dunwei" } } ] }, "title": "Dual Influence of Reduction Annealing on Diffused Hematite/FTO Junction for Enhanced Photoelectrochemical Water Oxidation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "diffused junction, hematite/FTO interface, reduction-annealing activation, transient surface photovoltage,\nnanoelectric conductivity", "note": "\u00a9 2016 American Chemical Society\n\nReceived: April 8, 2016\nAccepted: June 8, 2016\nPublished: June 8, 2016\n\nWe thank Prof. Dejun Wang from Jilin University for his help with the TSPV instrument. X.Y. and P.L. were supported by the grant from the Henan Province Office of Education (14B150013) and Henan Province of International Science & Technology Cooperation (134300510061). Z.Z. was supported by the grant from the National Natural Science Foundation of China (21273192), Program for Innovative Research Team, University of Henan Province (2012IRTSTHN021) and Innovation Scientists and Technicians Troop Construction Projects of Henan Province (144200510014). R.L. is supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science, U.S. Department of Energy, under Award Number DE-SC0004993. XPS studies were carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. D.W. was supported by the National Science Foundation (DMR 1055762).", "abstract": "Band structure engineering of the interface between the semiconductor and the conductive substrate may profoundly influence charge separation and transport for photovoltaic and photoelectrochemical devices. In this work, we found that a reduction-annealing treatment resulted in a diffused junction through enhanced interdiffusion of hematite/FTO at the interface. The activated hematite exhibited higher nanoelectric conductivity that was probed by a PeakForce TUNA AFM method. Furthermore, charge accumulation and recombination via surface states at the interface were dramatically reduced after the reduction-annealing activation, which was confirmed by transient surface photovoltage measurements. The diffused hematite junction promises improved photoelectrochemical performance without the need for a buffer layer.", "date": "2016-06-29", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "8", "number": "25", "publisher": "American Chemical Society", "pagerange": "16476-16485", "id_number": "CaltechAUTHORS:20160629-132009561", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160629-132009561", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Henan Province Office of Education", "grant_number": "14B150013" }, { "agency": "Henan Province of International Science & Technology Cooperation", "grant_number": "134300510061" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21273192" }, { "agency": "Program for Innovative Research Team, University of Henan Province", "grant_number": "2012IRTSTHN021" }, { "agency": "Innovation Scientists and Technicians Troop Construction Projects of Henan Province", "grant_number": "144200510014" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "NSF", "grant_number": "DMR 1055762" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.6b04213", "pub_year": "2016", "author_list": "Yang, Xiaogang; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/91h5j-tde46", "eprint_id": 67847, "eprint_status": "archive", "datestamp": "2023-08-20 12:29:45", "lastmod": "2023-10-18 21:48:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Schwarz-K", "name": { "family": "Schwarz", "given": "Kathleen" } }, { "id": "Xu-Bingjun", "name": { "family": "Xu", "given": "Bingjun" }, "orcid": "0000-0002-2303-257X" }, { "id": "Yan-Yushan", "name": { "family": "Yan", "given": "Yushan" } }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" } ] }, "title": "Partial oxidation of step-bound water leads to anomalous pH effects on metal electrode step-edges", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 the Owner Societies. \n\nReceived 10th March 2016, Accepted 26th May 2016, First published online 26 May 2016. \n\nKAS thanks T. P. Moffat for helpful discussions. RS was supported by the Joint Center of Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.", "abstract": "The design of better heterogeneous catalysts for applications such as fuel cells and electrolyzers requires a mechanistic understanding of electrocatalytic reactions and the dependence of their activity on operating conditions such as pH. A satisfactory explanation for the unexpected pH dependence of electrochemical properties of platinum surfaces has so far remained elusive, with previous explanations resorting to complex co-adsorption of multiple species and resulting in limited predictive power. This knowledge gap suggests that the fundamental properties of these catalysts are not yet understood, limiting systematic improvement. Here, we analyze the change in charge and free energies upon adsorption using density-functional theory (DFT) to establish that water adsorbs on platinum step edges across a wide voltage range, including the double-layer region, with a loss of approximately 0.2 electrons upon adsorption. We show how this as-yet unreported change in net surface charge due to this water explains the anomalous pH variations of the hydrogen underpotential deposition (H_(upd)) and the potentials of zero total charge (PZTC) observed in published experimental data. This partial oxidation of water is not limited to platinum metal step edges, and we report the charge of the water on metal step edges of commonly used catalytic metals, including copper, silver, iridium, and palladium, illustrating that this partial oxidation of water broadly influences the reactivity of metal electrodes.", "date": "2016-06-28", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "18", "number": "24", "publisher": "Royal Society of Chemistry", "pagerange": "16216-16223", "id_number": "CaltechAUTHORS:20160610-140536521", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160610-140536521", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c6cp01652a", "pub_year": "2016", "author_list": "Schwarz, Kathleen; Xu, Bingjun; et el." }, { "id": "https://authors.library.caltech.edu/records/s88pb-v4372", "eprint_id": 68693, "eprint_status": "archive", "datestamp": "2023-09-15 05:28:26", "lastmod": "2023-10-23 21:17:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Modeling and Simulation of the Spatial and Light-Intensity Dependence of Product Distributions in an Integrated Photoelectrochemical CO_2 Reduction System", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: May 10, 2016\nAccepted: June 8, 2016. \n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993.", "abstract": "A multiphysics model that accounts for the performance of electrocatalysts and triple-junction light absorbers, as well as for the transport properties of the electrolyte and dissolved CO_2, was used to evaluate the spatial and light-intensity dependence of product distributions in an integrated photoelectrochemical CO2 reduction (CO_2R) cell. Different sets of band gap combinations of triple-junction light absorbers were required to accommodate the optimal total operating current density relative to the optimal partial current density for CO_2R. The simulated product distribution was highly nonuniform along the width of the electrode and depended on the electrode dimensions as well as the illumination intensity. To achieve the same product selectivity as in a potentiostatic, \"half-cell\" configuration, the electrocatalyst must retain its selectivity over a range of cathode potentials, and this range is dependent on the transport losses and current\u2013voltage relationship of the light absorbers, the geometric parameters of the cell, and the illumination intensity.", "date": "2016-06-08", "date_type": "published", "publication": "ACS Energy Letters", "volume": "2016", "number": "1", "publisher": "American Chemical Society", "pagerange": "273-280", "id_number": "CaltechAUTHORS:20160627-135527397", "issn": "2380-8195", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-135527397", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsenergylett.6b00134", "pub_year": "2016", "author_list": "Chen, Yikai; Lewis, Nathan S.; et el." }, { "id": "https://authors.library.caltech.edu/records/w90d3-03159", "eprint_id": 68685, "eprint_status": "archive", "datestamp": "2023-08-20 11:50:39", "lastmod": "2023-10-19 23:11:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-Prineha", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Sundararaman-Ravishankar", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Plasmonic hot carrier dynamics in solid-state and chemical systems for energy conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Prineha Narang et al., published by De Gruyter Open.\nThis work is licensed under the Creative Commons Attribution-Non Commercial-No Derivs 3.0 License.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P. N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute.\n\nPublished - nanoph-2016-0007.pdf
", "abstract": "Surface plasmons provide a pathway to efficiently absorb and confine light in metallic nanostructures, thereby bridging photonics to the nano scale. The decay of surface plasmons generates energetic 'hot' carriers, which can drive chemical reactions or be injected into semiconductors for nano-scale photochemical or photovoltaic energy conversion. Novel plasmonic hot carrier devices and architectures continue to be demonstrated, but the complexity of the underlying processes make a complete microscopic understanding of all the mechanisms and design considerations for such devices extremely challenging.Here,we review the theoretical and computational efforts to understand and model plasmonic hot carrier devices.We split the problem into three steps: hot carrier generation, transport and collection, and review theoretical approaches with the appropriate level of detail for each step along with their predictions. We identify the key advances necessary to complete the microscopic mechanistic picture and facilitate the design of the next generation of devices and materials for plasmonic energy conversion.", "date": "2016-06", "date_type": "published", "publication": "Nanophotonics", "volume": "5", "number": "1", "publisher": "De Gruyter", "pagerange": "96-111", "id_number": "CaltechAUTHORS:20160627-104035060", "issn": "2192-8606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160627-104035060", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1515/nanoph-2016-0007", "primary_object": { "basename": "nanoph-2016-0007.pdf", "url": "https://authors.library.caltech.edu/records/w90d3-03159/files/nanoph-2016-0007.pdf" }, "pub_year": "2016", "author_list": "Narang, Prineha; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/9c7ee-3xa42", "eprint_id": 68732, "eprint_status": "archive", "datestamp": "2023-08-22 18:01:03", "lastmod": "2023-10-19 23:35:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Azarpia-A", "name": { "family": "Azarpia", "given": "Anahita" } }, { "id": "Schedel-Niedrig-T", "name": { "family": "Schedel-Niedrig", "given": "Thomas" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H.-J." }, "orcid": "0000-0001-8433-9471" }, { "id": "Lublow-M", "name": { "family": "Lublow", "given": "Michael" } } ] }, "title": "Sustained Water Oxidation by Direct Electrosynthesis of Ultrathin Organic Protection Films on Silicon", "ispublished": "pub", "full_text_status": "public", "keywords": "organic protection layer; oxygen evolution reaction; photoelectrocatalysis; RuO2; silicon supports", "note": "\u00a9 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim\n\nReceived: November 19, 2015\nRevised: January 17, 2016\nPublished online: March 11, 2016\n\nThe authors are thankful for fruitful discussion with R. van de Krol. They gratefully acknowledge the financial support provided by the Deutsche Forschungsgemeinschaft (DFG), project No. SCHE 533/3-1 within the priority program SPP 1613-\"Solar-H 2.\" M.L. acknowledges temporary financial support granted by Freiburg University, Germany (group A. Fischer). The joint discussion and interpretation of the data and contributions to the manuscript (H.J.L.) was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993.\n\nSupplemental Material - aenm201502314-sup-0001-S1.pdf_v=003d1_s=003dfd2f9977e539273d1ecfda6d8457737987ce87e2
Supplemental Material - aenm201502314-sup-0001-S1.pdf_v=1_s=fd2f9977e539273d1ecfda6d8457737987ce87e2
", "abstract": "Artificial photosynthesis allows exceeding the efficiency and stability limits of natural photosynthesis. Based on the use of semiconducting absorbers, high efficiency in water photolysis has been achieved in various photoelectrode configurations. However, integrated systems are limited in their stability, and more stable half-cell electrodes use protection films prepared by laborious methods. Herein, the facile low-temperature preparation of ultrathin organic protection coatings is demonstrated. The formation is based on the catalytic properties of water oxidation catalysts toward alcohol-polymerization reactions, which results in the formation of hitherto unknown protection layers on silicon. The interfacial layers are generated via iodine-mediated electro-reductive polymerization of ethanol, concomitantly forming during electrophoretic transport of RuO_2 onto silicon supports. Reaction chemistry analyses show that the RuO_2-induced catalysis introduces E2-elimination reactions which result in a carbon sp^3 \u2013sp^2 transformation of the film. For the two modes of photoelectrochemical operation, the photovoltaic and the photoelectrocatalytic mode, 20 and 15 mA cm^(\u22122) photocurrent densities, respectively, are obtained with unaltered output for 8 and 24 h. The interfacial layer enables Si photovoltages of 500 mV, demonstrating extraordinary electronic interface quality. Since only hydrogen termination of the surface is a prerequisite for growth of the organic protection layer, the method is applicable to a wide range of semiconductors.", "date": "2016-05-25", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "6", "number": "10", "publisher": "Wiley", "pagerange": "1502314", "id_number": "CaltechAUTHORS:20160629-084424702", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160629-084424702", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "SCHE 533/3-1" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "SPP 1613-\"Solar-H_2\"" }, { "agency": "Freiburg University" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201502314", "primary_object": { "basename": "aenm201502314-sup-0001-S1.pdf_v=003d1_s=003dfd2f9977e539273d1ecfda6d8457737987ce87e2", "url": "https://authors.library.caltech.edu/records/9c7ee-3xa42/files/aenm201502314-sup-0001-S1.pdf_v=003d1_s=003dfd2f9977e539273d1ecfda6d8457737987ce87e2" }, "pub_year": "2016", "author_list": "Azarpia, Anahita; Schedel-Niedrig, Thomas; et el." }, { "id": "https://authors.library.caltech.edu/records/d2wax-wyv12", "eprint_id": 66511, "eprint_status": "archive", "datestamp": "2023-08-20 11:43:08", "lastmod": "2023-10-18 18:09:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jiang-Shaojie", "name": { "family": "Jiang", "given": "Shaojie" } }, { "id": "Fang-Yanan", "name": { "family": "Fang", "given": "Yanan" } }, { "id": "Li-Ruipeng", "name": { "family": "Li", "given": "Ruipeng" } }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Crowley-J", "name": { "family": "Crowley", "given": "Jason" } }, { "id": "Wang-Chenyu", "name": { "family": "Wang", "given": "Chenyu" } }, { "id": "White-T-J", "name": { "family": "White", "given": "Timothy J." }, "orcid": "0000-0001-8006-7173" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Wang-Zhongwu", "name": { "family": "Wang", "given": "Zhongwu" } }, { "id": "Baikie-T", "name": { "family": "Baikie", "given": "Tom" } }, { "id": "Fang-Jiye", "name": { "family": "Fang", "given": "Jiye" } } ] }, "title": "Pressure-Dependent Polymorphism and Band-Gap Tuning of Methylammonium Lead Iodide Perovskite", "ispublished": "pub", "full_text_status": "public", "keywords": "band gap \u00b7 halide perovskite \u00b7\nhigh-pressure chemistry \u00b7 phase transitions \u00b7\nphotoluminescence", "note": "\u00a9 2016 Wiley-VCH Verlag GmbH & Co. Received: February 19, 2016. Article first published online: 21 Apr 2016.\n\nThis work is partially supported by NRF-CRP14-2014-03,\nCustom Electronics, Inc., and the Joint Center for Artificial\nPhotosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of\nEnergy under Award No. DE-SC0004993. CHESS is supported\nby the NSF award DMR-1332208. S.J. acknowledges\nthe support by Binghamton University.\n\nSupplemental Material - anie201601788-sup-0001-misc_information.pdf
", "abstract": "We report the pressure-induced crystallographic transitions and optical behavior of MAPbI_3 (MA=methylammonium) using in\u2005situ synchrotron X-ray diffraction and laser-excited photoluminescence spectroscopy, supported by density functional theory (DFT) calculations using the hybrid functional B3PW91 with spin-orbit coupling. The tetragonal polymorph determined at ambient pressure transforms to a ReO_3-type cubic phase at 0.3\u2005GPa. Upon continuous compression to 2.7\u2005GPa this cubic polymorph converts into a putative orthorhombic structure. Beyond 4.7\u2005GPa it separates into crystalline and amorphous fractions. During decompression, this phase-mixed material undergoes distinct restoration pathways depending on the peak pressure. In\u2005situ pressure photoluminescence investigation suggests a reduction in band gap with increasing pressure up to \u22480.3\u2005GPa and then an increase in band gap up to a pressure of 2.7\u2005GPa, in excellent agreement with our DFT calculation prediction.", "date": "2016-05-23", "date_type": "published", "publication": "Angewandte Chemie International Edition", "volume": "55", "number": "22", "publisher": "Wiley", "pagerange": "6540-6544", "id_number": "CaltechAUTHORS:20160427-103659758", "issn": "1433-7851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160427-103659758", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "National Research Foundation of Korea (NRF)", "grant_number": "NRF-CRP14-2014-03" }, { "agency": "Custom Electronics Inc." }, { "agency": "Joint Center for Artificial Photosynthesis" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1332208" }, { "agency": "Binghamton University" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/anie.201601788", "primary_object": { "basename": "anie201601788-sup-0001-misc_information.pdf", "url": "https://authors.library.caltech.edu/records/d2wax-wyv12/files/anie201601788-sup-0001-misc_information.pdf" }, "pub_year": "2016", "author_list": "Jiang, Shaojie; Fang, Yanan; et el." }, { "id": "https://authors.library.caltech.edu/records/b2hg6-vh603", "eprint_id": 66581, "eprint_status": "archive", "datestamp": "2023-08-20 11:42:11", "lastmod": "2023-10-18 18:36:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "P. F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Boyd-D-A", "name": { "family": "Boyd", "given": "D. A." } }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "A." }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "L." }, "orcid": "0000-0002-7052-266X" }, { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "E." } }, { "id": "Li-Guiji", "name": { "family": "Li", "given": "G." } }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "J. B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Solar fuel photoanodes prepared by inkjet printing of copper vanadates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 10 Feb 2016, Accepted 11 Apr 2016. First published online 11 Apr 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The authors thank Natalie Becerra-Stasiewicz for assistance with acquisition of the SEM images, Santosh Suram for assistance with UV-vis data, Joel Haber for helpful discussion and Florian Brown-Altvater for assistance with the Raman calculations.\n\nPublished - c6ta01252c.pdf
Supplemental Material - c6ta01252c1.pdf
Supplemental Material - c6ta01252c2.zip
", "abstract": "Widespread deployment of solar fuel generators requires the development of efficient and scalable functional materials, especially for photoelectrocatalysis of the oxygen evolution reaction. Metal oxides comprise the most promising class of photoanode materials, but no known material meets the demanding photoelectrochemical requirements. Copper vanadates have recently been identified as a promising class of photoanode materials with several phases exhibiting an indirect band gap near 2 eV and stable photoelectrocatalysis of the oxygen evolution reaction in a pH 9.2 electrolyte. By employing combinatorial inkjet printing of metal precursors and applying both calcination and rapid thermal processing, we characterize the phase behaviour of the entire CuO\u2013V_2O_5 composition space for different thermal treatments via automated analysis of approximately 100 000 Raman spectra acquired using a novel Raman imaging technique. These results enable the establishment of structure\u2013property relationships for optical absorption and photoelectrochemical properties, revealing that highly active photoelectrocatalysts containing \u03b1-Cu_2V_2O_7 or \u03b1-CuV_2O_6 can be prepared using scalable solution processing techniques. An additional discovery results from the formation of an off-stoichiometric \u03b2-Cu_2V_2O_7 material that exhibits high photoelectroactivity in the presence of a ferri/ferrocyanide redox couple with excellent stability in a pH 13 electrolyte, demonstrating that copper vanadates may be viable photoanodes in strong alkaline electrolytes.", "date": "2016-05-21", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "4", "number": "19", "publisher": "Royal Society of Chemistry", "pagerange": "7483-7494", "id_number": "CaltechAUTHORS:20160502-100311001", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160502-100311001", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C6TA01252C", "primary_object": { "basename": "c6ta01252c.pdf", "url": "https://authors.library.caltech.edu/records/b2hg6-vh603/files/c6ta01252c.pdf" }, "related_objects": [ { "basename": "c6ta01252c1.pdf", "url": "https://authors.library.caltech.edu/records/b2hg6-vh603/files/c6ta01252c1.pdf" }, { "basename": "c6ta01252c2.zip", "url": "https://authors.library.caltech.edu/records/b2hg6-vh603/files/c6ta01252c2.zip" } ], "pub_year": "2016", "author_list": "Newhouse, P. F.; Boyd, D. A.; et el." }, { "id": "https://authors.library.caltech.edu/records/xt843-srs47", "eprint_id": 66525, "eprint_status": "archive", "datestamp": "2023-08-20 11:38:24", "lastmod": "2023-10-18 18:10:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Yuanyue", "name": { "family": "Liu", "given": "Yuanyue" }, "orcid": "0000-0002-5880-8649" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Two-Dimensional Halide Perovskites: Tuning Electronic Activities of Defects", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: March 5, 2016. Revised: April 13, 2016. Publication Date (Web): April 21, 2016. \n\nY.L. thanks discussions with Professor Wan-Jian Yin and acknowledges the support from Resnick Prize Postdoctoral Fellowship at Caltech. H.X. and W.A.G. were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. DOE under Award No. DE-SC0004993. This research was also supported by NSF (CBET-1512759, program manager: Robert McCabe), DOE (DE FOA 0001276, program manager: James Davenport). This work used computational resources of National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. DOE under Contract DE-AC02-05CH11231, and the Extreme Science and Engineering Discovery Environment (XSEDE), which is supported by NSF Grant ACI-1053575. \n\nThe authors declare no competing financial interest.\n\nPublished - acs_2Enanolett_2E6b00964.pdf
Submitted - 1605.02422.pdf
Supplemental Material - nl6b00964_si_001.pdf
", "abstract": "Two-dimensional (2D) halide perovskites are emerging as promising candidates for nanoelectronics and optoelectronics. To realize their full potential, it is important to understand the role of those defects that can strongly impact material properties. In contrast to other popular 2D semiconductors (e.g., transition metal dichalcogenides MX_2) for which defects typically induce harmful traps, we show that the electronic activities of defects in 2D perovskites are significantly tunable. For example, even with a fixed lattice orientation one can change the synthesis conditions to convert a line defect (edge or grain boundary) from electron acceptor to inactive site without deep gap states. We show that this difference originates from the enhanced ionic bonding in these perovskites compared with MX_2. The donors tend to have high formation energies and the harmful defects are difficult to form at a low halide chemical potential. Thus, we unveil unique properties of defects in 2D perovskites and suggest practical routes to improve them.", "date": "2016-05-11", "date_type": "published", "publication": "Nano Letters", "volume": "16", "number": "5", "publisher": "American Chemical Society", "pagerange": "3335-3340", "id_number": "CaltechAUTHORS:20160428-094924238", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160428-094924238", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CBET-151275" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FOA-0001276" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF", "grant_number": "ACI-1053575" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.6b00964", "primary_object": { "basename": "1605.02422.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/1605.02422.pdf" }, "related_objects": [ { "basename": "acs_2Enanolett_2E6b00964.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/acs_2Enanolett_2E6b00964.pdf" }, { "basename": "nl6b00964_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xt843-srs47/files/nl6b00964_si_001.pdf" } ], "pub_year": "2016", "author_list": "Liu, Yuanyue; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/31ctk-1hg50", "eprint_id": 65099, "eprint_status": "archive", "datestamp": "2023-08-20 11:35:05", "lastmod": "2023-10-17 23:11:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Principles and implementations of electrolysis systems for water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 18 Jan 2016, Accepted 05 Feb 2016; First published online 12 Feb 2016. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nPublished - c6mh00016a.pdf
", "abstract": "Efforts to develop renewable sources of carbon-neutral fuels have brought a renewed focus to research and development of sunlight-driven water-splitting systems. Electrolysis of water to produce H_2 and O_2 gases is the foundation of such systems, is conceptually and practically simple, and has been practiced both in the laboratory and industrially for many decades. In this Focus article, we present the fundamentals of water splitting and describe practices which distinguish commercial water-electrolysis systems from simple laboratory-scale demonstrations.", "date": "2016-05-01", "date_type": "published", "publication": "Materials Horizons", "volume": "2016", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "169-173", "id_number": "CaltechAUTHORS:20160307-084720706", "issn": "2051-6347", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160307-084720706", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c6mh00016a", "primary_object": { "basename": "c6mh00016a.pdf", "url": "https://authors.library.caltech.edu/records/31ctk-1hg50/files/c6mh00016a.pdf" }, "pub_year": "2016", "author_list": "Xiang, Chengxiang; Papadantonakis, Kimberly M.; et el." }, { "id": "https://authors.library.caltech.edu/records/8031b-2ae18", "eprint_id": 67957, "eprint_status": "archive", "datestamp": "2023-08-20 11:29:02", "lastmod": "2023-10-19 22:08:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hattrick-Simpers-J-R", "name": { "family": "Hattrick-Simpers", "given": "Jason R." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Kusne-A-G", "name": { "family": "Kusne", "given": "A. Gilad" } } ] }, "title": "Perspective: Composition\u2013structure\u2013property mapping in high-throughput experiments: Turning data into knowledge", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Author(s). \u00a9 2016 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). \n\nReceived 15 February 2016; accepted 9 May 2016; published online 26 May 2016.\n\nJ.H.S gratefully acknowledges support from Advanced Research Projects Agency-Energy (ARPA-E), U.S. Department of Energy, under Award No. DE-AR0000492 and the SouthCarolina SmartState\u2122 Center for Strategic Approaches to the Generation of Electricity (SAGE). J.M.G. acknowledges support from the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy Award No. DE-SC0004993, and the Computational Sustainability Network, supported through National Science Foundation Expeditions in Computing Grant No. 1521687. The authors thank Carla Gomes and Ronan LeBras for insightful discussions.\n\nPublished - 1.4950995.pdf
", "abstract": "With their ability to rapidly elucidate composition-structure-property relationships, high-throughput experimental studies have revolutionized how materials are discovered, optimized, and commercialized. It is now possible to synthesize and characterize high-throughput libraries that systematically address thousands of individual cuts of fabrication parameter space. An unresolved issue remains transforming structural characterization data into phase mappings. This difficulty is related to the complex information present in diffraction and spectroscopic data and its variation with composition and processing. We review the field of automated phase diagram attribution and discuss the impact that emerging computational approaches will have in the generation of phase diagrams and beyond.", "date": "2016-05", "date_type": "published", "publication": "APL Materials", "volume": "4", "number": "5", "publisher": "American Institute of Physics", "pagerange": "Art. No. 053211", "id_number": "CaltechAUTHORS:20160616-071550684", "issn": "2166-532X", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160616-071550684", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "ARPA-E" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AR0000492" }, { "agency": "South Carolina Smart-State Center for Strategic Approaches to the Generation of Electricity (SAGE)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CCF-1521687" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4950995", "primary_object": { "basename": "1.4950995.pdf", "url": "https://authors.library.caltech.edu/records/8031b-2ae18/files/1.4950995.pdf" }, "pub_year": "2016", "author_list": "Hattrick-Simpers, Jason R.; Gregoire, John M.; et el." }, { "id": "https://authors.library.caltech.edu/records/f44wr-anc57", "eprint_id": 65617, "eprint_status": "archive", "datestamp": "2023-08-20 11:16:48", "lastmod": "2023-10-18 16:11:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Becerra-Stasiewicz-N", "name": { "family": "Becerra-Stasiewicz", "given": "Natalie" } }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Stability and self-passivation of copper vanadate photoanodes under chemical, electrochemical, and photoelectrochemical operation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 the Owner Societies. \n\nReceived 21 Jan 2016, Accepted 14 Mar 2016, First published online 14 Mar 2016. \n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Computational work was supported by the Materials Project (DOE Grant # EDCBEE) through the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-05CH11231. Use of the Stanford Synchrotron Radiation Lightsource is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Contract No. DE-AC02-76SF00515. The authors appreciate assistance from A. Mehta and D. van Campen (synchrotron XRD measurements), C. Xiang (Fig. 2 graphics), and S. Mitrovic (XPS measurements).\n\nPublished - C6CP00473C.pdf
Supplemental Material - c6cp00473c1_si.pdf
Supplemental Material - c6cp00473c2.xlsx
", "abstract": "Deployment of solar fuels technology requires photoanodes with\nlong term stability, which can be accomplished using light absorbers\nthat self-passivate under operational conditions. Several copper\nvanadates have been recently reported as promising photoanode\nmaterials, and their stability and self-passivation is demonstrated\nthrough a combination of Pourbaix calculations and combinatorial\nexperimentation.", "date": "2016-04-14", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "18", "number": "14", "publisher": "Royal Society of Chemistry", "pagerange": "9349-9352", "id_number": "CaltechAUTHORS:20160323-102320816", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160323-102320816", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "EDCBEE" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C6CP00473C", "primary_object": { "basename": "C6CP00473C.pdf", "url": "https://authors.library.caltech.edu/records/f44wr-anc57/files/C6CP00473C.pdf" }, "related_objects": [ { "basename": "c6cp00473c1_si.pdf", "url": "https://authors.library.caltech.edu/records/f44wr-anc57/files/c6cp00473c1_si.pdf" }, { "basename": "c6cp00473c2.xlsx", "url": "https://authors.library.caltech.edu/records/f44wr-anc57/files/c6cp00473c2.xlsx" } ], "pub_year": "2016", "author_list": "Zhou, Lan; Yan, Qimin; et el." }, { "id": "https://authors.library.caltech.edu/records/6jwpq-vsv45", "eprint_id": 64154, "eprint_status": "archive", "datestamp": "2023-08-20 11:14:30", "lastmod": "2023-10-17 19:33:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "570 mV photovoltage, stabilized n-Si/CoO_x heterojunction photoanodes fabricated using atomic layer deposition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 The Royal Society of Chemistry. \n\nReceived 4th December 2015, Accepted 8th January 2016. First published online 08 Jan 2016. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Atomic-force microscopy and UV-Vis spectroscopy were performed at the Molecular Materials Resource Center (MMRC) of the Beckman Institute at the California Institute of Technology. This work was additionally supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225.\n\nPublished - c5ee03655k.pdf
Supplemental Material - c5ee03655k1.pdf
", "abstract": "Heterojunction photoanodes, consisting of n-type crystalline Si(100) substrates coated with a thin \u223c50 nm film of cobalt oxide fabricated using atomic-layer deposition (ALD), exhibited photocurrent-onset potentials of \u2212205 \u00b1 20 mV relative to the formal potential for the oxygen-evolution reaction (OER), ideal regenerative solar-to-O_2(g) conversion efficiencies of 1.42 \u00b1 0.20%, and operated continuously for over 100 days (\u223c2500 h) in 1.0 M KOH(aq) under simulated solar illumination. The ALD CoO_x thin film: (i) formed a heterojunction with the n-Si(100) that provided a photovoltage of 575 mV under 1 Sun of simulated solar illumination; (ii) stabilized Si photoanodes that are otherwise unstable when operated in aqueous alkaline electrolytes; and, (iii) catalyzed the oxidation of water, thereby reducing the kinetic overpotential required for the reaction and increasing the overall efficiency relative to electrodes that do not have an inherently electrocatalytic coating. The process provides a simple, effective method for enabling the use of planar n-Si(100) substrates as efficient and durable photoanodes in fully integrated, photovoltaic-biased solar fuels generators.", "date": "2016-04-08", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "892-897", "id_number": "CaltechAUTHORS:20160202-092151363", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160202-092151363", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C5EE03655K", "primary_object": { "basename": "c5ee03655k.pdf", "url": "https://authors.library.caltech.edu/records/6jwpq-vsv45/files/c5ee03655k.pdf" }, "related_objects": [ { "basename": "c5ee03655k1.pdf", "url": "https://authors.library.caltech.edu/records/6jwpq-vsv45/files/c5ee03655k1.pdf" } ], "pub_year": "2016", "author_list": "Zhou, Xinghao; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/1mh21-7qp04", "eprint_id": 65626, "eprint_status": "archive", "datestamp": "2023-08-20 10:56:27", "lastmod": "2023-10-18 16:11:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Tolstova-Yulia", "name": { "family": "Tolstova", "given": "Yulia" } }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Shing-Amanda-M", "name": { "family": "Shing", "given": "Amanda M." } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Heteroepitaxial growth of Pt and Au thin films on MgO single crystals by bias-assisted sputtering", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ \n\nReceived: 04 January 2016; Accepted: 02 March 2016; Published online: 17 March 2016. \n\n\nThe authors gratefully acknowledge support from the Dow Chemical Company under the earth-abundant semiconductor project, and by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. This material is based upon work supported in part by the National Science Foundation (NSF) and the Department of Energy (DOE) under NSF CA No. EEC-1041895. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect those of NSF or DOE. \n\nAuthor Contributions: Y.T. designed and performed experiments and data analysis, and drafted the manuscript. S.T.O. and H.A.A. contributed to the writing. S.T.O. assisted with XRD data collection and interpretation of the data. A.M.S. contributed to discussion and interpretation of the data as well as assisted with experimental setup. H.A.A. supervised the project. All authors reviewed the manuscript. \n\nThe authors declare no competing financial interests.\n\nPublished - srep23232.pdf
", "abstract": "The crystallographic orientation of a metal affects its surface energy and structure, and has profound implications for surface chemical reactions and interface engineering, which are important in areas ranging from optoelectronic device fabrication to catalysis. However, it can be very difficult and expensive to manufacture, orient, and cut single crystal metals along different crystallographic orientations, especially in the case of precious metals. One approach is to grow thin metal films epitaxially on dielectric substrates. In this work, we report on growth of Pt and Au films on MgO single crystal substrates of (100) and (110) surface orientation for use as epitaxial templates for thin film photovoltaic devices. We develop bias-assisted sputtering for deposition of oriented Pt and Au films with sub-nanometer roughness. We show that biasing the substrate decreases the substrate temperature necessary to achieve epitaxial orientation, with temperature reduction from 600 to 350\u2009\u00b0C for Au, and from 750 to 550\u2009\u00b0C for Pt, without use of transition metal seed layers. In addition, this temperature can be further reduced by reducing the growth rate. Biased deposition with varying substrate bias power and working pressure also enables control of the film morphology and surface roughness.", "date": "2016-03-17", "date_type": "published", "publication": "Scientific Reports", "volume": "6", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 23232", "id_number": "CaltechAUTHORS:20160323-130316195", "issn": "2045-2322", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160323-130316195", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Dow Chemical Company" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "EEC-1041895" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/srep23232", "pmcid": "PMC4794713", "primary_object": { "basename": "srep23232.pdf", "url": "https://authors.library.caltech.edu/records/1mh21-7qp04/files/srep23232.pdf" }, "pub_year": "2016", "author_list": "Tolstova, Yulia; Omelchenko, Stefan T.; et el." }, { "id": "https://authors.library.caltech.edu/records/awscz-j6622", "eprint_id": 65505, "eprint_status": "archive", "datestamp": "2023-08-20 10:55:40", "lastmod": "2023-10-18 16:05:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Azhagurajan-Mukkannan", "name": { "family": "Azhagurajan", "given": "Mukkannan" } }, { "id": "Kajita-Tetsuya", "name": { "family": "Kajita", "given": "Tetsuya" } }, { "id": "Ito-Takashi", "name": { "family": "Itoh", "given": "Takashi" } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Itaya-Kingo", "name": { "family": "Itaya", "given": "Kingo" } } ] }, "title": "In Situ Visualization of Lithium Ion Intercalation into MoS_2 Single Crystals using Differential Optical Microscopy with Atomic Layer Resolution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. ACS Editors' Choice. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: November 12, 2015; Published: February 16, 2016. \n\nThe authors acknowledge Prof. G. Sazaki (Hokkaido University), Mr. Y. Saito (Olympus), and Mr. S. Kobayashi (Olympus) for developing and improving the LCM\u2212DIM system. The authors are grateful to Prof. M. Soriaga and Dr. J. Baricuatro (Joint Center for Artificial Photosynthesis, California Institute of Technology, Pasadena, United States) for their helpful suggestions and discussion of the paper. This work was supported by the Ministry of Education, Culture, Sports, Science and Technology of Japan under Grant 20245038 and in part by the New Energy and Industrial Technology Development Organization (NEDO).\n\nPublished - jacs_2E5b11849.pdf
Supplemental Material - ja5b11849_si_001.pdf
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Supplemental Material - ja5b11849_si_006.avi
", "abstract": "Atomic-level visualization of the intercalation of layered materials, such as metal chalcogenides, is of paramount importance in the development of high-performance batteries. In situ images of the dynamic intercalation of Li ions into MoS_2 single-crystal electrodes were acquired for the first time, under potential control, with the use of a technique combining laser confocal microscopy with differential interference microscopy. Intercalation proceeded via a distinct phase separation of lithiated and delithiated regions. The process started at the atomic steps of the first layer beneath the selvedge and progressed in a layer-by-layer fashion. The intercalated regions consisted of Li-ion channels into which the newly inserted Li ions were pushed atom-by-atom. Interlayer diffusion of Li ions was not observed. Deintercalation was also clearly imaged and was found to transpire in a layer-by-layer mode. The intercalation and deintercalation processes were chemically reversible and can be repeated many times within a few atomic layers. Extensive intercalation of Li ions disrupted the atomically flat surface of MoS_2 because of the formation of small lithiated domains that peeled off from the surface of the crystal. The current\u2013potential curves of the intercalation and deintercalation processes were independent of the scan rate, thereby suggesting that the rate-determining step was not governed by Butler\u2013Volmer kinetics.", "date": "2016-03-16", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "10", "publisher": "American Chemical Society", "pagerange": "3355-3361", "id_number": "CaltechAUTHORS:20160321-081806933", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160321-081806933", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Ministry of Education, Culture, Sports, Science and Technology (MEXT)", "grant_number": "20245038" }, { "agency": "New Energy and Industrial Technology Development Organization (NEDO)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.5b11849", "primary_object": { "basename": "ja5b11849_si_004.avi", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_004.avi" }, "related_objects": [ { "basename": "ja5b11849_si_005.avi", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_005.avi" }, { "basename": "ja5b11849_si_006.avi", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_006.avi" }, { "basename": "jacs_2E5b11849.pdf", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/jacs_2E5b11849.pdf" }, { "basename": "ja5b11849_si_001.pdf", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_001.pdf" }, { "basename": "ja5b11849_si_002.avi", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_002.avi" }, { "basename": "ja5b11849_si_003.avi", "url": "https://authors.library.caltech.edu/records/awscz-j6622/files/ja5b11849_si_003.avi" } ], "pub_year": "2016", "author_list": "Azhagurajan, Mukkannan; Kajita, Tetsuya; et el." }, { "id": "https://authors.library.caltech.edu/records/g7vcr-qbe37", "eprint_id": 61970, "eprint_status": "archive", "datestamp": "2023-08-22 17:35:26", "lastmod": "2023-10-25 16:06:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Shaner-Matthew-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Crumlin-Ethan-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Protection of inorganic semiconductors for sustained, efficient photoelectrochemical water oxidation", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Artificial photosynthesis; Photoelectrochemistry; Corrosion; Catalysis", "note": "\u00a9 2015 Elsevier B.V. \n\nReceived 3 July 2015; Received in revised form 18 August 2015; Accepted 20 August 2015; Available online 25 October 2015. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as well as by the Moore Foundation. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract no. DE-AC02-05CH11231. The authors thank Van Seebass for assistance in the preparation of this manuscript.", "abstract": "Small-band-gap (E_g < 2 eV) semiconductors must be stabilized for use in integrated devices that convert solar energy into the bonding energy of a reduced fuel, specifically H_2(g) or a reduced-carbon species such as CH_3OH or CH_4. To sustainably and scalably complete the fuel cycle, electrons must be liberated through the oxidation of water to O_2(g). Strongly acidic or strongly alkaline electrolytes are needed to enable efficient and intrinsically safe operation of a full solar-driven water-splitting system. However, under water-oxidation conditions, the small-band-gap semiconductors required for efficient cell operation are unstable, either dissolving or forming insulating surface oxides. We describe herein recent progress in the protection of semiconductor photoanodes under such operational conditions. We specifically describe the properties of two protective overlayers, TiO_2/Ni and NiO_x, both of which have demonstrated the ability to protect otherwise unstable semiconductors for >100 h of continuous solar-driven water oxidation when in contact with a highly alkaline aqueous electrolyte (1.0 M KOH(aq)). The stabilization of various semiconductor photoanodes is reviewed in the context of the electronic characteristics and a mechanistic analysis of the TiO_2 films, along with a discussion of the optical, catalytic, and electronic nature of NiO_x films for stabilization of semiconductor photoanodes for water oxidation.", "date": "2016-03-15", "date_type": "published", "publication": "Catalysis Today", "volume": "262", "publisher": "Elsevier", "pagerange": "11-23", "id_number": "CaltechAUTHORS:20151106-151700406", "issn": "0920-5861", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151106-151700406", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.cattod.2015.08.017", "pub_year": "2016", "author_list": "Lichterman, Michael F.; Sun, Ke; et el." }, { "id": "https://authors.library.caltech.edu/records/qbdyf-cc997", "eprint_id": 65830, "eprint_status": "archive", "datestamp": "2023-08-20 10:50:55", "lastmod": "2023-10-18 16:50:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Meng-Xiangying", "name": { "family": "Meng", "given": "Xiangying" } }, { "id": "Wang-Lu", "name": { "family": "Wang", "given": "Lu" }, "orcid": "0000-0001-5263-3123" }, { "id": "Liu-Dongyan", "name": { "family": "Liu", "given": "Dongyan" } }, { "id": "Wen-Xiaohong", "name": { "family": "Wen", "given": "Xiaohong" } }, { "id": "Zhu-Qiang", "name": { "family": "Zhu", "given": "Qiang" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "An-Qi", "name": { "family": "An", "given": "Qi" }, "orcid": "0000-0003-4838-6232" } ] }, "title": "Discovery of Fe_2 =P-Type Ti(Zr/Hf)_2O_6 Photocatalysts toward Water Splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: November 3, 2015. Revised: January 27, 2016. Publication Date (Web): February 11, 2016. \n\nThis work was financially supported by the Fundamental Research Funds for the Central Universities (N150502002) and National High Technology Research and Development Program of China (Grant No. 2013AA031601). All calculations are performed on the stampede clusters at China Northeastern Super-Computing Center. Q.A. and W.A.G were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nAuthor Contributions: X.M., L.W., and D.L. performed USPEX structure-searching; X.M., L.W., and X.W. calculated properties of the compounds. All authors contributed to data analysis. X.M. and Q.Z. wrote the manuscript with input from all authors. X.M. directed the project. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cm5b04256_si_001.cif
Supplemental Material - cm5b04256_si_002.cif
Supplemental Material - cm5b04256_si_003.pdf
", "abstract": "We report the discovery of Fe_2P-type TiO_2-based photocatalysts, TiZr_2O_6 and TiHf_2O_6, through first-principle calculations. Appearing as the solid solutions of TiO_2 and Zr(Hf)O_2 at 150 GPa, Ti (Zr/Hf)_2O_6 unit cells are constructed by replacing two Ti atoms with Zr or Hf atoms in the pure Fe_2P-type TiO_2 lattice. The two compounds are mechanically and dynamically stable at ambient conditions. The electronic structure calculations predict direct bandgaps of 2.29 and 2.65 eV for TiZr_2O_6 and TiHf_2O_6, respectively. Significant evidence in the electronic properties prove both TiZr_2O_6 and TiHf_2O_6 to be attractive photocatalysts in the visible light region, but TiZr_2O_6 is more promising in the application of hydrogen generation by water splitting. Thus, instead of element doping, we narrow the bandgap of TiO_2 by developing intrinsic stable semiconductors from scratch. The rational design in this work of predicting high-pressure phases and stabilizing them open a way for prompting photoelectrochemical activities of photocatalysts.", "date": "2016-03-08", "date_type": "published", "publication": "Chemistry of Materials", "volume": "28", "number": "5", "publisher": "American Chemical Society", "pagerange": "1335-1342", "id_number": "CaltechAUTHORS:20160401-073356309", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160401-073356309", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Fundamental Research Funds for the Central Universities", "grant_number": "N150502002" }, { "agency": "National High Technology Research and Development Program of China", "grant_number": "2013AA031601" }, { "agency": "Joint Center for Artificial Photosynthesis" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.chemmater.5b04256", "primary_object": { "basename": "cm5b04256_si_003.pdf", "url": "https://authors.library.caltech.edu/records/qbdyf-cc997/files/cm5b04256_si_003.pdf" }, "related_objects": [ { "basename": "cm5b04256_si_001.cif", "url": "https://authors.library.caltech.edu/records/qbdyf-cc997/files/cm5b04256_si_001.cif" }, { "basename": "cm5b04256_si_002.cif", "url": "https://authors.library.caltech.edu/records/qbdyf-cc997/files/cm5b04256_si_002.cif" } ], "pub_year": "2016", "author_list": "Meng, Xiangying; Wang, Lu; et el." }, { "id": "https://authors.library.caltech.edu/records/cm9jr-17a34", "eprint_id": 65510, "eprint_status": "archive", "datestamp": "2023-08-20 10:49:23", "lastmod": "2023-10-18 16:05:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Crowley-J-M", "name": { "family": "Crowley", "given": "Jason M." } }, { "id": "Tahir-Kheli-J", "name": { "family": "Tahir-Kheli", "given": "Jamil" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Resolution of the Band Gap Prediction Problem for Materials Design", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: December 24, 2015. Accepted: March 4, 2016. \n\nWe thank NSF (DMREF-1436985) and JCAP (Joint Center of\nArtificial Photosynthesis, DOE DE-SC0004993) for partial\nsupport. We thank Giulia Galli, Yuan Ping, and Peter A. Schultz for useful comments. We also thank Hai Xiao, Richard P. Muller, and Carver A. Mead for fruitful discussions.\n\nPublished - acs_2Ejpclett_2E5b02870.pdf
Supplemental Material - jz5b02870_si_001.pdf
", "abstract": "An important property with any new material is the band gap. Standard density functional theory methods grossly underestimate band gaps. This is known as the band gap problem. Here, we show that the hybrid B3PW91 density functional returns band gaps with a mean absolute deviation (MAD) from experiment of 0.22 eV over 64 insulators with gaps spanning a factor of 500 from 0.014 to 7 eV. The MAD is 0.28 eV over 70 compounds with gaps up to 14.2 eV, with a mean error of \u22120.03 eV. To benchmark the quality of the hybrid method, we compared the hybrid method to the rigorous GW many-body perturbation theory method. Surprisingly, the MAD for B3PW91 is about 1.5 times smaller than the MAD for GW. Furthermore, B3PW91 is 3\u20134 orders of magnitude faster computationally. Hence, B3PW91 is a practical tool for predicting band gaps of materials before they are synthesized and represents a solution to the band gap prediction problem.", "date": "2016-03-04", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "2016", "number": "7", "publisher": "American Chemical Society", "pagerange": "1198-1203", "id_number": "CaltechAUTHORS:20160321-091914241", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160321-091914241", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMREF-1436985" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.5b02870", "primary_object": { "basename": "acs_2Ejpclett_2E5b02870.pdf", "url": "https://authors.library.caltech.edu/records/cm9jr-17a34/files/acs_2Ejpclett_2E5b02870.pdf" }, "related_objects": [ { "basename": "jz5b02870_si_001.pdf", "url": "https://authors.library.caltech.edu/records/cm9jr-17a34/files/jz5b02870_si_001.pdf" } ], "pub_year": "2016", "author_list": "Crowley, Jason M.; Tahir-Kheli, Jamil; et el." }, { "id": "https://authors.library.caltech.edu/records/4jd58-64z38", "eprint_id": 64740, "eprint_status": "archive", "datestamp": "2023-08-22 17:33:26", "lastmod": "2023-10-17 21:50:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Torelli-D-A", "name": { "family": "Torelli", "given": "Daniel A." }, "orcid": "0000-0002-6222-817X" }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Crompton-J-C", "name": { "family": "Crompton", "given": "J. Chance" } }, { "id": "Javier-A", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Thompson-J-R", "name": { "family": "Thompson", "given": "Joanthan R." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Nickel\u2212Gallium-Catalyzed Electrochemical Reduction of CO_2 to Highly Reduced Products at Low Overpotentials", "ispublished": "pub", "full_text_status": "public", "keywords": "CO_2 reduction; electrocatalysis; nickel gallium; NiGa; ethane; methane; low overpotential; C_2 production", "note": "\u00a9 2016 American Chemical Society. \n\nReceived: December 17, 2015. Publication Date (Web): February 17, 2016. \n\nThe authors would like to thank Prof. Matthew McDowell for his help with TEM and insightful discussions, Dr. Ivonne Ferrer for her help with GC setup and calibration, and Dr. Kimberly Papadantonakis for help with editing. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. D.A.T. recognizes a Graduate Research Fellowship from the National Science Foundation for support. S.A.F. acknowledges the Resnick Sustainability Institute at Caltech for a Postdoctoral Fellowship. J.C.C. acknowledges support from the Department of Defense through the National Defense Science & Engineering Graduate Fellowship Program. N.S.L. acknowledges support through the Multidisciplinary University Research Initiative (MURI) under AFOSR Award No. FA9550-10-1-0572. \n\nThese authors contributed equally (D.A.T. and S.A.F.). \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - cs5b02888_si_001.pdf
", "abstract": "We report the electrocatalytic reduction of CO_2 to the highly reduced C_2 products, ethylene and ethane, as well as to the fully reduced C_1 product, methane, on three different phases of nickel\u2013gallium (NiGa, Ni_3Ga, and Ni_5Ga_3) films prepared by drop-casting. In aqueous bicarbonate electrolytes at neutral pH, the onset potential for methane, ethylene, and ethane production on all three phases was found to be \u22120.48 V versus the reversible hydrogen electrode (RHE), among the lowest onset potentials reported to date for the production of C_2 products from CO_2. Similar product distributions and onset potentials were observed for all three nickel\u2013gallium stoichiometries tested. The onset potential for the reduction of CO_2 to C_2 products at low current densities catalyzed by nickel\u2013gallium was >250 mV more positive than that of polycrystalline copper, and approximately equal to that of single crystals of copper, which have some of the lowest overpotentials to date for the reduction of CO_2 to C_2 products and methane. The nickel\u2013gallium films also reduced CO to ethylene, ethane, and methane, consistent with a CO_2 reduction mechanism that first involves the reduction of CO2 to CO. Isotopic labeling experiments with ^(13)CO_2 confirmed that the detected products were produced exclusively by the reduction of CO_2.", "date": "2016-03-04", "date_type": "published", "publication": "ACS Catalysis", "volume": "6", "number": "3", "publisher": "American Chemical Society", "pagerange": "2100-2104", "id_number": "CaltechAUTHORS:20160224-132719916", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160224-132719916", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "National Defense Science and Engineering Graduate (NDSEG) Fellowship" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-10-1-0572" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acscatal.5b02888", "primary_object": { "basename": "cs5b02888_si_001.pdf", "url": "https://authors.library.caltech.edu/records/4jd58-64z38/files/cs5b02888_si_001.pdf" }, "pub_year": "2016", "author_list": "Torelli, Daniel A.; Francis, Sonja A.; et el." }, { "id": "https://authors.library.caltech.edu/records/p7g8k-k3362", "eprint_id": 62931, "eprint_status": "archive", "datestamp": "2023-08-20 10:28:24", "lastmod": "2023-10-25 22:00:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Ferrer-I-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "Benchmarking nanoparticulate metal oxide electrocatalysts for the alkaline water oxidation reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. \n\nReceived 22nd September 2015; Accepted 25th November 2015; First published online 27 Nov 2015. \n\nThis article is part of themed collection: Water splitting and photocatalysis. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We would like to acknowledge much assistance in BET measurements by Kurt M. Van Allsburg.\n\nPublished - c5ta07586f.pdf
Supplemental Material - c5ta07586f1_si.pdf
", "abstract": "Nanoparticulate metal-oxide catalysts are among the most prevalent systems for alkaline water oxidation. However, comparisons of the electrochemical performance of these materials have been challenging due to the different methods of attachment, catalyst loadings, and electrochemical test conditions reported in the literature. Herein, we have leveraged a conventional drop-casting method that allows for the successful adhesion of a wide range of nanoparticulate catalysts to glassy-carbon electrode surfaces. We have applied this adhesion method to prepare catalyst films from 16 crystalline metal-oxide nanoparticles with a constant loading of 0.8 mg cm^(\u22122), and evaluated the resulting nanoparticulate films for the oxygen evolution reaction under conditions relevant to an integrated solar fuels device. In general, the activities of the adhered nanoparticulate films are similar to those of thin-film catalysts prepared by electrodeposition or sputtering, achieving 10 mA cm^(\u22122) current densities per geometric area at overpotentials of \u223c0.35\u20130.5 V.", "date": "2016-02-28", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "4", "number": "8", "publisher": "Royal Society of Chemistry", "pagerange": "3068-3076", "id_number": "CaltechAUTHORS:20151215-102451419", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151215-102451419", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ta07586f", "primary_object": { "basename": "c5ta07586f.pdf", "url": "https://authors.library.caltech.edu/records/p7g8k-k3362/files/c5ta07586f.pdf" }, "related_objects": [ { "basename": "c5ta07586f1_si.pdf", "url": "https://authors.library.caltech.edu/records/p7g8k-k3362/files/c5ta07586f1_si.pdf" } ], "pub_year": "2016", "author_list": "Jung, Suho; McCrory, Charles C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/1b7d4-0q641", "eprint_id": 64156, "eprint_status": "archive", "datestamp": "2023-08-20 10:24:37", "lastmod": "2023-10-17 19:33:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Richter-Matthias-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Beardslee-Joseph-A", "name": { "family": "Beardslee", "given": "Joseph" } }, { "id": "Mayer-Thomas", "name": { "family": "Mayer", "given": "Thomas" } }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Electrical, Photoelectrochemical, and Photoelectron Spectroscopic Investigation of the Interfacial Transport and Energetics of Amorphous TiO\u2082/Si Heterojunctions", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: September 18, 2015. Revised: December 7, 2015. Publication Date (Web): December 15, 2015. \n\nThis work was supported through the Office of Science of the\nU.S. Department of Energy under Award DE-SC0004993 to\nthe Joint Center for Artificial Photosynthesis, a DOE Energy\nInnovation Hub. The authors thank Dr. Gang Liu and Prof.\nChongwu Zhou at the University of Southern California for\ntheir support of variable-temperature solid-state transport\nmeasurements. The authors also acknowledge Dr. Slobodan\nMitrovic and Natalie Becerra for assistance in the collection of XPS data, as well as Dr. Kimberley Papadantonakis for assistance with editing this manuscript. \n\nS.H. and M.H.R. contributed equally to this work. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b09121_si_001.pdf
", "abstract": "Solid-state electrical, photoelectrochemical, and photoelectron spectroscopic techniques have been used to characterize the behavior and electronic structure of interfaces between n-Si, n\u207a-Si, or p\u207a-Si surfaces and amorphous coatings of TiO\u2082 formed using atomic-layer deposition. Photoelectrochemical measurements of n-Si/TiO\u2082/Ni interfaces in contact with a series of one-electron, electrochemically reversible redox systems indicated that the n-Si/TiO\u2082/Ni structure acted as a buried junction whose photovoltage was independent of the formal potential of the contacting electrolyte. Solid-state current\u2013voltage analysis indicated that the built-in voltage of the n-Si/TiO\u2082 heterojunction was \u223c0.7 V, with an effective Richardson constant \u223c1/100th of the value of typical Si/metal Schottky barriers. X-ray photoelectron spectroscopic data allowed formulation of energy band-diagrams for the n-Si/TiO\u2082, n\u207a-Si/TiO\u2082, and p\u207a-Si/TiO\u2082 interfaces. The XPS data were consistent with the rectifying behavior observed for amorphous TiO\u2082 interfaces with n-Si and n\u207a-Si surfaces and with an ohmic contact at the interface between amorphous TiO\u2082 and p\u207a-Si.", "date": "2016-02-18", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "120", "number": "6", "publisher": "American Chemical Society", "pagerange": "3117-3129", "id_number": "CaltechAUTHORS:20160202-092151875", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160202-092151875", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.5b09121", "primary_object": { "basename": "jp5b09121_si_001.pdf", "url": "https://authors.library.caltech.edu/records/1b7d4-0q641/files/jp5b09121_si_001.pdf" }, "pub_year": "2016", "author_list": "Hu, Shu; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/2y54h-z8z44", "eprint_id": 63116, "eprint_status": "archive", "datestamp": "2023-08-20 10:04:32", "lastmod": "2023-10-25 23:33:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Guevarra-Dan", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Shinde-Aniketa-A", "name": { "family": "Shinde", "given": "A." }, "orcid": "0000-0003-2386-3848" }, { "id": "Suram-Santosh-K", "name": { "family": "Suram", "given": "S. K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Sharp-Ian-D", "name": { "family": "Sharp", "given": "I. D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Toma-Francesca-M", "name": { "family": "Toma", "given": "F. M." }, "orcid": "0000-0003-2332-0798" }, { "id": "Haber-Joel-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Development of solar fuels photoanodes through combinatorial integration of Ni\u2013La\u2013Co\u2013Ce oxide catalysts on BiVO\u2084", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. \n\nReceived 17th November 2015, Accepted 9th December 2015, First published online 09 Dec 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Citrine Informatics (www.citrine.io) for data hosting. The raw potentiostat and spectrometer data for the anodic sweep of the CV for each photoanode are available at links.citrination.com/ni-la-co-ce.\n\nPublished - c5ee03488d.pdf
Supplemental Material - c5ee03488d1_si.pdf
", "abstract": "The development of an efficient photoanode remains the primary materials challenge in the establishment of a scalable technology for solar water splitting. The typical photoanode architecture consists of a semiconductor light absorber coated with a metal oxide that serves a combination of functions, including corrosion protection, electrocatalysis, light trapping, hole transport, and elimination of deleterious recombination sites. To date, such coatings have been mostly limited to simple materials such as TiO\u2082 and Co-Pi, with extensive experimental and theoretical effort required to provide an understanding of the physics and chemistry of the semiconductor-coating interface. To provide a more efficient exploration of metal oxide coatings for a given light absorber, we introduce a high throughput methodology wherein a uniform BiVO\u2084 thin film is coated with 858 unique metal oxides covering a range of metal oxide loadings and the full Ni\u2013La\u2013Co\u2013Ce oxide quaternary composition space. Photoelectrochemical characterization of each photoanode reveals that approximately one third of the coatings lower the photoanode performance while select combinations of metal oxide composition and loading provide up to a 14-fold increase in the maximum photoelectrochemical power generation for oxygen evolution in pH 13 electrolyte. Particular Ce-rich coatings also exhibit an anti-reflection effect that further amplifies the performance, yielding a 20-fold enhancement in power conversion efficiency compared to bare BiVO\u2084. By use of in situ optical spectroscopy and comparisons between the metal oxide coatings and their extrinsic optical and electrocatalytic properties, we present a suite of data-driven discoveries, including composition regions which form optimal interfaces with BiVO\u2084 and photoanodes that are suitable for integration with a photocathode due to their excellent power conversion and solar transmission efficiencies. The high throughput experimentation and informatics provides a powerful platform for both identifying the pertinent interfaces for further study and discovering high performance photoanodes for incorporation into efficient water splitting devices.", "date": "2016-02", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "565-580", "id_number": "CaltechAUTHORS:20151221-160606238", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151221-160606238", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ee03488d", "primary_object": { "basename": "c5ee03488d1_si.pdf", "url": "https://authors.library.caltech.edu/records/2y54h-z8z44/files/c5ee03488d1_si.pdf" }, "related_objects": [ { "basename": "c5ee03488d.pdf", "url": "https://authors.library.caltech.edu/records/2y54h-z8z44/files/c5ee03488d.pdf" } ], "pub_year": "2016", "author_list": "Guevarra, D.; Shinde, A.; et el." }, { "id": "https://authors.library.caltech.edu/records/akpy1-bjn52", "eprint_id": 63881, "eprint_status": "archive", "datestamp": "2023-08-20 09:59:13", "lastmod": "2023-10-17 17:15:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Research opportunities to advance solar energy utilization", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2016 American Association for the Advancement of Science. \n\nWe acknowledge the NSF, CHE-1214152; the DOE Office of Science through the Joint Center for Artificial Photosynthesis, grant DE-SC0004993; and the DOE Office of Science, grant DE-FG02-03ER15483; and the Gordon and Betty Moore Foundation, grant 1225; for support that enabled the preparation of this Review, and M. Shaner for assistance in the preparation of this manuscript.", "abstract": "Major developments, as well as remaining challenges and the associated research opportunities, are evaluated for three technologically distinct approaches to solar energy utilization: solar electricity, solar thermal, and solar fuels technologies. Much progress has been made, but research opportunities are still present for all approaches. Both evolutionary and revolutionary technology development, involving foundational research, applied research, learning by doing, demonstration projects, and deployment at scale will be needed to continue this technology-innovation ecosystem. Most of the approaches still offer the potential to provide much higher efficiencies, much lower costs, improved scalability, and new functionality, relative to the embodiments of solar energy-conversion systems that have been developed to date.", "date": "2016-01-22", "date_type": "published", "publication": "Science", "volume": "351", "number": "6271", "publisher": "American Association for the Advancement of Science", "pagerange": "Art. No. aad1920", "id_number": "CaltechAUTHORS:20160122-095830294", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160122-095830294", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "1225" } ] }, "collection": "CaltechAUTHORS", "local_group": { "items": [ { "id": "JCAP", "value": "JCAP" } ] }, "doi": "10.1126/science.aad1920", "pub_year": "2016", "author_list": "Lewis, Nathan S." }, { "id": "https://authors.library.caltech.edu/records/k5jty-67y47", "eprint_id": 63536, "eprint_status": "archive", "datestamp": "2023-08-20 09:57:14", "lastmod": "2023-10-25 23:53:59", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" } ] }, "title": "Mechanistic Explanation of the pH Dependence and Onset Potentials for Hydrocarbon Products from Electrochemical Reduction of CO on Cu (111)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: October 30, 2015. Publication Date (Web): December 30, 2015. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. We are grateful to Dr. Robert J. Nielsen, Dr. Manny Soriaga, and Mr. Yufeng Huang for helpful discussions. The computations were carried out on computing resources Zwicky (Caltech) and NERSC. \n\nThe authors declare no competing financial interest.\n\nPublished - jacs_2E5b11390.pdf
Supplemental Material - ja5b11390_si_001.pdf
", "abstract": "Energy and environmental concerns demand development of more efficient and selective electrodes for electrochemical reduction of CO_2 to form fuels and chemicals. Since Cu is the only pure metal exhibiting reduction to form hydrocarbon chemicals, we focus here on the Cu (111) electrode. We present a methodology for density functional theory calculations to obtain accurate onset electrochemical potentials with explicit constant electrochemical potential and pH effects using implicit solvation. We predict the atomistic mechanisms underlying electrochemical reduction of CO, finding that (1) at acidic pH, the C_1 pathway proceeds through COH to CHOH to form CH_4 while C_2 (C_3) pathways are kinetically blocked; (2) at neutral pH, the C_1 and C_2 (C_3) pathways share the COH common intermediate, where the branch to C\u2013C coupling is realized by a novel CO\u2013COH pathway; and (3) at high pH, early C\u2013C coupling through adsorbed CO dimerization dominates, suppressing the C1 pathways by kinetics, thereby boosting selectivity for multi-carbon products.", "date": "2016-01-20", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "138", "number": "2", "publisher": "American Chemical Society", "pagerange": "483-486", "id_number": "CaltechAUTHORS:20160111-095847659", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160111-095847659", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1201", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.5b11390", "primary_object": { "basename": "ja5b11390_si_001.pdf", "url": "https://authors.library.caltech.edu/records/k5jty-67y47/files/ja5b11390_si_001.pdf" }, "related_objects": [ { "basename": "jacs_2E5b11390.pdf", "url": "https://authors.library.caltech.edu/records/k5jty-67y47/files/jacs_2E5b11390.pdf" } ], "pub_year": "2016", "author_list": "Xiao, Hai; Cheng, Tao; et el." }, { "id": "https://authors.library.caltech.edu/records/szdnf-xv968", "eprint_id": 61987, "eprint_status": "archive", "datestamp": "2023-08-20 09:49:42", "lastmod": "2023-10-25 16:07:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Velazquez-J-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Esposito-D-V", "name": { "family": "Esposito", "given": "Daniel V." }, "orcid": "0000-0002-0550-801X" }, { "id": "Pieterick-A-P", "name": { "family": "Pieterick", "given": "Adam" } }, { "id": "Pala-R-A", "name": { "family": "Pala", "given": "Ragip" } }, { "id": "Sun-Guofeng", "name": { "family": "Sun", "given": "Guofeng" } }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A scanning probe investigation of the role of surface motifs in the behavior of p-WSe_2 photocathodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Royal Society of Chemistry. \n\nReceived 17 Aug 2015, Accepted 08 Oct 2015. First published online 08 Oct 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. Additional support for this work was provided by BP. JMV acknowledges support through an NRC Ford Foundation Postdoctoral Fellowship and the U.S. Department of Energy under Award No. DE-SC0004993. JJ thanks the Camille and Henry Dreyfus Foundation for financial support through its postdoctoral fellowship program in environmental chemistry and the U.S. Department of Energy, Office of Basic Energy Sciences under Award No. DE-FG02-03ER15483. DVE acknowledges support from the NIST NRC Fellowship program. JMV, JJ, and DVE also acknowledge the NIST Center for Nanoscale Science and Technology for use of its facilities for some SPCM measurements. SA acknowledges support from a United States Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under the EERE Fuel Cell Technologies Program. Certain commercial equipment, instruments, and materials are identified in this paper to foster understanding. Such identification does not imply recommendation or endorsement by the National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are the best available for the purpose.\n\nPublished - A_scanning_probe_investigation_of_the_role_of_surface_motifs_in_the_behavior_of_p-WSe2_photocathodes.pdf
Supplemental Material - c5ee02530c1.pdf
", "abstract": "The spatial variation in the photoelectrochemical performance for the reduction of an aqueous one-electron redox couple, Ru(NH_3)_6^(3+/2+), and for the evolution of H_2(g) from 0.5 M H_2SO_4(aq) at the surface of bare or Pt-decorated p-type WSe_2 photocathodes has been investigated in situ using scanning photocurrent microscopy (SPCM). The measurements revealed significant differences in the charge-collection performance (quantified by the values of external quantum yields, \u03a6_(ext)) on various macroscopic terraces. Local spectral response measurements indicated a variation in the local electronic structure among the terraces, which was consistent with a non-uniform spatial distribution of sub-band-gap states within the crystals. The photoconversion efficiencies of Pt-decorated p-WSe_2 photocathodes were greater for the evolution of H_2(g) from 0.5 M H_2SO_4 than for the reduction of Ru(NH_3)_6^(3+/2+), and terraces that exhibited relatively low values of \u03a6_(ext) for the reduction of Ru(NH_3)_6^(3+/2+) could in some cases yield values of \u03a6_(ext) for the evolution of H_2(g) comparable to the values of \u03a6_(ext) yielded by the highest-performing terraces. Although the spatial resolution of the techniques used in this work frequently did not result in observation of the effect of edge sites on photocurrent efficiency, some edge effects were observed in the measurements; however the observed edge effects differed among edges, and did not appear to determine the performance of the electrodes.", "date": "2016-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "9", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "164-175", "id_number": "CaltechAUTHORS:20151109-102020642", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151109-102020642", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Ford Foundation" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "National Research Council" }, { "agency": "BP" }, { "agency": "EERE Fuel Cell Technologies Program" }, { "agency": "National Institute of Standards and Technology (NIST)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C5EE02530C", "primary_object": { "basename": "A_scanning_probe_investigation_of_the_role_of_surface_motifs_in_the_behavior_of_p-WSe2_photocathodes.pdf", "url": "https://authors.library.caltech.edu/records/szdnf-xv968/files/A_scanning_probe_investigation_of_the_role_of_surface_motifs_in_the_behavior_of_p-WSe2_photocathodes.pdf" }, "related_objects": [ { "basename": "c5ee02530c1.pdf", "url": "https://authors.library.caltech.edu/records/szdnf-xv968/files/c5ee02530c1.pdf" } ], "pub_year": "2016", "author_list": "Velazquez, Jesus M.; John, Jimmy; et el." }, { "id": "https://authors.library.caltech.edu/records/5xmdh-par02", "eprint_id": 63346, "eprint_status": "archive", "datestamp": "2023-08-20 09:41:27", "lastmod": "2023-10-25 23:44:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Brown-A-M", "name": { "family": "Brown", "given": "Ana M." } }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Nonradiative Plasmon Decay and Hot Carrier Dynamics: Effects of Phonons, Surfaces, and Geometry", "ispublished": "pub", "full_text_status": "restricted", "keywords": "surface plasmons, hot carriers, transport, resistivity, dielectric response, density functional theory", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: October 1, 2015; Accepted: December 10, 2015; Publication Date (Web): December 10, 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Calculations in this work used the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science o the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute. A.B. is supported by a National Science Foundation Graduate Research Fellowship, a Link Foundation Energy Fellowship, and the DOE Light\u2212Material Interactions in Energy Conversion Energy Frontier Research Center (DESC0001293). \n\nThe authors declare no competing financial interest.", "abstract": "The behavior of metals across a broad frequency range from microwave to ultraviolet frequencies is of interest in plasmonics, nanophotonics, and metamaterials. Depending on the frequency, losses of collective excitations in metals can be predominantly classical resistive effects or Landau damping. In this context, we present first-principles calculations that capture all of the significant microscopic mechanisms underlying surface plasmon decay and predict the initial excited carrier distributions so generated. Specifically, we include ab initio predictions of phonon-assisted optical excitations in metals, which are critical to bridging the frequency range between resistive losses at low frequencies and direct interband transitions at high frequencies. In the commonly used plasmonic materials, gold, silver, copper, and aluminum, we find that resistive losses compete with phonon-assisted carrier generation below the interband threshold, but hot carrier generation via direct transitions dominates above threshold. Finally, we predict energy-dependent lifetimes and mean free paths of hot carriers, accounting for electron\u2013electron and electron\u2013phonon scattering, to provide insight toward transport of plasmonically generated carriers at the nanoscale.", "date": "2016-01", "date_type": "published", "publication": "ACS Nano", "volume": "10", "number": "1", "publisher": "American Chemical Society", "pagerange": "957-966", "id_number": "CaltechAUTHORS:20160104-150344444", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-150344444", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Link Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001293" } ] }, "other_numbering_system": { "items": [ { "id": "1204", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acsnano.5b06199", "pub_year": "2016", "author_list": "Brown, Ana M.; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/k3tyh-n2h33", "eprint_id": 64889, "eprint_status": "archive", "datestamp": "2023-08-20 09:34:25", "lastmod": "2023-10-17 21:57:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Pien-Alex", "name": { "family": "Pien", "given": "Alex" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Si/TiO_2 Tandem-Junction Microwire Arrays for Unassisted Solar-Driven Water Splitting", "ispublished": "pub", "full_text_status": "public", "keywords": "Photoelectrochemistry Silicon Tandem Junction Water splitting", "note": "\u00a9 2016 The Electrochemical Society. \n\nManuscript submitted October 23, 2015; revised manuscript received December 17, 2015. Published January 15, 2016. \n\nThe authors acknowledge Stefan Omelchenko for assistance with the XRD measurements, John Lloyd for discussions about the cTLM measurements and Dr. Shawn Chatman for providing the Xe arc lamp spectral irradiance data. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993. M.R.S.\nacknowledges the Resnick Sustainability Institute for a graduate fellowship.\n\nPublished - J._Electrochem._Soc.-2016-Shaner-H261-4.pdf
Supplemental Material - README.txt
", "abstract": "Tandem-junction microwire array photoelectrodes have been fabricated by coating np^+-Si radial homojunction microwire arrays sequentially with fluorine-doped tin oxide (FTO) and titanium dioxide (TiO_2). These photoelectrodes effected unassisted water splitting under simulated 1 Sun conditions with an open-circuit potential (E_(oc)) of \u22121.5 V vs the formal potential for oxygen evolution, E^(0\u2032)(OH^\u2212/O_2), a current density at E = E^(0\u2032)(OH^\u2212/O_2) of 0.78 mA cm^(\u22122), a fill factor (\u2009ff\u2009) = 0.51, and a photovoltaic-biased photoelectrochemical ideal regenerative cell efficiency of 0.6%.", "date": "2016", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "163", "number": "5", "publisher": "Electrochemical Society", "pagerange": "H261-H264", "id_number": "CaltechAUTHORS:20160301-075443518", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160301-075443518", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1149/2.0141605jes", "primary_object": { "basename": "J._Electrochem._Soc.-2016-Shaner-H261-4.pdf", "url": "https://authors.library.caltech.edu/records/k3tyh-n2h33/files/J._Electrochem._Soc.-2016-Shaner-H261-4.pdf" }, "related_objects": [ { "basename": "README.txt", "url": "https://authors.library.caltech.edu/records/k3tyh-n2h33/files/README.txt" } ], "pub_year": "2016", "author_list": "Shaner, Matthew R.; McDowell, Matthew T.; et el." }, { "id": "https://authors.library.caltech.edu/records/kbrw5-0dq72", "eprint_id": 62955, "eprint_status": "archive", "datestamp": "2023-08-20 09:33:56", "lastmod": "2023-10-25 22:58:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Axnanda-S", "name": { "family": "Axnanda", "given": "Stephanus" } }, { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter" }, "orcid": "0000-0002-8693-4562" }, { "id": "Hussain-Z", "name": { "family": "Hussain", "given": "Zahid" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Liu-Zhi", "name": { "family": "Liu", "given": "Zhi" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "An Electrochemical, Microtopographical and Ambient Pressure X-Ray Photoelectron Spectroscopic Investigation of Si/TiO_2/Ni/Electrolyte Interfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Author(s). Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. \n\nManuscript submitted September 9, 2015; revised manuscript received November 16, 2015. Published December 5, 2015. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE AC02 05CH11231. We thank Dr. Philip Ross for contributions to the conceptual development of the AP-XPS end station and experimental design.\n\nPublished - J._Electrochem._Soc.-2016-Lichterman-H139-46.pdf
", "abstract": "The electrical and spectroscopic properties of the TiO_2/Ni protection layer system, which enables stabilization of otherwise corroding photoanodes, have been investigated in contact with electrolyte solutions by scanning-probe microscopy, electrochemistry and in-situ ambient pressure X-ray photoelectron spectroscopy (AP-XPS). Specifically, the energy-band relations of the p+-Si/ALD-TiO_2/Ni interface have been determined for a selected range of Ni thicknesses. AP-XPS measurements using tender X-rays were performed in a three-electrode electrochemical arrangement under potentiostatic control to obtain information from the semiconductor near-surface region, the electrochemical double layer (ECDL) and the electrolyte beyond the ECDL. The degree of conductivity depended on the chemical state of the Ni on the TiO2surface. At low loadings of Ni, the Ni was present primarily as an oxide layer and the samples were not conductive, although the TiO_2 XPS core levels nonetheless displayed behavior indicative of a metal-electrolyte junction. In contrast, as the Ni thickness increased, the Ni phase was primarily metallic and the electrochemical behavior became highly conductive, with the AP-XPS data indicative of a metal-electrolyte junction. Electrochemical and microtopographical methods have been employed to better define the nature of the TiO_2/Ni electrodes and to contextualize the AP-XPS results.", "date": "2016", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "163", "number": "2", "publisher": "Electrochemical Society", "pagerange": "H139-H146", "id_number": "CaltechAUTHORS:20151215-152721755", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151215-152721755", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.0861602jes", "primary_object": { "basename": "J._Electrochem._Soc.-2016-Lichterman-H139-46.pdf", "url": "https://authors.library.caltech.edu/records/kbrw5-0dq72/files/J._Electrochem._Soc.-2016-Lichterman-H139-46.pdf" }, "pub_year": "2016", "author_list": "Lichterman, Michael F.; Richter, Matthias H.; et el." }, { "id": "https://authors.library.caltech.edu/records/tx8me-tva37", "eprint_id": 61780, "eprint_status": "archive", "datestamp": "2023-08-20 09:26:59", "lastmod": "2023-10-25 15:44:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ping-Yuan", "name": { "family": "Ping", "given": "Yuan" } }, { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Solvation effects on the band edge positions of photocatalysts from first principles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 the Owner Societies. This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. \n\nReceived 24th September 2015, Accepted 26th October 2015, First published online 26 Oct 2015. \n\nWe thank Giulia Galli and Tuan Anh Pham for many useful discussions. This publication is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DESC0004993.\n\nPublished - Solvation_effects_on_the_band_edge_positions_of_photocatalysts_from_first_principles.pdf
", "abstract": "The band edge positions of photocatalysts relative to the redox potentials of water play an important role in determining the efficiency of photoelectrochemical cells. These band positions depend on the structure of the solid\u2013liquid interface, but direct ab initio molecular dynamics calculations of these interfaces, while expected to be accurate, are too computationally demanding for high-throughput materials screening. Thus rapid theoretical screening of new photocatalyst materials requires simplified continuum solvation models that are suitable for treating solid\u2013liquid interfaces. In this paper, we evaluate the accuracy of the recently developed CANDLE and SaLSA continuum solvation models for predicting solvation effects on the band positions of several well-studied surfaces [Si(111), TiO_2(110), IrO_2(110) and WO_3(001)] in water. We find that the solvation effects vary considerably, ranging from <0.5 eV for hydrophobic surfaces, 0.5\u20131 eV for many hydrophilic oxide surfaces, to \u223c2 eV for oxygen-deficient surfaces. The solvation model predictions are in excellent agreement (within \u223c0.1 eV) with ab initio molecular dynamics results where available, and in good agreement (within \u223c0.2\u20130.3 eV) with experimental measurements. We also predict the energetics for surface oxygen vacancies and their effect on the band positions of the hydrated WO_3(001) surface, leading to an explanation for why the solvation shift observed experimentally is substantially larger than predicted for the ideal surface. Based on the correlation between solvation shift and the type of surface and solvent, we suggest approaches to engineer the band positions of surfaces in aqueous and non-aqueous solutions.", "date": "2015-12-07", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "17", "number": "45", "publisher": "Royal Society of Chemistry", "pagerange": "30499-30509", "id_number": "CaltechAUTHORS:20151103-075722264", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151103-075722264", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1146", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5cp05740j", "primary_object": { "basename": "Solvation_effects_on_the_band_edge_positions_of_photocatalysts_from_first_principles.pdf", "url": "https://authors.library.caltech.edu/records/tx8me-tva37/files/Solvation_effects_on_the_band_edge_positions_of_photocatalysts_from_first_principles.pdf" }, "pub_year": "2015", "author_list": "Ping, Yuan; Sundararaman, Ravishankar; et el." }, { "id": "https://authors.library.caltech.edu/records/k6q5j-d7r47", "eprint_id": 62330, "eprint_status": "archive", "datestamp": "2023-08-22 17:01:10", "lastmod": "2023-10-25 17:03:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Cheng-Tao", "name": { "family": "Cheng", "given": "Tao" }, "orcid": "0000-0003-4830-177X" }, { "id": "Xiao-Hai", "name": { "family": "Xiao", "given": "Hai" }, "orcid": "0000-0001-9399-1584" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "Free-Energy Barriers and Reaction Mechanisms for the Electrochemical Reduction of CO on the Cu(100) Surface, Including Multiple Layers of Explicit Solvent at pH 0", "ispublished": "pub", "full_text_status": "public", "keywords": "interface; electrochemistry; CO2 reduction; quantum molecular dynamics; density functional theory; PBE; metadynamics; constrained molecular dynamics; free energy; green chemistry", "note": "\u00a9 2015 American Chemical Society. This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: October 8, 2015; Accepted: November 12, 2015; Published: November 12, 2015. \n\nThis work was initiated with support from National Science Foundation (CHE 1512759 and completed with support by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. We thank Dr. Robert J. Nielsen, Dr. Manny Soriaga, and Ms. Yufeng Huang for helpful discussions. \n\nThe authors declare no competing financial interest.\n\nPublished - acs.jpclett.5b02247.pdf
Supplemental Material - jz5b02247_si_001.pdf
", "abstract": "The great interest in the photochemical reduction from CO_2 to fuels and chemicals has focused attention on Cu because of its unique ability to catalyze formation of carbon-containing fuels and chemicals. A particular goal is to learn how to modify the Cu catalysts to enhance the production selectivity while reducing the energy requirements (overpotential). To enable such developments, we report here the free-energy reaction barriers and mechanistic pathways on the Cu(100) surface, which produces only CH_4 (not C_2H_4 or CH_3OH) in acid (pH 0). We predict a threshold potential for CH_4 formation of \u22120.52 V, which compares well to experiments at low pH, \u22120.45 to \u22120.50 V. These quantum molecular dynamics simulations included \u223c5 layers of explicit water at the water/electrode interface using enhanced sampling methodology to obtain the free energies. We find that that chemisorbed hydroxyl-methylene (CH\u2013OH) is the key intermediate determining the selectivity for methane over methanol.", "date": "2015-12-03", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "6", "number": "23", "publisher": "American Chemical Society", "pagerange": "4767-4773", "id_number": "CaltechAUTHORS:20151123-110728006", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151123-110728006", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1512759" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1145", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpclett.5b02247", "primary_object": { "basename": "acs.jpclett.5b02247.pdf", "url": "https://authors.library.caltech.edu/records/k6q5j-d7r47/files/acs.jpclett.5b02247.pdf" }, "related_objects": [ { "basename": "jz5b02247_si_001.pdf", "url": "https://authors.library.caltech.edu/records/k6q5j-d7r47/files/jz5b02247_si_001.pdf" } ], "pub_year": "2015", "author_list": "Cheng, Tao; Xiao, Hai; et el." }, { "id": "https://authors.library.caltech.edu/records/9v784-4va95", "eprint_id": 62753, "eprint_status": "archive", "datestamp": "2023-08-20 09:14:28", "lastmod": "2023-10-25 17:22:39", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Jiang-Jingjing", "name": { "family": "Jiang", "given": "Jingjing" } }, { "id": "Hua-Yueming", "name": { "family": "Hua", "given": "Yueming" } }, { "id": "Li-Chunzeng", "name": { "family": "Li", "given": "Chunzeng" } }, { "id": "Wagner-M", "name": { "family": "Wagner", "given": "Martin" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Anfuso-C", "name": { "family": "Anfuso", "given": "Chantelle" } } ] }, "title": "Atomic Force Microscopy for Solar Fuels Research: An Introductory Review", "ispublished": "pub", "full_text_status": "restricted", "keywords": "AFM, Solar Fuel, Nano Electricity, Nano Mechanics, S-SNOM, In Situ Characterization", "note": "\u00a9 2015 American Scientific Publishers. \n\nReceived: 2 March 2015; Accepted: 3 April 2015. \n\nZhuangqun Huang and Jingjing Jiang acknowledge support from the Beckman Institute of the California Institute of Technology to the Molecular Materials Research Center. JJ, HJL and MPS acknowledge the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993. ZH acknowledges the support from the National Natural Science Foundation of China (Grant No. 21376020) and Sanyuan Ceramics Limited (Group of Company) Chaozhou, China, in particular the support from Dr. Zaiyuan Huang and Dr. Xiaodong Huang.", "abstract": "Although research on solar fuel production via water oxidation, hydrogen evolution, and carbon dioxide reduction (i.e., artificial photosynthesis) has grown tremendously in recent years, practical solar fuel devices remain elusive. For these multi-electron transfer processes to take place efficiently, integrated systems constructed from materials with very different chemical, mechanical, and electrical properties are required. This complicated integration presents numerous challenges, including the need for increased characterization of material surfaces and interfaces for both fundamental studies and device optimization. Atomic force microscopy (AFM) is a powerful tool for surface and interface analysis. Although solar fuel research has frequently utilized the basic AFM function of topographic mapping for routine surface analysis, some researchers have avoided more advanced AFM methodologies due to the complexity of these integrated solar fuel generating systems. This article provides researchers in this area with an introduction to various advanced AFM techniques for mechanical, electrical, and chemical analysis on the nanoscale. It also discusses the possibility of in situ study while providing an outline of the working principles of different AFM application modes.", "date": "2015-12", "date_type": "published", "publication": "Energy and Environment Focus", "volume": "4", "number": "4", "publisher": "American Scientific Publishers", "pagerange": "260-277", "id_number": "CaltechAUTHORS:20151209-134832901", "issn": "2326-3040", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151209-134832901", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech Beckman Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21376020" }, { "agency": "Sanyuan Ceramics Limited" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1166/eef.2015.1180", "pub_year": "2015", "author_list": "Huang, Zhuangqun; Jiang, Jingjing; et el." }, { "id": "https://authors.library.caltech.edu/records/h78s1-9tk69", "eprint_id": 60981, "eprint_status": "archive", "datestamp": "2023-08-22 16:53:55", "lastmod": "2023-10-24 22:34:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gethers-M-L", "name": { "family": "Gethers", "given": "Matthew L." } }, { "id": "Thomas-J-C", "name": { "family": "Thomas", "given": "John C." } }, { "id": "Jiang-Shan", "name": { "family": "Jiang", "given": "Shan" } }, { "id": "Weiss-N-O", "name": { "family": "Weiss", "given": "Nathan O." } }, { "id": "Duan-Xiangfang", "name": { "family": "Duan", "given": "Xiangfang" } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A." }, "orcid": "0000-0003-0097-5716" }, { "id": "Weiss-P-S", "name": { "family": "Weiss", "given": "Paul S." } } ] }, "title": "Holey Graphene as a Weed Barrier for Molecules", "ispublished": "pub", "full_text_status": "public", "keywords": "nanoscience; graphene; mask; chemical patterning; self-assembly; scanning tunneling microscopy", "note": "\u00a9 2015 American Chemical Society. \n\nReceived for review June 27, 2015, and accepted October 1, 2015. Publication Date (Web): October 1, 2015. \n\nWe thank the Department of Energy Grant #DE-SC-0005025 for support of the instrumentation and methods developed and applied here. Partial support was provided by NSF Grant #ODISSEI-EFRI-1332411 and the Caltech EAS Discovery Fund (M.G. and W.A.G.). We also thank the NSF (Grant #EFRI-1433541) for support (X.F.D., S.J., and N.O.W.). J.C.T. acknowledges support from an excellence in chemistry graduate research fellowship from UCLA. P.S.W. acknowledges support from the Caltech Kavli Nanoscience Institute and Joint Center for Artificial Photosynthesis. We gratefully thank Jeffrey J. Schwartz, Ivo Atanasov, and Chih-Yen Chen for helpful discussions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - nn5b03936_si_001.pdf
", "abstract": "We demonstrate the use of \"holey\" graphene as a mask against molecular adsorption. Prepared porous graphene is transferred onto a Au{111} substrate, annealed, and then exposed to dilute solutions of 1-adamantanethiol. In the pores of the graphene lattice, we find islands of organized, self-assembled molecules. The bare Au in the pores can be regenerated by postdeposition annealing, and new molecules can be self-assembled in the exposed Au region. Graphene can serve as a robust, patternable mask against the deposition of self-assembled monolayers.", "date": "2015-11-24", "date_type": "published", "publication": "ACS Nano", "volume": "9", "number": "11", "publisher": "American Chemical Society", "pagerange": "10909-10915", "id_number": "CaltechAUTHORS:20151012-132204304", "issn": "1936-0851", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151012-132204304", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC-0005025" }, { "agency": "NSF", "grant_number": "ODISSEI-EFRI-1332411" }, { "agency": "Caltech EAS Discovery Fund" }, { "agency": "NSF", "grant_number": "EFRI-1433541" }, { "agency": "UCLA" }, { "agency": "Kavli Nanoscience Institute" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "other_numbering_system": { "items": [ { "id": "1147", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acsnano.5b03936", "primary_object": { "basename": "nn5b03936_si_001.pdf", "url": "https://authors.library.caltech.edu/records/h78s1-9tk69/files/nn5b03936_si_001.pdf" }, "pub_year": "2015", "author_list": "Gethers, Matthew L.; Thomas, John C.; et el." }, { "id": "https://authors.library.caltech.edu/records/yfxvs-dk106", "eprint_id": 60033, "eprint_status": "archive", "datestamp": "2023-08-22 16:52:30", "lastmod": "2023-10-24 14:49:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Becerra-Stasiewicz-N", "name": { "family": "Becerra-Stasiewicz", "given": "Natalie" } }, { "id": "Chatman-S-M", "name": { "family": "Chatman", "given": "Shawn M." }, "orcid": "0000-0002-7951-5968" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High Throughput Discovery of Solar Fuels Photoanodes in the CuO-V_2O_5 System", "ispublished": "pub", "full_text_status": "public", "keywords": "copper vanadate; density functional theory calculations; high throughput experimentation; photo-electrochemistry; solar fuels", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: May 15, 2015;\nRevised: July 19, 2015;\nArticle first published online: 26 Aug 2015.\nThis manuscript is based upon work performed by the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of Energy\n(Award No. DE-SC0004993). Computational work was supported by\nthe Materials Project Predictive Modeling Center (EDCBEE) through\nthe U.S. Department of Energy, Office of Basic Energy Sciences,\nMaterials Sciences and Engineering Division, under Contract No.\nDE-AC02-05CH11231. Work at the Molecular Foundry was supported\nby the Office of Science, Office of Basic Energy Sciences, of the U.S.\nDepartment of Energy under Contract No. DE-AC02\u201305CH11231.\nThe authors thank F. M. Toma and I. D. Sharp for preparation of the\nBiVO_4 electrodes and H. J. Lewerenz and H. A. Atwater for illuminating\ndiscussions.\n\nSupplemental Material - aenm201500968-sup-0001-S1.pdf
", "abstract": "Solar photoelectrochemical generation of fuel is a promising energy technology yet the lack of an efficient, robust photoanode remains a primary materials challenge in the development and deployment of solar fuels generators. Metal oxides comprise the most promising class of photoanode materials, but no known material meets the demanding requirements of low band gap energy, photoelectrocatalysis of the oxygen evolution reaction (OER), and stability under highly oxidizing conditions. Here, the identification of new photoelectroactive materials is reported through a strategic combination of combinatorial materials synthesis, high-throughput photoelectrochemistry, optical spectroscopy, and detailed electronic structure calculations. Four photoelectrocatalyst phases, \u03b1-Cu_2V_2O_7, \u03b2-Cu_2V_2O_7,\u03b3-Cu_3V_2O_8, and Cu_(11)V_6O_(26), are reported with band gap energy at or below 2 eV. The photoelectrochemical properties and 30 min stability of these copper vanadate phases are demonstrated in three different aqueous electrolytes (pH 7, pH 9, and pH 13), with select combinations of phase and electrolyte exhibiting unprecedented photoelectrocatalytic stability for metal oxides with sub-2 eV band gap. Through integration of experimental and theoretical techniques, new structure-property relationships are determined and establish CuO\u2013V_2O_5 as the most prominent composition system for OER photoelectrocatalysts, providing crucial information for materials genomes initiatives and paving the way for continued development of solar fuels photoanodes.", "date": "2015-11-18", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "5", "number": "22", "publisher": "Wiley", "pagerange": "Art. No. 1500968", "id_number": "CaltechAUTHORS:20150902-125617374", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150902-125617374", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201500968", "primary_object": { "basename": "aenm201500968-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/yfxvs-dk106/files/aenm201500968-sup-0001-S1.pdf" }, "pub_year": "2015", "author_list": "Zhou, Lan; Yan, Qimin; et el." }, { "id": "https://authors.library.caltech.edu/records/rc1cc-r8722", "eprint_id": 59897, "eprint_status": "archive", "datestamp": "2023-08-20 08:58:46", "lastmod": "2023-10-23 22:48:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan" }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A., Jr." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "A Monolithically Integrated, Intrinsically Safe, 10% Efficient, Solar-Driven Water-Splitting System Based on Active, Stable Earth-Abundant Electrocatalysts in Conjunction with Tandem III-V Light Absorbers Protected by Amorphous TiO_2 Films", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Royal Society of Chemistry. \n\nReceived 09 Jun 2015, Accepted 17 Aug 2015, First published online 18 Aug 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. This work was additionally supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225.\n\nPublished - c5ee01786f.pdf
Supplemental Material - c5ee01786f1.pdf
Supplemental Material - c5ee01786f2.mp4
", "abstract": "A monolithically integrated device consisting of a tandem-junction GaAs/InGaP photoanode coated by an amorphous TiO_2 stabilization layer, in conjunction with Ni-based, earth-abundant active electrocatalysts for the hydrogen-evolution and oxygen-evolution reactions, was used to effect unassisted, solar-driven water splitting in 1.0 M KOH(aq). When connected to a Ni-Mo-coated counterelectrode in a two-electrode cell configuration, the TiO_2-protected III-V tandem device exhibited a solar-to-hydrogen conversion efficiency, \u03b7_(STH), of 10.5% under 1 sun illumination, with stable performance for > 40 h of continuous operation at an efficiency of \u03b7_(STH) >10%. The protected tandem device also formed the basis for a monolithically integrated, intrinsically safe solar-hydrogen prototype system (1 cm^2) driven by a NiMo/GaAs/InGaP/TiO_2/Ni structure. The intrinsically safe system exhibited a hydrogen production rate of 0.81 \u03bcL s^(-1) and a solar-to-hydrogen conversion efficiency of 8.6% under 1 sun illumination in 1.0 M KOH(aq), with minimal product gas crossover while allowing for beneficial collection of separate streams of H_2(g) and O_2(g).", "date": "2015-11-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "11", "publisher": "Royal Society of Chemistry", "pagerange": "3166-3172", "id_number": "CaltechAUTHORS:20150825-164619530", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150825-164619530", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C5EE01786F", "primary_object": { "basename": "c5ee01786f.pdf", "url": "https://authors.library.caltech.edu/records/rc1cc-r8722/files/c5ee01786f.pdf" }, "related_objects": [ { "basename": "c5ee01786f1.pdf", "url": "https://authors.library.caltech.edu/records/rc1cc-r8722/files/c5ee01786f1.pdf" }, { "basename": "c5ee01786f2.mp4", "url": "https://authors.library.caltech.edu/records/rc1cc-r8722/files/c5ee01786f2.mp4" } ], "pub_year": "2015", "author_list": "Verlage, Erik; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/sp7w7-fsd97", "eprint_id": 59977, "eprint_status": "archive", "datestamp": "2023-08-20 08:50:23", "lastmod": "2023-10-24 14:47:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Overlayer Au-on-W Near-Surface Alloy for the Selective Electrochemical Reduction of CO_2 to Methanol: Empirical (DEMS) Corroboration of a Computational (DFT) Prediction", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 Springer Science+Business Media New York. \n\nFirst online: 27 August 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "It is now widely known from extensive studies [1\u20133] over the past few decades on the heterogeneous electrochemical reduction of carbon dioxide in aqueous solutions that, across the vast landscape of CO_2-reduction electrocatalysts, copper stands alone as the single metal that can deliver a remarkable variety of products; unpredictably, however, the product distribution does not include methanol [1\u20135]. The overall energy conversion efficiency of Cu, defined [6] as the ratio of the free energy of the products generated and that consumed in the electrochemical reduction, is only 30 to 40 %, and the overpotential of Cu at benchmark current densities remains unacceptably large, ca. \u22121.4 V [1, 6]. The diversity of the product distribution also becomes a major hurdle if only one product is coveted. The desire for catalysts that can perform better than Cu, especially in the generation of methanol, a liquid transportation fuel, and feedstock for direct fuel cells, is thus understandable.", "date": "2015-11", "date_type": "published", "publication": "Electrocatalysis", "volume": "6", "number": "6", "publisher": "Springer", "pagerange": "493-497", "id_number": "CaltechAUTHORS:20150831-084011671", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150831-084011671", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-015-0276-8", "pub_year": "2015", "author_list": "Javier, Alnald; Baricuatro, Jack H.; et el." }, { "id": "https://authors.library.caltech.edu/records/6k144-ras44", "eprint_id": 57216, "eprint_status": "archive", "datestamp": "2023-08-20 08:49:35", "lastmod": "2023-10-23 17:10:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fenwick-A-Q", "name": { "family": "Fenwick", "given": "Aidan Q." }, "orcid": "0000-0003-4442-0878" }, { "id": "Luca-O-R", "name": { "family": "Luca", "given": "Oana R." }, "orcid": "0000-0002-2988-4909" } ] }, "title": "The Formation of CO by Thermal Decomposition of Formic Acid under Electrochemical Conditions of CO_2 Reduction", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 Elsevier B.V. \n\nReceived 6 December 2014; Received in revised form 23 March 2015; Accepted 1 April 2015; Available online 22 April 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.", "abstract": "We report that the thermal decomposition of formic acid to CO may occur under electrochemically-relevant conditions by mild heating. These thermal effects may play a role in the outcome of electrolytic experiments as an artifact of resistive, local heating and illumination. This non-Faradaic reactivity pathway may therefore need consideration in the analysis of electrochemical data on CO_2 reduction to formic acid and CO and may become a hindrance in scaleup efforts of these chemical transformations. IR visual thermometry provides evidence of macroscopic heating effects during electrolytic experiments.", "date": "2015-11", "date_type": "published", "publication": "Journal of Photochemistry and Photobiology B: Biology", "volume": "152", "publisher": "Elsevier", "pagerange": "43-46", "id_number": "CaltechAUTHORS:20150505-082908999", "issn": "1011-1344", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150505-082908999", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jphotobiol.2015.04.003", "pub_year": "2015", "author_list": "Fenwick, Aidan Q. and Luca, Oana R." }, { "id": "https://authors.library.caltech.edu/records/2a6j9-aqm43", "eprint_id": 63324, "eprint_status": "archive", "datestamp": "2023-08-20 08:55:07", "lastmod": "2023-10-25 23:43:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fenwick-A-Q", "name": { "family": "Fenwick", "given": "Aidan Q." }, "orcid": "0000-0003-4442-0878" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Luca-O-R", "name": { "family": "Luca", "given": "Oana R." }, "orcid": "0000-0002-2988-4909" } ] }, "title": "Electrocatalytic Reduction of Nitrogen and Carbon Dioxide to Chemical Fuels: Challenges and Opportunities for a Solar Fuel Device", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2016 Elsevier B.V.", "abstract": "Aspects of the electrochemical reduction of nitrogen and carbon dioxide at molecular and heterogeneous catalysts are discussed. We focus on recent advances in the field and touch on some of the remaining challenges in the production of solar fuels from N_2 and CO_2 with a direct, integrated solar fuel device. As such, we now propose metrics of catalyst assessment for non-H_2 solar fuels.", "date": "2015-11", "date_type": "published", "publication": "Journal of Photochemistry and Photobiology B: Biology", "volume": "152", "publisher": "Elsevier", "pagerange": "47-57", "id_number": "CaltechAUTHORS:20160104-105432412", "issn": "1011-1344", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160104-105432412", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jphotobiol.2014.12.019", "pub_year": "2015", "author_list": "Fenwick, Aidan Q.; Gregoire, John M.; et el." }, { "id": "https://authors.library.caltech.edu/records/g9c0k-d0w98", "eprint_id": 61557, "eprint_status": "archive", "datestamp": "2023-08-20 08:47:52", "lastmod": "2023-10-25 15:00:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Ager-J-W", "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" }, { "id": "Yang-Jinhui", "name": { "family": "Yang", "given": "Jinhui" } }, { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Strandwitz-N-C", "name": { "family": "Strandwitz", "given": "Nicholas C." } } ] }, "title": "Thin-Film Materials for the Protection of Semiconducting Photoelectrodes in Solar-Fuel Generators", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: June 22, 2015. Revised: September 25, 2015. Publication Date (Web): September 28, 2015. \n\nNCS acknowledges start-up funds from Lehigh University. JRM acknowledges a postdoctoral research award from the U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy through the SunShot Initiative. SH, NSL, JWA, and JY were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, and NSL was also supported by the National Science Foundation under Award Number CHE-1214152, the Department of Energy, Office of Basic Energy Sciences under Award Number DE-FG02-03ER15483, and the Gordon and Betty Moore Foundation under Award Number GBMF1225. \n\nThe authors declare no competing financial interest.", "abstract": "The electrochemical instability of semiconductors in aqueous electrolytes has impeded the development of robust sunlight-driven water-splitting systems. We review the use of protective thin films to improve the electrochemical stability of otherwise unstable semiconductor photoelectrodes (e.g., Si and GaAs). We first discuss the origins of instability and various strategies for achieving stable and functional photoelectrosynthetic interfaces. We then focus specifically on the use of thin protective films on photoanodes and photocathodes for photosynthetic reactions that include oxygen evolution, halide oxidation, and hydrogen evolution. Finally, we provide an outlook for the future development of thin-layer protection strategies to enable semiconductor-based solar-driven fuel production.", "date": "2015-10-29", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "119", "number": "43", "publisher": "American Chemical Society", "pagerange": "24201-24228", "id_number": "CaltechAUTHORS:20151027-111752059", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151027-111752059", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Lehigh University" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.5b05976", "pub_year": "2015", "author_list": "Hu, Shu; Lewis, Nathan S.; et el." }, { "id": "https://authors.library.caltech.edu/records/v1g0w-1s033", "eprint_id": 61242, "eprint_status": "archive", "datestamp": "2023-08-22 16:40:22", "lastmod": "2023-10-25 14:39:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Becerra-Stasiewicz-N", "name": { "family": "Becerra-Stasiewicz", "given": "Natalie" } }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combining reactive sputtering and rapid thermal processing for synthesis and discovery of metal oxynitrides", "ispublished": "pub", "full_text_status": "public", "keywords": "oxynitrides; sputtering; rapid thermal processing; mixed anion synthesis", "note": "\u00a9 2015 Materials Research Society. \n\nReceived 15 February 2015; accepted 28 April 2015. Published online: 27 May 2015. \n\nThis study is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DESC0004993). The authors thank the Kurt J. Lesker company for assistance with the design of the custom PVD gas handling system.\n\nPublished - JMR-JMR30_19-S0884291415001405a.pdf
Supplemental Material - S0884291415001405sup001.pdf
", "abstract": "Recent efforts have demonstrated enhanced tailoring of material functionality with mixed anion materials, yet exploratory research with mixed anion chemistries is limited by the sensitivity of these materials to synthesis conditions. Synthesis of a particular metal oxynitride compound by traditional reactive annealing requires specific, limited ranges of both oxygen and nitrogen chemical potentials to establish equilibrium between the solid-state material and a reactive atmosphere. Using Ta\u2013O\u2013N as an example system, we describe a combination of reactive sputter deposition and rapid thermal processing (RTP) for synthesis of mixed anion inorganic materials. Heuristic optimization of reactive gas pressures to attain a desired anion stoichiometry is discussed, and the ability of RTP to enable amorphous to crystalline transitions without preferential anion loss is demonstrated through the controlled synthesis of nitride, oxide, and oxynitride phases.", "date": "2015-10-14", "date_type": "published", "publication": "Journal of Materials Research", "volume": "30", "number": "19", "publisher": "Materials Research Society", "pagerange": "2928-2933", "id_number": "CaltechAUTHORS:20151019-090734492", "issn": "0884-2914", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151019-090734492", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1557/jmr.2015.140", "primary_object": { "basename": "JMR-JMR30_19-S0884291415001405a.pdf", "url": "https://authors.library.caltech.edu/records/v1g0w-1s033/files/JMR-JMR30_19-S0884291415001405a.pdf" }, "related_objects": [ { "basename": "S0884291415001405sup001.pdf", "url": "https://authors.library.caltech.edu/records/v1g0w-1s033/files/S0884291415001405sup001.pdf" } ], "pub_year": "2015", "author_list": "Zhou, Lan; Suram, Santosh K.; et el." }, { "id": "https://authors.library.caltech.edu/records/zjvhw-mb970", "eprint_id": 61715, "eprint_status": "archive", "datestamp": "2023-08-20 08:30:59", "lastmod": "2023-10-25 15:40:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ager-J-W", "name": { "family": "Ager", "given": "Joel W." }, "orcid": "0000-0001-9334-9751" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Walczak-K-A", "name": { "family": "Walczak", "given": "Karl A." } }, { "id": "Sharp-I-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" } ] }, "title": "Experimental demonstrations of spontaneous, solar-driven photoelectrochemical water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. \n\nReceived 10 Feb 2015, Accepted 24 Mar 2015; First published online 24 Mar 2015. \n\nThe authors thank Dr Eric Miller for the inspiration to compile this review, and the members of the U.S. Department of Energy's Photoelectrochemical Working Group and Task 35 (Renewable Hydrogen) of the International Energy Agency's Hydrogen Implementing Agreement for helpful comments, suggestions, and discussions, especially Heli Wang, Keith Emery, and Tom Jaramillo. JWA, KAW, IDS, and MS were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. SA acknowledges support from the Department of Chemistry and the School of Physical Sciences at the University of California, Irvine. MS acknowledges the Resnick Institute for Sustainability for a graduate fellowship. A summary version of this review paper (DOI: 10.2172/1209500) can be found on the working group website http://energy.gov/eere/fuelcells/photoelectrochemicalworking-group). The STH efficiency tables and graph will be updated as the field progresses.\n\nPublished - c5ee00457h.pdf
Supplemental Material - c5ee00457h1_si.pdf
", "abstract": "Laboratory demonstrations of spontaneous photoelectrochemical (PEC) solar water splitting cells are reviewed. Reported solar-to-hydrogen (STH) conversion efficiencies range from <1% to 18%. The demonstrations are categorized by the number of photovoltaic junctions employed (2 or 3), photovoltaic junction type (solid\u2013solid or solid\u2013liquid) and the ability of the systems to produce separated reaction product streams. Demonstrations employing two photovoltaic (PV) junctions have the highest reported efficiencies of 12.4% and 18%, which are for cells that, respectively, do and do not contain a semiconductor\u2013liquid junction. These devices used PV components based on III\u2013V semiconductors; recently, a number of demonstrations with >10% STH efficiency using potentially less costly materials have been reported. Device stability is a major challenge for the field, as evidenced by lifetimes of less than 24 hours in all but a few reports. No globally accepted protocol for evaluating and certifying STH efficiencies and lifetimes exists. It is our recommendation that a protocol similar to that used by the photovoltaic community be adopted so that future demonstrations of solar PEC water splitting can be compared on equal grounds.", "date": "2015-10-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2811-2824", "id_number": "CaltechAUTHORS:20151029-125838701", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151029-125838701", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of California, Irvine" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c5ee00457h", "primary_object": { "basename": "c5ee00457h.pdf", "url": "https://authors.library.caltech.edu/records/zjvhw-mb970/files/c5ee00457h.pdf" }, "related_objects": [ { "basename": "c5ee00457h1_si.pdf", "url": "https://authors.library.caltech.edu/records/zjvhw-mb970/files/c5ee00457h1_si.pdf" } ], "pub_year": "2015", "author_list": "Ager, Joel W.; Shaner, Matthew R.; et el." }, { "id": "https://authors.library.caltech.edu/records/y51kf-4xb27", "eprint_id": 59572, "eprint_status": "archive", "datestamp": "2023-08-20 08:20:37", "lastmod": "2023-10-23 20:44:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Functional integration of Ni\u2013Mo electrocatalysts with Si microwire array photocathodes to simultaneously achieve high fill factors and light-limited photocurrent densities for solar-driven hydrogen evolution", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2015.\n\nReceived 05 Apr 2015, Accepted 13 Jul 2015; First published online 07 Aug 2015. \n\nThis article is part of themed collection: Fundamentals and Applications of Inorganic Chemistry.\n\nDevice modeling, fabrication and testing were supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub supported through the Office of Science of the U.S. Department of Energy under award number DE-SC004993. Development of the Ni\u2013Mo nanopowder catalyst was supported by the National Science Foundation (NSF) Powering the Planet Center for Chemical Innovation (CHE-1305124) and by the Molecular Materials Research Center of the Beckman Institute at the California Institute of Technology. The authors acknowledge additional support by the Gordon and Betty Moore Foundation (GBMF1225). MRS acknowledges the Resnick Sustainability Institute for a graduate fellowship. JRM acknowledges the Department of Energy, Office of Science, for a graduate research fellowship and the Department of Energy, Office of Energy Efficiency and Renewable Energy, for a SunShot postdoctoral research award.\n\nPublished - c5ee01076d.pdf
Supplemental Material - suppc5ee01076d1.pdf
", "abstract": "An n+p-Si microwire array coupled with a two-layer catalyst film consisting of Ni\u2013Mo nanopowder and TiO_2 light-scattering nanoparticles has been used to simultaneously achieve high fill factors and light-limited photocurrent densities from photocathodes that produce H_2(g) directly from sunlight and water. The TiO_2 layer scattered light back into the Si microwire array, while optically obscuring the underlying Ni\u2013Mo catalyst film. In turn, the Ni\u2013Mo film had a mass loading sufficient to produce high catalytic activity, on a geometric area basis, for the hydrogen-evolution reaction. The best-performing microwire array devices prepared in this work exhibited short-circuit photocurrent densities of \u221214.3 mA cm^(\u22122), photovoltages of 420 mV, and a fill factor of 0.48 under 1 Sun of simulated solar illumination, whereas the equivalent planar Ni\u2013Mo-coated Si device, without TiO_2 scatterers, exhibited negligible photocurrent due to complete light blocking by the Ni\u2013Mo catalyst layer.", "date": "2015-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2977-2984", "id_number": "CaltechAUTHORS:20150814-170845573", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150814-170845573", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC004993" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "1225" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C5EE01076D", "primary_object": { "basename": "c5ee01076d.pdf", "url": "https://authors.library.caltech.edu/records/y51kf-4xb27/files/c5ee01076d.pdf" }, "related_objects": [ { "basename": "suppc5ee01076d1.pdf", "url": "https://authors.library.caltech.edu/records/y51kf-4xb27/files/suppc5ee01076d1.pdf" } ], "pub_year": "2015", "author_list": "Shaner, Matthew R.; McKone, James R.; et el." }, { "id": "https://authors.library.caltech.edu/records/64cr5-dje08", "eprint_id": 61744, "eprint_status": "archive", "datestamp": "2023-08-20 08:23:03", "lastmod": "2023-10-25 15:41:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fabian-D-M", "name": { "family": "Fabian", "given": "David M." } }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Singh-N", "name": { "family": "Singh", "given": "Nirala" } }, { "id": "Houle-F-A", "name": { "family": "Houle", "given": "Frances A." }, "orcid": "0000-0001-5571-2548" }, { "id": "Hisatomi-Takashi", "name": { "family": "Hisatomi", "given": "Takashi" } }, { "id": "Domen-Kazunari", "name": { "family": "Domen", "given": "Kazunari" } }, { "id": "Osterloh-F-E", "name": { "family": "Osterloh", "given": "Frank E." } }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" } ] }, "title": "Particle suspension reactors and materials for solar-driven water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Royal Society of Chemistry. \n\nReceived 8th May 2015, Accepted 13th July 2015. \n\nThe authors thank Dr. Eric Miller for the inspiration to compile this review, and the members of the U.S. Department of Energy's Photoelectrochemical Working Group and Task 35 (Renewable Hydrogen) of the International Energy Agency's Hydrogen Implementing Agreement for helpful comments, suggestions, and discussions, specifically Prof. Ryu Abe (Kyoto University), Prof. Jason Baxter (Drexel University), Prof. Jiming Bao (University of Houston), Prof. Dan Esposito (Columbia University), Dr. Arnold Forman (Bio-Logic), Prof. Sophia Haussener (\u00c9cole polytechnique f\u00e9d\u00e9rale de Lausanne), Prof. Akihiko Kudo (Tokyo University of Science), Dr. Kazuhiko Maeda (Tokyo Institute of Technology), Dr. Sixto Malato (Plataforma Solar de Almer\u00eda), Dr. Steve Reece (Sun Catalytix), and Prof. Wilson Smith (Delft University of Technology). D.M.F. acknowledges support by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1321846. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: work by S.H. and F.A.H. was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. N.S. is supported by the University of California Santa Barbara Air Products Fellowship and by the National Science Foundation (EFRI-1038234). T.H. and K.D. acknowledge financial support via a Grant-in-Aids for Specially Promoted Research (no. 23000009) of the Japan Society for the Promotion of Science (JSPS). F.E.O. thanks Research Corporation for Science Advancement for a Scialog award and the National Science Foundation under CHE \u2013 1152250 and CBET 1133099. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the author and do not necessarily reflect the views of the National Science Foundation. S.A. acknowledges support from the Department of Chemistry and the School of Physical Sciences at the University of California Irvine and the U.S. Department of Energy under Award No. DE-EE0006963. A summary version of this review paper (DOI: 10.2172/1179198), and associated summary tables that will be updated as the field progresses, will be available on the working group website (http://energy.gov/eere/fuelcells/photoelectrochemical-working-group).\n\nPublished - c5ee01434d.pdf
", "abstract": "Reactors based on particle suspensions for the capture, conversion, storage, and use of solar energy as H_2 are projected to be cost-competitive with fossil fuels. In light of this, this review paper summarizes state-of-the-art particle light absorbers and cocatalysts as suspensions (photocatalysts) that demonstrate visible-light-driven water splitting on the laboratory scale. Also presented are reactor descriptions, theoretical considerations particular to particle suspension reactors, and efficiency and performance characterization metrics. Opportunities for targeted research, analysis, and development of reactor designs are highlighted.", "date": "2015-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2825-2850", "id_number": "CaltechAUTHORS:20151030-125812115", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151030-125812115", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DGE-1321846" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of California, Santa Barbara" }, { "agency": "NSF", "grant_number": "EFRI-1038234" }, { "agency": "Japan Society for the Promotion of Science (JSPS)", "grant_number": "23000009" }, { "agency": "NSF", "grant_number": "CHE\u20131152250" }, { "agency": "NSF", "grant_number": "CBET-1133099" }, { "agency": "University of California, Irvine" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-EE0006963" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C5EE01434D", "primary_object": { "basename": "c5ee01434d.pdf", "url": "https://authors.library.caltech.edu/records/64cr5-dje08/files/c5ee01434d.pdf" }, "pub_year": "2015", "author_list": "Fabian, David M.; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/s4vym-kha78", "eprint_id": 59341, "eprint_status": "archive", "datestamp": "2023-08-22 16:20:57", "lastmod": "2023-10-23 20:28:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suseno-Sandy", "name": { "family": "Suseno", "given": "Sandy" } }, { "id": "McCrory-Charles-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Tran-Rosalie", "name": { "family": "Tran", "given": "Rosalie" } }, { "id": "Gul-Sheraz", "name": { "family": "Gul", "given": "Sheraz" }, "orcid": "0000-0001-8920-8737" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Agapie-T", "name": { "family": "Agapie", "given": "Theodor" }, "orcid": "0000-0002-9692-7614" } ] }, "title": "Molecular Mixed-Metal Manganese Oxido Cubanes as Precursors to Heterogeneous Oxygen Evolution Catalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "cubanes; electrocatalysis; manganese; metal oxides; oxygen evolution reaction", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: March 20, 2015. Article first published online: 4 Aug. 2015.\n\nThis work was supported by Caltech, the NSF CAREER grant CHE-1151918 and the NIH grant R01 GM102687A (T.A.). T.A. is a Sloan, Cottrell, and Dreyfus fellow. Rotating-disk voltammetry and 2 h stability measurements are based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award no. DESC0004993. Portions of this research were carried out at the SSRL, operated by Stanford University for the U.S. DOE Office of Science, and supported by the DOE and NIH. X-ray spectroscopy studies were supported by the NIH (R.T.) and by the Director of the OBES, Division of Chemical Sciences, Geosciences, and Biosciences, DOE (J.Y.). We thank James D. Blakemore for helpful discussions, Nathan Dalleska for assistance in ICP-MS data acquisition, and Tim Davenport for assistance in TGA studies. We thank Dr. Jordi Cabana and Dr. Ulrike Boesenberg for providing the NiO reference spectrum. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. This project benefited from the use of instrumentation made available by the Caltech Environmental Analysis Center.\n\nAccepted Version - nihms785201.pdf
Supplemental Material - chem_201501104_sm_miscellaneous_information.pdf
", "abstract": "Well-defined mixed-metal [CoMn\u2083O\u2084] and [NiMn\u2083O\u2084] cubane complexes were synthesized and used as precursors for heterogeneous oxygen evolution reaction (OER) electrocatalysts. The discrete clusters were dropcasted onto glassy carbon (GC) and indium tin oxide (ITO) electrodes, and the OER activities of the resulting films were evaluated. The catalytic surfaces were analyzed by various techniques to gain insight into the structure-function relationships of the electrocatalysts' heterometallic composition. Depending on preparation conditions, the Co-Mn oxide was found to change metal composition during catalysis, while the Ni\u2013Mn oxides maintained the NiMn\u2083 ratio. XAS studies provided structural insights indicating that the electrocatalysts are different from the molecular precursors, but that the original NiMn\u2083O\u2084 cubane-like geometry was maintained in the absence of thermal treatment (2-Ni). In contrast, the thermally generated 3-Ni develops an oxide-like extended structure. Both 2-Ni and 3-Ni undergo structural changes upon electrolysis, but they do not convert into the same material. The observed structural motifs in these heterogeneous electrocatalysts are reminiscent of the biological oxygen-evolving complex in Photosystem II, including the MMn\u2083O\u2084 cubane moiety. The reported studies demonstrate the use of discrete heterometallic oxide clusters as precursors for heterogeneous water oxidation catalysts of novel composition and the distinct behavior of two sets of mixed metal oxides.", "date": "2015-09-14", "date_type": "published", "publication": "Chemistry: a European Journal", "volume": "21", "number": "38", "publisher": "John Wiley & Sons", "pagerange": "13420-13430", "id_number": "CaltechAUTHORS:20150810-085304566", "issn": "0947-6539", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150810-085304566", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Caltech" }, { "agency": "NSF", "grant_number": "CHE-1151918" }, { "agency": "NIH", "grant_number": "R01 GM102687A" }, { "agency": "Alfred P. Sloan Foundation" }, { "agency": "Cottrell Scholar of Research Corporation" }, { "agency": "Camille and Henry Dreyfus Foundation" }, { "agency": "Department of Energy (DOE)", "grant_number": "SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/chem.201501104", "pmcid": "PMC4868073", "primary_object": { "basename": "chem_201501104_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/s4vym-kha78/files/chem_201501104_sm_miscellaneous_information.pdf" }, "related_objects": [ { "basename": "nihms785201.pdf", "url": "https://authors.library.caltech.edu/records/s4vym-kha78/files/nihms785201.pdf" } ], "pub_year": "2015", "author_list": "Suseno, Sandy; McCrory, Charles C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/66hw7-jws13", "eprint_id": 59172, "eprint_status": "archive", "datestamp": "2023-08-20 08:04:50", "lastmod": "2023-10-23 20:08:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Friedrich-Dennis", "name": { "family": "Friedrich", "given": "Dennis" }, "orcid": "0000-0003-4844-368X" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Yang-Fan", "name": { "family": "Yang", "given": "Fan" } }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Nielander-Adam-C", "name": { "family": "Nielander", "given": "Adam C." }, "orcid": "0000-0002-3639-2427" }, { "id": "Yalamanchili-Sisir", "name": { "family": "Yalamanchili", "given": "Sisir" } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Interface engineering of the photoelectrochemical performance of Ni-oxide-coated n-Si photoanodes by atomic-layer deposition of ultrathin films of cobalt oxide", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry.\n\nReceived 30th May 2015, Accepted 15th July 2015, First published online 15 Jul 2015. \n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. UV-VIS spectroscopy, atomic-force microscopy, and Kelvin probe force microscopy were performed at the Molecular Materials Resource Center (MMRC) of the Beckman Institute at the California Institute of Technology. ACN was supported by a Graduate Research Fellowship from the National Science Foundation. This work was additionally supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. \n\nAuthor contribution: X.Z., R.L., K.S., K.M.P, B.S.B and N.S.L designed the experiments and wrote the manuscript. X.Z., R.L., K.S., D.F., M.T.M, F.Y., S.T.O., F.H.S., A.C.N., S.Y. performed the experiments.\n\nPublished - Zhou_2015p2644.pdf
Supplemental Material - c5ee01687h1_si.pdf
", "abstract": "Introduction of an ultrathin (2 nm) film of cobalt oxide (CoO_x) onto n-Si photoanodes prior to sputter-deposition of a thick multifunctional NiO_x coating yields stable photoelectrodes with photocurrent-onset potentials of ~\u2212240 mV relative to the equilibrium potential for O2(g) evolution and current densities of ~28 mA cm^(\u22122) at the equilibrium potential for water oxidation when in contact with 1.0 M KOH(aq) under 1 sun of simulated solar illumination. The photoelectrochemical performance of these electrodes was very close to the Shockley diode limit for moderately doped n-Si(100) photoelectrodes, and was comparable to that of typical protected Si photoanodes that contained np+ buried homojunctions.", "date": "2015-09-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "2644-2649", "id_number": "CaltechAUTHORS:20150804-104946656", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150804-104946656", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ee01687h", "primary_object": { "basename": "Zhou_2015p2644.pdf", "url": "https://authors.library.caltech.edu/records/66hw7-jws13/files/Zhou_2015p2644.pdf" }, "related_objects": [ { "basename": "c5ee01687h1_si.pdf", "url": "https://authors.library.caltech.edu/records/66hw7-jws13/files/c5ee01687h1_si.pdf" } ], "pub_year": "2015", "author_list": "Zhou, Xinghao; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/0w1et-cwv76", "eprint_id": 60354, "eprint_status": "archive", "datestamp": "2023-08-20 08:05:17", "lastmod": "2023-10-24 16:28:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Singh-M-R", "name": { "family": "Singh", "given": "Meenesh R." }, "orcid": "0000-0002-3638-8866" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "An electrochemical engineering assessment of the operational conditions and constraints for solar-driven water-splitting systems at near-neutral pH", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry.\n\nReceived 3rd June 2015, Accepted 29th June 2015, First published online 30 Jun 2015.\n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award number DE-SC0004993.\n\nPublished - Singh_2015p2760.pdf
Supplemental Material - c5ee01721a1_si.pdf
", "abstract": "The solution transport losses in a one-dimensional solar-driven water-splitting cell that operates in either concentrated acid, dilute acid, or buffered near-neutral pH electrolytes have been evaluated using a mathematical model that accounts for diffusion, migration and convective transport, as well as for bulk electrochemical reactions in the electrolyte. The Ohmic resistance loss, the Nernstian potential loss associated with pH gradients at the surface of the electrode, and electrodialysis in different electrolytes were assessed quantitatively in a stagnant cell as well as in a bubble-convected cell, in which convective mixing occurred due to product-gas evolution. In a stagnant cell that did not have convective mixing, small limiting current densities (<3 mA cm^(\u22122)) and significant polarization losses derived from pH gradients were present in dilute acid as well as in near-neutral pH buffered electrolytes. In contrast, bubble-convected cells exhibited a significant increase in the limiting current density, and a significant reduction of the concentration overpotentials. In a bubble-convected cell, minimal solution transport losses were present in membrane-free cells, in either buffered electrolytes or in unbuffered solutions with pH \u2264 1. However, membrane-free cells lack a mechanism for product-gas separation, presenting significant practical and engineering impediments to the deployment of such systems. To produce an intrinsically safe cell, an ion-exchange membrane was incorporated into the cell. The accompanying solution losses, especially the pH gradients at the electrode surfaces, were modeled and simulated for such a system. Hence this work describes the general conditions under which intrinsically safe, efficient solar-driven water-splitting cells can be operated.", "date": "2015-09-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "9", "publisher": "Royal Society of Chemistry", "pagerange": "2760-2767", "id_number": "CaltechAUTHORS:20150918-153945062", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150918-153945062", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ee01721a", "primary_object": { "basename": "Singh_2015p2760.pdf", "url": "https://authors.library.caltech.edu/records/0w1et-cwv76/files/Singh_2015p2760.pdf" }, "related_objects": [ { "basename": "c5ee01721a1_si.pdf", "url": "https://authors.library.caltech.edu/records/0w1et-cwv76/files/c5ee01721a1_si.pdf" } ], "pub_year": "2015", "author_list": "Singh, Meenesh R.; Papadantonakis, Kimberly M.; et el." }, { "id": "https://authors.library.caltech.edu/records/gp88m-1th21", "eprint_id": 61885, "eprint_status": "archive", "datestamp": "2023-08-20 08:00:58", "lastmod": "2023-10-25 16:02:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "May-Matthias-M", "name": { "family": "May", "given": "Matthias M." }, "orcid": "0000-0002-1252-806X" }, { "id": "Lewerenz-Hans-Joachim", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Lackner-David", "name": { "family": "Lackner", "given": "David" }, "orcid": "0000-0001-8170-0874" }, { "id": "Dimroth-Frank", "name": { "family": "Dimroth", "given": "Frank" }, "orcid": "0000-0002-3615-4437" }, { "id": "Hannappel-Thomas", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" } ] }, "title": "Efficient direct solar-to-hydrogen conversion by in situ interface transformation of a tandem structure", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. \n\nReceived 4 Feb 2015; Accepted 7 Aug 2015; Published 15 Sep 2015. \n\nWe are grateful for support by R. van de Krol and for experimental support by M. Kernbach and H. Kriegel. M. Niemeyer, C. Karcher and J. Ohlmann supported the solar cell development. K. Harbauer and T. M\u00fcnchenberg assisted with ohmic contact preparation. U. Bloeck performed the TEM measurements, S. Brunken provided the RuO2 counter electrode. We also thank P. Bogdanoff, K. Fountaine and C. McCrory for helpful discussions. M.M.M. acknowledges a scholarship by the Studienstiftung des deutschen Volkes and H.-J.L. acknowledges support by the DFG (project Nr. 1192-3/4). The discussion and interpretation of the data, feedback with experimentation as well as article layout and writing was also supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. \n\nContributions: T.H., H.-J.L. and M.M.M. designed the study. M.M.M. executed the experiments and did the data analysis. D.L. and F.D. prepared the tandem absorber. M.M.M. and H.J.L. wrote the paper and all authors commented on the manuscript. \n\nThe authors declare no competing financial interests.\n\nPublished - ncomms9286.pdf
Supplemental Material - ncomms9286-s1.pdf
", "abstract": "Photosynthesis is nature's route to convert intermittent solar irradiation into storable energy, while its use for an industrial energy supply is impaired by low efficiency. Artificial photosynthesis provides a promising alternative for efficient robust carbon-neutral renewable energy generation. The approach of direct hydrogen generation by photoelectrochemical water splitting utilizes customized tandem absorber structures to mimic the Z-scheme of natural photosynthesis. Here a combined chemical surface transformation of a tandem structure and catalyst deposition at ambient temperature yields photocurrents approaching the theoretical limit of the absorber and results in a solar-to-hydrogen efficiency of 14%. The potentiostatically assisted photoelectrode efficiency is 17%. Present benchmarks for integrated systems are clearly exceeded. Details of the in situ interface transformation, the electronic improvement and chemical passivation are presented. The surface functionalization procedure is widely applicable and can be precisely controlled, allowing further developments of high-efficiency robust hydrogen generators.", "date": "2015-09", "date_type": "published", "publication": "Nature Communications", "volume": "6", "number": "9", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 8286", "id_number": "CaltechAUTHORS:20151105-084800992", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151105-084800992", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Studienstiftung des deutschen Volkes" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "1192-3/4" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/ncomms9286", "pmcid": "PMC4579846", "primary_object": { "basename": "ncomms9286-s1.pdf", "url": "https://authors.library.caltech.edu/records/gp88m-1th21/files/ncomms9286-s1.pdf" }, "related_objects": [ { "basename": "ncomms9286.pdf", "url": "https://authors.library.caltech.edu/records/gp88m-1th21/files/ncomms9286.pdf" } ], "pub_year": "2015", "author_list": "May, Matthias M.; Lewerenz, Hans-Joachim; et el." }, { "id": "https://authors.library.caltech.edu/records/mjegz-jvf34", "eprint_id": 59887, "eprint_status": "archive", "datestamp": "2023-08-20 07:54:03", "lastmod": "2023-10-23 22:48:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Plymale-Noah-T", "name": { "family": "Plymale", "given": "Noah T." }, "orcid": "0000-0003-2564-8009" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Synthesis, Characterization, and Reactivity of Ethynyl- and Propynyl-Terminated Si(111) Surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: May 26, 2015, Revised: July 7, 2015, Publication Date (Web): July 10, 2015. \n\nWe acknowledge the National Science Foundation Grant No. CHE-1214152 and the Molecular Materials Research Center of the Beckman Institute at the California Institute of Technology for support. N.T.P. acknowledges support from the NSF for a Graduate Research Fellowship. Support for Y.-G.K. and M.P.S. to perform the EC-STM experiments was provided by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We thank Dr. Leslie E. O'Leary, Dr. Ronald L. Grimm, and Mr. Christopher W. Roske for helpful discussions. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - jp5b05028_si_001.pdf
", "abstract": "Ethynyl- and propynyl-terminated Si(111) surfaces synthesized using a two-step halogenation/alkylation method have been characterized by transmission infrared spectroscopy (TIRS), high-resolution electron energy-loss spectroscopy (HREELS), X-ray photoelectron spectroscopy (XPS), low-energy electron diffraction (LEED), atomic-force microscopy (AFM), electrochemical scanning\u2013tunneling microscopy (EC-STM) and measurements of surface recombination velocities (S). For the ethynyl-terminated Si(111) surface, TIRS revealed signals corresponding to ethynyl \u2261C\u2013H and C\u2261C stretching oriented perpendicular to the surface, HREELS revealed a Si\u2013C stretching signal, and XPS data showed the presence of C bound to Si with a fractional monolayer (ML) coverage (\u03a6) of \u03a6_(Si\u2013CCH) = 0.63 \u00b1 0.08 ML. The ethynyl-terminated surfaces were also partially terminated by Si\u2013OH groups (\u03a6_(Si\u2013OH) = 0.35 \u00b1 0.03 ML) with limited formation of Si^(3+) and Si^(4+) oxides. For the propynyl-terminated Si(111) surface, TIRS revealed the presence of a (C\u2013H)CH_3 symmetric bending, or \"umbrella,\" peak oriented perpendicular to the surface, while HREELS revealed signals corresponding to Si\u2013C and C\u2261C stretching, and XPS showed C bound to Si with \u03a6_(Si\u2013CCCH_3) = 1.05 \u00b1 0.06 ML. The LEED patterns were consistent with a (1 \u00d7 1) surface unit cell for both surfaces, but room-temperature EC-STM indicated that the surfaces did not exhibit long-range ordering. HCC\u2013Si(111) and CH_3CC\u2013Si(111) surfaces yielded S values of (3.5 \u00b1 0.1) \u00d7 10^3 and (5 \u00b1 1) \u00d7 10^2 cm s^(\u20131), respectively, after 581 h exposure to air. These observations are consistent with the covalent binding of ethynyl and propynyl groups, respectively, to the Si(111) surface.", "date": "2015-08-27", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "119", "number": "34", "publisher": "American Chemical Society", "pagerange": "19847-19862", "id_number": "CaltechAUTHORS:20150825-113614153", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150825-113614153", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Caltech Beckman Institute" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/acs.jpcc.5b05028", "primary_object": { "basename": "jp5b05028_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mjegz-jvf34/files/jp5b05028_si_001.pdf" }, "pub_year": "2015", "author_list": "Plymale, Noah T.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/f2x75-4wx06", "eprint_id": 58774, "eprint_status": "archive", "datestamp": "2023-08-20 07:40:44", "lastmod": "2023-10-23 19:42:24", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias H." }, "orcid": "0000-0003-0091-2045" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Axnanda-S", "name": { "family": "Axnanda", "given": "Stephanus" } }, { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter" }, "orcid": "0000-0002-8693-4562" }, { "id": "Hussain-Z", "name": { "family": "Hussain", "given": "Zahid" } }, { "id": "Mayer-T", "name": { "family": "Mayer", "given": "Thomas" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Liu-Zhi", "name": { "family": "Liu", "given": "Zhi" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Direct observation of the energetics at a semiconductor/liquid junction by operando X-ray photoelectron spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Royal Society of Chemistry. \n\nReceived 30th March 2015; accepted 29th May 2015. First published online 29 May 2015. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract no. DE-AC02-05CH11231. We acknowledge Dr. Philip Ross for his contributions to the conceptual development of the AP-XPS endstation and experimental design, and Junko Yano for fruitful discussions. We acknowledge Fadl Saadi, Beomgyun Jeong, and Sana Rani for assistance during data collection at the beamline.\n\nPublished - c5ee01014d.pdf
Supplemental Material - c5ee01014d1.pdf
", "abstract": "Photoelectrochemical (PEC) cells based on semiconductor/liquid interfaces provide a method of converting solar energy to electricity or fuels. Currently, the understanding of semiconductor/liquid interfaces is inferred from experiments and models. Operando ambient-pressure X-ray photoelectron spectroscopy (AP-XPS) has been used herein to directly characterize the semiconductor/liquid junction at room temperature under real-time electrochemical control. X-ray synchrotron radiation in conjunction with AP-XPS has enabled simultaneous monitoring of the solid surface, the solid/electrolyte interface, and the bulk electrolyte of a PEC cell as a function of the applied potential, U. The observed shifts in binding energy with respect to the applied potential have directly revealed ohmic and rectifying junction behavior on metallized and semiconducting samples, respectively. Additionally, the non-linear response of the core level binding energies to changes in the applied electrode potential has revealed the influence of defect-derived electronic states on the Galvani potential across the complete cell.", "date": "2015-08-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "8", "publisher": "Royal Society of Chemistry", "pagerange": "2409-2416", "id_number": "CaltechAUTHORS:20150706-104957791", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150706-104957791", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C5EE01014D", "primary_object": { "basename": "c5ee01014d.pdf", "url": "https://authors.library.caltech.edu/records/f2x75-4wx06/files/c5ee01014d.pdf" }, "related_objects": [ { "basename": "c5ee01014d1.pdf", "url": "https://authors.library.caltech.edu/records/f2x75-4wx06/files/c5ee01014d1.pdf" } ], "pub_year": "2015", "author_list": "Lichterman, Michael F.; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/n964t-6zc97", "eprint_id": 58885, "eprint_status": "archive", "datestamp": "2023-08-20 07:22:28", "lastmod": "2023-10-23 19:50:37", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Wong-Keith-T", "name": { "family": "Wong", "given": "Keith T." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Synthesis and Characterization of Atomically Flat Methyl-Terminated Ge(111) Surfaces", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: March 31, 2015; publication Date (Web): July 8, 2015. \n\nThis work was supported by the National Science Foundation grant CHE-1214152 and by the Gordon and Betty Moore Foundation (GBMF1225). The research was in part carried out in the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology and in part through the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993, which provided support for Y.-G.K. and M.P.S. to perform the EC-STM experiments. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja5b03339_si_001.pdf
", "abstract": "Atomically flat, terraced H\u2013Ge(111) was prepared by annealing in H_2(g) at 850 \u00b0C. The formation of monohydride Ge\u2013H bonds oriented normal to the surface was indicated by angle-dependent Fourier-transform infrared (FTIR) spectroscopy. Subsequent reaction in CCl_3Br(l) formed Br-terminated Ge(111), as shown by the disappearance of the Ge\u2013H absorption in the FTIR spectra concomitant with the appearance of Br photoelectron peaks in X-ray photoelectron (XP) spectra. The Br\u2013Ge(111) surface was methylated by reaction with (CH_3)_2Mg. These surfaces exhibited a peak at 568 cm^\u20131 in the high-resolution electron energy loss spectrum, consistent with the formation of a Ge\u2013C bond. The absorption peaks in the FTIR spectra assigned to methyl \"umbrella\" and rocking modes were dependent on the angle of the incident light, indicating that the methyl groups were bonded directly atop surface Ge atoms. Atomic-force micrographs of CH_3\u2013Ge(111) surfaces indicated that the surface remained atomically flat after methylation. Electrochemical scanning\u2013tunneling microscopy showed well-ordered methyl groups that covered nearly all of the surface. Low-energy electron diffraction images showed sharp, bright diffraction spots with a 3-fold symmetry, indicating a high degree of order with no evidence of surface reconstruction. A C 1s peak at 284.1 eV was observed in the XP spectra, consistent with the formation of a C\u2013Ge bond. Annealing in ultrahigh vacuum revealed a thermal stability limit of \u223c400 \u00b0C of the surficial CH_3\u2013Ge(111) groups. CH_3\u2013Ge(111) surfaces showed significantly greater resistance to oxidation in air than H\u2013Ge(111) surfaces.", "date": "2015-07-22", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "137", "number": "28", "publisher": "American Chemical Society", "pagerange": "9006-9014", "id_number": "CaltechAUTHORS:20150714-134139272", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150714-134139272", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.5b03339", "primary_object": { "basename": "ja5b03339_si_001.pdf", "url": "https://authors.library.caltech.edu/records/n964t-6zc97/files/ja5b03339_si_001.pdf" }, "pub_year": "2015", "author_list": "Wong, Keith T.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/hzr78-4ft45", "eprint_id": 58896, "eprint_status": "archive", "datestamp": "2023-08-20 07:22:38", "lastmod": "2023-10-23 19:51:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "The Influence of Structure and Processing on the Behavior of TiO_2 Protective Layers for Stabilization of n-Si/TiO_2/Ni Photoanodes for Water Oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: January 13, 2015, Accepted: June 17, 2015, Publication Date (Web): June 17, 2015. \n\nThis material is based upon work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. TEM data were collected at the Caltech Transmission Electron Microscopy Facility. A.I.C. recognizes a Graduate Research Fellowship from the National Science Foundation for support. The authors gratefully acknowledge the assistance of Dr. Yunbin Guan during collection of SIMS data. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - am5b00379_si_001.pdf
", "abstract": "Light absorbers with moderate band gaps (1\u20132 eV) are required for high-efficiency solar fuels devices, but most semiconducting photoanodes undergo photocorrosion or passivation in aqueous solution. Amorphous TiO_2 deposited by atomic-layer deposition (ALD) onto various n-type semiconductors (Si, GaAs, GaP, and CdTe) and coated with thin films or islands of Ni produces efficient, stable photoanodes for water oxidation, with the TiO_2 films protecting the underlying semiconductor from photocorrosion in pH = 14 KOH(aq). The links between the electronic properties of the TiO_2 in these electrodes and the structure and energetic defect states of the material are not yet well-elucidated. We show herein that TiO_2 films with a variety of crystal structures and midgap defect state distributions, deposited using both ALD and sputtering, form rectifying junctions with n-Si and are highly conductive toward photogenerated carriers in n-Si/TiO_2/Ni photoanodes. Moreover, the photovoltage of these electrodes can be modified by annealing the TiO_2 in reducing or oxidizing environments. All of the polycrystalline TiO_2 films with compact grain boundaries investigated herein protected the n-Si photoanodes against photocorrosion in pH = 14 KOH(aq). Hence, in these devices, conduction through the TiO_2 layer is neither specific to a particular amorphous or crystalline structure nor determined wholly by a particular extrinsic dopant impurity. The coupled structural and energetic properties of TiO_2, and potentially other protective oxides, can therefore be controlled to yield optimized photoelectrode performance.", "date": "2015-07-22", "date_type": "published", "publication": "ACS Applied Materials & Interfaces", "volume": "7", "number": "28", "publisher": "American Chemical Society", "pagerange": "15189-15199", "id_number": "CaltechAUTHORS:20150715-142850363", "issn": "1944-8244", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150715-142850363", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acsami.5b00379", "primary_object": { "basename": "am5b00379_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hzr78-4ft45/files/am5b00379_si_001.pdf" }, "pub_year": "2015", "author_list": "McDowell, Matthew T.; Lichterman, Michael F.; et el." }, { "id": "https://authors.library.caltech.edu/records/3n6th-06065", "eprint_id": 68223, "eprint_status": "archive", "datestamp": "2023-08-20 07:16:07", "lastmod": "2023-10-19 22:10:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Nocera-Daniel-G", "name": { "family": "Nocera", "given": "Daniel G." }, "orcid": "0000-0001-5055-320X" } ] }, "title": "The solar opportunity", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 by the National Academy of Sciences. \n\nNSL acknowledges support from the National Science Foundation (CHE-1214152), the Department of Energy Office of Science through the Joint Center for Artificial Photosynthesis (grant DE-SC0004993), and the DOE Office of Science (grant DE-FG02-03ER15483). DGN acknowledges support from the US DOE Office of Science (grant DE-SC0009565), Air Force Office of Scientific Research (grant FA9550-09-1-0689), and the TomKat Trust.", "abstract": "Solar energy utilization poses a vexing conundrum: at present, we cannot afford to use it, but eventually we probably cannot afford not to use it. The promise rests in the unmatched size of the solar resource: more energy from the sun strikes the Earth in one hour than all of the energy consumed on the planet in an entire year (DOE 2005; Lewis and Nocera 2006). \n\nAs with all energy sources, challenges for solar energy use reside in the \"cost of extraction.\" The diffuseness of solar energy, typically providing a yearly averaged power density of about 200 W/m2 at representative midlatitudes, requires the coverage of relatively large areas with a sunlight capture system, in turn requiring very inexpensive but high-performance materials and balance of systems to be viable. Additionally, to contribute to a large fraction of a global energy system, use of solar energy requires concomitant development of an accompanying technological approach to provide tera-watt (TW)-days of reliable, robust, persistent, scalable, and cost-effective energy storage.", "date": "2015-07-03", "date_type": "published", "publication": "The Bridge", "volume": "45", "number": "2", "publisher": "National Academy of Engineering", "pagerange": "41-47", "id_number": "CaltechAUTHORS:20160616-173850450", "issn": "0737-6278", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20160616-173850450", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0009565" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-09-1-0689" }, { "agency": "TomKat Charitable Trust" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "pub_year": "2015", "author_list": "Lewis, Nathan S. and Nocera, Daniel G." }, { "id": "https://authors.library.caltech.edu/records/rcy10-7av17", "eprint_id": 57205, "eprint_status": "archive", "datestamp": "2023-08-22 15:52:23", "lastmod": "2023-10-23 17:09:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Ferrer-I-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Smets-A-H-M", "name": { "family": "Smets", "given": "Arno H. M." } }, { "id": "Zeman-M", "name": { "family": "Zeman", "given": "Miro" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A low-temperature synthesis of electrochemical active Pt nanoparticles and thin films by atomic layer deposition on Si(111) and glassy carbon surfaces", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Atomic layer deposition; Platinum; Nanoparticles; Thin films; Water splitting; Hydrogen evolution", "note": "\u00a9 2015 Elsevier B.V.\n\nReceived 29 August 2014; Received in revised form 6 April 2015; Accepted 9 April 2015; Available online 18 April 2015.\n\nThis work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. BSB was supported by the Beckmann Institute of California Institute of Technology. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. LH would like to thank the VIDI project granted to Dr. Arno H.M. Smets by NWO-STW to financially support his stay in California Institute of Technology.", "abstract": "Atomic layer deposition (ALD) was used to deposit nanoparticles and thin films of Pt onto etched p-type Si(111) wafers and glassy carbon discs. Using precursors of MeCpPtMe_3 and ozone and a temperature window of 200\u2013300 \u00b0C, the growth rate was 80\u2013110 pm/cycle. X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) were used to analyze the composition, structure, morphology, and thickness of the ALD-grown Pt nanoparticle films. The catalytic activity of the ALD-grown Pt for the hydrogen evolution reaction was shown to be equivalent to that of e-beam evaporated Pt on glassy carbon electrode.", "date": "2015-07-01", "date_type": "published", "publication": "Thin Solid Films", "volume": "586", "publisher": "Elsevier", "pagerange": "28-34", "id_number": "CaltechAUTHORS:20150504-140234191", "issn": "0040-6090", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150504-140234191", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.tsf.2015.04.018", "pub_year": "2015", "author_list": "Liu, Rui; Han, Lihao; et el." }, { "id": "https://authors.library.caltech.edu/records/nbzks-p3g03", "eprint_id": 62602, "eprint_status": "archive", "datestamp": "2023-08-22 15:51:14", "lastmod": "2023-10-25 17:16:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kuang-Yanjin", "name": { "family": "Kuang", "given": "Yanjin" }, "orcid": "0000-0002-2191-6654" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Sukrittanon-S", "name": { "family": "Sukrittanon", "given": "Supanee" } }, { "id": "Takabayashi-Ko", "name": { "family": "Takabayashi", "given": "Ko" } }, { "id": "Kamiya-Itaru", "name": { "family": "Kamiya", "given": "Itaru" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Tu-Charles-W", "name": { "family": "Tu", "given": "Charles W." } } ] }, "title": "Enhancement of the performance of GaP solar cells by embedded In(N)P quantum dots", "ispublished": "pub", "full_text_status": "public", "keywords": "Quantum dots; InNP; Solar cells; Indirect bandgap engineering; MBE", "note": "\u00a9 2015 Elsevier. \n\nReceived 3 February 2015, Revised 18 May 2015, Accepted 8 June 2015, Available online 17 June 2015.", "abstract": "Improving the utilization of solar spectra of wide bandgap semiconductors that can potentially provide enough free energy is one of the promising strategies for realizing efficient and spontaneous integrated conversion of solar energy to chemical fuels. We demonstrate herein that nitrogen doped InP quantum dots (QDs) embedded in wide bandgap GaP could improve the solar energy conversion performance. Photoelectrochemical experiments in contact with a nonaqueous, reversible redox couple indicated that the QD-embedded devices exhibited improved performance relative to devices without QDs, with short-circuit current densities increasing from 0.16 mA cm^(\u22122) for GaP-only devices to 0.23 and 0.29 mA cm^(\u22122) for InP and InNP QD-embedded devices, respectively. Additionally, the open-circuit voltages increased from 0.95 V for GaP-only devices to 1.11 and 1.14 V for InP and InNP QD-embedded devices, respectively, and the external quantum yield of the devices was also enhanced by the embedded QDs. The improvement is attributed to the absorption of sub-bandgap photons by the In(N)P QDs.", "date": "2015-07", "date_type": "published", "publication": "Nano Energy", "volume": "15", "publisher": "Elsevier", "pagerange": "782-788", "id_number": "CaltechAUTHORS:20151204-091530978", "issn": "2211-2855", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151204-091530978", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1016/j.nanoen.2015.06.003", "pub_year": "2015", "author_list": "Kuang, Yanjin; Sun, Ke; et el." }, { "id": "https://authors.library.caltech.edu/records/gnvs8-3yh27", "eprint_id": 62754, "eprint_status": "archive", "datestamp": "2023-08-20 07:08:37", "lastmod": "2023-10-25 17:22:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Stephani-C", "name": { "family": "Stephani", "given": "Carolynn" } }, { "id": "Tan-Kian-L", "name": { "family": "Tan", "given": "Kian L." } }, { "id": "Wang-Dunwei", "name": { "family": "Wang", "given": "Dunwei" } } ] }, "title": "Tuning redox potentials of CO_2 reduction catalysts for carbon photofixation by Si nanowires", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Science China Press and Springer-Verlag Berlin Heidelberg. \n\nPublished online 15 July 2015. \n\nThe project was supported in part by US National Science Foundation (DMR 1055762) to Wang D and US National Institute of General Medical Sciences (R01GM08758) to Tan KL. Liu R is partially supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. \n\nAuthor contributions: Liu R, Tan KL and Wang D designed the project\nand the experiments. Liu R and Stephani C performed the experiments. Liu R and Wang D analyzed the results and wrote the paper. \n\nThe authors declare that they have no conflict of interest.\n\nSupplemental Material - 40843_2015_68_MOESM1_ESM.pdf
", "abstract": "Si nanowires (SiNWs) are shown to absorb visible light to reduce Ni catalysts into Ni^0 compounds, enabling alkyne carboxylation reactions with CO_2 as a carbon feedstock. The reduced Ni catalysts are effective in CO_2 fixation through a 4-octyne carboxylation reaction. The reduction potentials of the Ni catalysts can be tuned from -1.35 to -0.51 V (vs. saturated calomel electrode) by altering the binding ligands. The results shed light on the nature of charge transfer from SiNWs to the catalyst for this new class of photocatalytic reactions. By controlling the CO_2 reduction potential of the catalysts with carefully ligand designs, it will bring more opportunities and options to realize the highly selective, effective and sustainable CO_2 reduction in the future.", "date": "2015-07", "date_type": "published", "publication": "Science China Materials", "volume": "58", "number": "7", "publisher": "Springer", "pagerange": "515-520", "id_number": "CaltechAUTHORS:20151209-135417487", "issn": "2095-8226", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20151209-135417487", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1055762" }, { "agency": "National Institute of General Medical Sciences", "grant_number": "R01GM08758" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s40843-015-0068-8", "primary_object": { "basename": "40843_2015_68_MOESM1_ESM.pdf", "url": "https://authors.library.caltech.edu/records/gnvs8-3yh27/files/40843_2015_68_MOESM1_ESM.pdf" }, "pub_year": "2015", "author_list": "Liu, Rui; Stephani, Carolynn; et el." }, { "id": "https://authors.library.caltech.edu/records/cy499-hvg44", "eprint_id": 58090, "eprint_status": "archive", "datestamp": "2023-08-20 06:49:07", "lastmod": "2023-10-23 19:01:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Kuang-Yanjin", "name": { "family": "Kuang", "given": "Yanjin" }, "orcid": "0000-0002-2191-6654" }, { "id": "Verlage-E", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Tu-Charles-W", "name": { "family": "Tu", "given": "Charles W." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Sputtered NiO_x Films for Stabilization of p^+n-lnP Photoanodes for Solar-Driven Water Oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Wiley\u00b7VCH Verlag GmbH & Co. \n\nArticle first Received: December 17, 2014. Revised : February 6, 2015. Published online: March 18, 2015. \n\nThis work was supported th rough the Office of Science of the U.S. Department of Energy (DOE) under Award No. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. Material growth by GSMBE was supported by the National Science Foundation (NSF) under Grant Nos. DMR-0907652 and DMR-1106369. UV-vis spectroscopy was performed at the Molecular Materials Research Center (MMRC) in the Beckman Institute at the California Institute of Technology. This work was also supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. N.S.L., as well as the work at near-neutral pH, was supported by the Air Force Office of Scientific Research (AFOSR) through the Multidisciplinary University Research Initiative (MURI) under AFOSR Award No. FA9550-10-1-0572. The authors thank M. Lichterman, I. Moreno-Hernandez, and S. Hu for stimulating discussions and K. Papadantonakis for editing this paper. The authors declare no competing financial interests.\n\nSupplemental Material - aenm201402276-sup-0001-S1.pdf
", "abstract": "A photoanode protection strategy using a multifunctional NiO_x coating is presented. The ransparency/antireflectivity, low electrochromism, conduction of holes, corrosion protection, and active electrocatalysis for water-oxidation half-reaction are described.", "date": "2015-06-03", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "5", "number": "11", "publisher": "Wiley", "pagerange": "Art. No. 1402276", "id_number": "CaltechAUTHORS:20150608-142332412", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150608-142332412", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-0907652" }, { "agency": "NSF", "grant_number": "DMR-1106369" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-10-1-0572" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201402276", "primary_object": { "basename": "aenm201402276-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/cy499-hvg44/files/aenm201402276-sup-0001-S1.pdf" }, "pub_year": "2015", "author_list": "Sun, Ke; Kuang, Yanjin; et el." }, { "id": "https://authors.library.caltech.edu/records/szr4s-a9z94", "eprint_id": 57184, "eprint_status": "archive", "datestamp": "2023-09-22 22:28:51", "lastmod": "2023-10-23 23:23:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sieh-Daniel", "name": { "family": "Sieh", "given": "Daniel" } }, { "id": "Lacy-David-C", "name": { "family": "Lacy", "given": "David C." } }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Kubiak-Clifford-P", "name": { "family": "Kubiak", "given": "Clifford P." }, "orcid": "0000-0003-2186-488X" } ] }, "title": "Reduction of CO\u2082 by Pyridine Monoimine Molybdenum Carbonyl Complexes: Cooperative Metal\u2013Ligand Binding of CO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: February 4, 2015. Article first published online: 29 Apr. 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. D.C.L. is supported by the National Institutes of Health (Award Number F32M106726). The authors thank Michael Takase and Lawrence M. Henling for help with the absorption correction of the X-ray data and David VanderVelde for helpful discussions concerning NMR spectroscopy. Jesse D. Froehlich, Charles W. Machan, and Matthew D. Sampson are thanked for the introduction to IR-SEC techniques.\n\nAccepted Version - nihms711222.pdf
Supplemental Material - chem_201500463_sm_miscellaneous_information.pdf
", "abstract": "[(^(Ar)PMI)Mo(CO)\u2084] complexes (PMI=pyridine monoimine; Ar=Ph, 2,6-di-iso-propylphenyl) were synthesized and their electrochemical properties were probed with cyclic voltammetry and infrared spectroelectrochemistry (IR-SEC). The complexes undergo a reduction at more positive potentials than the related [(bipyridine)Mo(CO)\u2084] complex, which is ligand based according to IR-SEC and DFT data. To probe the reaction product in more detail, stoichiometric chemical reduction and subsequent treatment with CO\u2082 resulted in the formation of a new product that is assigned as a ligand-bound carboxylate, [(^(iPr\u2082Ph)PMI)Mo(CO)_3(CO\u2082)]\u00b2\u207b, by NMR spectroscopic methods. The CO\u2082 adduct [(^(iPr\u2082Ph)PMI)Mo(CO)_3(CO\u2082)]\u00b2\u207b could not be isolated and fully characterized. However, the C_C coupling between the CO\u2082 molecule and the PDI ligand was confirmed by X-ray crystallographic characterization of one of the decomposition products of [(^(iPr\u2082Ph)PMI)Mo(CO)_3(CO\u2082)])\u00b2\u207b.", "date": "2015-06-01", "date_type": "published", "publication": "Chemistry: a European Journal", "volume": "21", "number": "23", "publisher": "John Wiley & Sons", "pagerange": "8497-8503", "id_number": "CaltechAUTHORS:20150504-095804337", "issn": "0947-6539", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150504-095804337", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NIH", "grant_number": "F32M106726" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/chem.201500463", "pmcid": "PMC4523092", "primary_object": { "basename": "chem_201500463_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/szr4s-a9z94/files/chem_201500463_sm_miscellaneous_information.pdf" }, "related_objects": [ { "basename": "nihms711222.pdf", "url": "https://authors.library.caltech.edu/records/szr4s-a9z94/files/nihms711222.pdf" } ], "pub_year": "2015", "author_list": "Sieh, Daniel; Lacy, David C.; et el." }, { "id": "https://authors.library.caltech.edu/records/c5k1s-m1z53", "eprint_id": 57019, "eprint_status": "archive", "datestamp": "2023-09-22 22:28:56", "lastmod": "2023-10-23 23:23:04", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Audesirk-H-A", "name": { "family": "Audesirk", "given": "Heather A." } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A quantitative analysis of the efficiency of solar-driven water-splitting device designs based on tandem photoabsorbers patterned with islands of metallic electrocatalysts", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry.\n\n\nReceived 29th January 2015, Accepted 23rd March 2015, First published online 23 Mar 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. UV-VIS spectroscopy and AFM were performed at the Beckman Institute Molecular Materials Resource Center (MMRC) at the California Institute of Technology. We also thank E. Warren for stimulating discussions, Z. Huang for assistance with the AFM measurement and K. Papadantonakis for assistance on the editing of this manuscript.\n\nSupplemental Material - c5ee00311c1_si.pdf
", "abstract": "The trade-off between the optical obscuration and kinetic overpotentials of electrocatalyst films patterned onto the surface of tandem light-absorber structures in model photoelectrosynthetic water-splitting systems was investigated using a 0-dimensional load-line analysis and experimental measurements. The electrocatalytic performance of the catalyst at high current densities, normalized to the electrocatalyst surface area, is an important factor in the dependence of the optimal solar-to-hydrogen (STH) conversion efficiency, \u03b7_(STH,opt), on the filling fraction (f_c) of the patterned catalysts, because even under conditions that produce minority-carrier current densities of ~10 mA cm^(\u22122) at the solid/liquid interface, the current density at catalyst-bearing sites can be >1\u20132 A cm^(\u22122) in low filling-fraction films. A universal current-density versus potential relationship, up to current densities of 10 A cm^(\u22122), was obtained experimentally for the hydrogen-evolution reaction (HER) using patterned Pt ultramicroelectrode (UME) arrays with a range of filling fractions and disc diameters. The \u03b7_(STH,opt) of system designs that utilize patterned electrocatalysts located on the illuminated side of tandem photoabsorbers was then evaluated systematically. The maximum STH conversion efficiency, \u03b7_(STH,max), using a hypothetical electrocatalyst that was optically transparent but which nevertheless exhibited a current-density versus potential behavior that is characteristic of the most active Pt films measured experimentally regardless of their optical obscuration, was 26.7%. By comparison, the maximum \u03b7_(STH,opt) of 24.9% for real patterned Pt electrocatalyst films closely approached this ideal-case limit. The performance and materials utilization of the patterned electrocatalysts and of the uniformly coated electrocatalysts on tandem photoabsorbers were also compared in this study. Hence, patterned electrocatalysts with very low filling fractions can provide a potentially promising path to the realization of efficient large-scale photoelectrolysis systems while minimizing the use of scarce noble metals.", "date": "2015-06-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1736-1747", "id_number": "CaltechAUTHORS:20150427-134904440", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150427-134904440", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ee00311c", "primary_object": { "basename": "c5ee00311c1_si.pdf", "url": "https://authors.library.caltech.edu/records/c5k1s-m1z53/files/c5ee00311c1_si.pdf" }, "pub_year": "2015", "author_list": "Chen, Yikai; Sun, Ke; et el." }, { "id": "https://authors.library.caltech.edu/records/sxx3m-7gq05", "eprint_id": 57613, "eprint_status": "archive", "datestamp": "2023-08-20 06:23:23", "lastmod": "2023-10-23 17:34:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Yufeng", "name": { "family": "Huang", "given": "Yufeng" }, "orcid": "0000-0002-0373-2210" }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "The Reaction Mechanism with Free Energy Barriers for Electrochemical Dihydrogen Evolution on MoS_2", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: March 30, 2015. Publication Date (Web): May 5, 2015. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nPublished - jacs_2E5b03329.pdf
Supplemental Material - ja5b03329_si_001.pdf
", "abstract": "We report density functional theory (M06L) calculations including Poisson\u2013Boltzmann solvation to determine the reaction pathways and barriers for the hydrogen evolution reaction (HER) on MoS_2, using both a periodic two-dimensional slab and a Mo_(10)S_(21) cluster model. We find that the HER mechanism involves protonation of the electron rich molybdenum hydride site (Volmer\u2013Heyrovsky mechanism), leading to a calculated free energy barrier of 17.9 kcal/mol, in good agreement with the barrier of 19.9 kcal/mol estimated from the experimental turnover frequency. Hydronium protonation of the hydride on the Mo site is 21.3 kcal/mol more favorable than protonation of the hydrogen on the S site because the electrons localized on the Mo\u2013H bond are readily transferred to form dihydrogen with hydronium. We predict the Volmer\u2013Tafel mechanism in which hydrogen atoms bound to molybdenum and sulfur sites recombine to form H_2 has a barrier of 22.6 kcal/mol. Starting with hydrogen atoms on adjacent sulfur atoms, the Volmer\u2013Tafel mechanism goes instead through the M\u2013H + S\u2013H pathway. In discussions of metal chalcogenide HER catalysis, the S\u2013H bond energy has been proposed as the critical parameter. However, we find that the sulfur\u2013hydrogen species is not an important intermediate since the free energy of this species does not play a direct role in determining the effective activation barrier. Rather we suggest that the kinetic barrier should be used as a descriptor for reactivity, rather than the equilibrium thermodynamics. This is supported by the agreement between the calculated barrier and the experimental turnover frequency. These results suggest that to design a more reactive catalyst from edge exposed MoS2, one should focus on lowering the reaction barrier between the metal hydride and a proton from the hydronium in solution.", "date": "2015-05-27", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "137", "number": "20", "publisher": "American Chemical Society", "pagerange": "6692-6698", "id_number": "CaltechAUTHORS:20150518-142900035", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150518-142900035", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1121", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jacs.5b03329", "primary_object": { "basename": "ja5b03329_si_001.pdf", "url": "https://authors.library.caltech.edu/records/sxx3m-7gq05/files/ja5b03329_si_001.pdf" }, "related_objects": [ { "basename": "jacs_2E5b03329.pdf", "url": "https://authors.library.caltech.edu/records/sxx3m-7gq05/files/jacs_2E5b03329.pdf" } ], "pub_year": "2015", "author_list": "Huang, Yufeng; Nielsen, Robert J.; et el." }, { "id": "https://authors.library.caltech.edu/records/4371a-ge538", "eprint_id": 58234, "eprint_status": "archive", "datestamp": "2023-08-20 06:20:20", "lastmod": "2023-10-23 19:10:44", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Anzenburg-E", "name": { "family": "Anzenburg", "given": "Eitan" } }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Kisielowski-C", "name": { "family": "Kisielowski", "given": "Christian" }, "orcid": "0000-0001-6425-0779" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Multiphase Nanostructure of a Quinary Metal Oxide Electrocatalyst Reveals a New Direction for OER Electrocatalyst Design", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: December 23, 2014; Revised: January 23, 2015; Published online: February 27, 2015. \n\nThis work was performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC000499. Electron microscopy was performed at the Molecular Foundry which is supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. Electron transparent samples were prepared by M. Libbee at the Molecular Foundry. XAS data collection was carried out at the Stanford Synchrotron Radiation Lightsource (SSRL) beamline 7-3, operated by Stanford University for the U.S. DOE Office of Science, and supported by the DOE Office of Biological and Environmental Research, and by the NIH (including P41GM103393), and the Advanced Light Source (ALS) beamline 10.3.2, supported by DOE under Contract No. DE-AC02-05CH11231. The authors thank Dr. Ravishankar Sundararaman for insight into the equilibrium phase behavior of this system and Dr. Suho Jung for assistance with electrochemical experiments.\n\nSupplemental Material - aenm201402307-sup-0001-S1.pdf
", "abstract": "Ce-rich mixed metal oxides comprise a recently discovered class of -electrocatalysts for the oxygen evolution reaction (OER). In particular, at current densities below 10 mA cm^(\u22122), Ni_(0.3)Fe_(0.07)Co_(0.2)Ce_(0.43)O_x exhibits \u00acsuperior activity compared to the corresponding transition metal oxides, despite the relative inactivity of ceria. To elucidate the enhanced activity and underlying catalytic mechanism, detailed structural characterization of this quinary oxide electrocatalyst is reported. Transmission electron microscopy imaging of cross-section films as-prepared and after electrochemical testing reveals a stable two-phase nanostructure composed of 3\u20135 nm diameter crystallites of fluorite CeO_2 intimately mixed with 3\u20135 nm crystallites of transition metal oxides alloyed in the rock salt NiO structure. Dosing experiments demonstrate that an electron flux greater than \u22481000 e \u00c5^(\u22122) s^(\u22121) causes the inherently crystalline material to become amorphous. A very low dose rate of 130 e \u00c5^(\u22122) s^(\u22121) is employed for atomic resolution imaging using inline holography techniques to reveal a nanostructure in which the transition metal oxide nanocrystals form atomically sharp boundaries with the ceria nanocrystals, and these results are corroborated with extensive synchrotron X-ray absorption spectroscopy measurements. Ceria is a well-studied cocatalyst for other heterogeneous and electrochemical reactions, and our discovery introduces biphasic cocatalysis as a design concept for improved OER electrocatalysts.", "date": "2015-05-20", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "5", "number": "10", "publisher": "Wiley", "pagerange": "Art. No. 1402307", "id_number": "CaltechAUTHORS:20150615-085042878", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150615-085042878", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "NIH", "grant_number": "P41GM103393" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201402307", "primary_object": { "basename": "aenm201402307-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/4371a-ge538/files/aenm201402307-sup-0001-S1.pdf" }, "pub_year": "2015", "author_list": "Haber, Joel A.; Anzenburg, Eitan; et el." }, { "id": "https://authors.library.caltech.edu/records/80bzg-4hq34", "eprint_id": 89635, "eprint_status": "archive", "datestamp": "2023-08-20 06:19:17", "lastmod": "2023-10-18 22:53:05", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ledina-M-A", "name": { "family": "Ledina", "given": "M. A." } }, { "id": "Liang-Xuehai", "name": { "family": "Liang", "given": "X." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Y.-G." }, "orcid": "0000-0002-5936-6520" }, { "id": "Jung-Jin", "name": { "family": "Jung", "given": "J." } }, { "id": "Perdue-B", "name": { "family": "Perdue", "given": "B." } }, { "id": "Tsang-Chu-F", "name": { "family": "Tsang", "given": "C." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "M. P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Stickney-John-L", "name": { "family": "Stickney", "given": "J. L." } } ] }, "title": "Investigations into the Formation of Germanene Using Electrochemical Atomic Layer Deposition (E-ALD)", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 ECS - The Electrochemical Society. \n\nAcknowledgment is made to the NSF division of Materials Research, #1410109, for support of this research.", "abstract": "This paper will discuss possible formation of germanene electrochemically. Germanene should be a single layer allotrope of Ge. The techniques of in-situ electrochemical STM (EC-STM), voltammetry, coulometry, and micro-Raman have been used to investigate the electrochemical formation of germanene. Studies on Au(111) show that the initial deposition of Ge is kinetically slow and somewhat unstable, whereas the self-limited layer of Ge is stable and shows atomic distances of about 0.44 nm \u00b1 0.02 nm. Micro-Raman was performed on Ge nanofilms, but only displayed a shift near 290 cm^(-1) in one area. Given the STM results, it appears that the coherence of the germanene domains will need to be increased in order to more consistently produce the Raman signal. The data presented suggest that germanene has been formed electrochemically, although only as a minority species.", "date": "2015-05-16", "date_type": "published", "publication": "ECS Transactions", "volume": "66", "number": "6", "publisher": "Electrochemical Society", "pagerange": "129-140", "id_number": "CaltechAUTHORS:20180914-100810994", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20180914-100810994", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "DMR-1410109" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/06606.0129ecst", "pub_year": "2015", "author_list": "Ledina, M. A.; Liang, X.; et el." }, { "id": "https://authors.library.caltech.edu/records/sgp5c-41g13", "eprint_id": 72185, "eprint_status": "archive", "datestamp": "2023-08-20 06:19:03", "lastmod": "2023-10-23 18:01:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael Frankston" }, "orcid": "0000-0002-0710-7068" }, { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias Hermann" }, "orcid": "0000-0003-0091-2045" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Axnanda-S", "name": { "family": "Axnanda", "given": "S." } }, { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter" }, "orcid": "0000-0002-8693-4562" }, { "id": "Hussain-Z", "name": { "family": "Hussain", "given": "Z." } }, { "id": "Mayer-T", "name": { "family": "Mayer", "given": "Thomas" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce" }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Z." }, "orcid": "0000-0002-8968-7050" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Investigation of the Si/TiO_2/Electrolyte Interface Using Operando Tender X-ray Photoelectron Spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 ECS - The Electrochemical Society. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. We thank Dr. Philip Ross for contributions to the conceptual development of the AP-XPS end-station and experimental design.\n\nPublished - ECS_Trans.-2015-Lichterman-97-103.pdf
", "abstract": "Semiconductor-electrolyte interfaces allow for the creation of photoactive semiconductor systems that have band bending and other characteristics analogous to semiconductor-metal junctions (Schottky junctions). We demonstrate herein that XPS measurements can be obtained on a full three-electrode electrochemical system under potentiostatic control by use of tender X-rays to provide photoelectrons with sufficient kinetic energy to penetrate through a thin electrolyte overlayer on a portion of the working electrode. The response of the photoelectron binding energies to variations in applied voltage demonstrates that the XPS investigation works in an operando manner to elucidate the energetics of such interfaces.", "date": "2015-05-15", "date_type": "published", "publication": "ECS Transactions", "volume": "66", "number": "6", "publisher": "Electrochemical Society", "pagerange": "97-103", "id_number": "CaltechAUTHORS:20161121-082816017", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161121-082816017", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1149/06606.0097ecst", "primary_object": { "basename": "ECS_Trans.-2015-Lichterman-97-103.pdf", "url": "https://authors.library.caltech.edu/records/sgp5c-41g13/files/ECS_Trans.-2015-Lichterman-97-103.pdf" }, "pub_year": "2015", "author_list": "Lichterman, Michael Frankston; Richter, Matthias Hermann; et el." }, { "id": "https://authors.library.caltech.edu/records/qen0s-4t131", "eprint_id": 72186, "eprint_status": "archive", "datestamp": "2023-08-20 06:19:07", "lastmod": "2023-10-23 18:01:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Richter-M-H", "name": { "family": "Richter", "given": "Matthias Hermann" }, "orcid": "0000-0003-0091-2045" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael Frankston" }, "orcid": "0000-0002-0710-7068" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Crumlin-E-J", "name": { "family": "Crumlin", "given": "Ethan J." }, "orcid": "0000-0003-3132-190X" }, { "id": "Mayer-T", "name": { "family": "Mayer", "given": "Thomas" } }, { "id": "Axnanda-S", "name": { "family": "Axnanda", "given": "S." } }, { "id": "Favaro-M", "name": { "family": "Favaro", "given": "Marco" } }, { "id": "Drisdell-W-S", "name": { "family": "Drisdell", "given": "Walter" }, "orcid": "0000-0002-8693-4562" }, { "id": "Hussain-Z", "name": { "family": "Hussain", "given": "Z." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce" }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Liu-Zhu", "name": { "family": "Liu", "given": "Z." }, "orcid": "0000-0002-8968-7050" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Measurement of the Energy-Band Relations of Stabilized Si Photoanodes Using Operando Ambient Pressure X-ray Photoelectron Spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 ECS - The Electrochemical Society. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. The Advanced Light Source is supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE AC02 05CH11231. We acknowledge Dr. Philip Ross for contributions to the conceptual development of the AP-PES end station and experimental design. We acknowledge Fadl Saadi, Beomgyun Jeong, and Sana Rani for assistance during data collection at the beamline, Ravishankar Sundararaman for helpful discussions and assistance with theory, and Joseph A. Beardslee for assistance in XPS data collection.\n\nPublished - ECS_Trans.-2015-Richter-105-13.pdf
", "abstract": "The energy-band relations and electronic properties for the light absorber/protection-layer stack of TiO_2-stabilized Si photoanodes have been determined by ambient pressure x-ray synchrotron radiation photoelectron spectroscopy under an applied potential (operando), from single core-level emission lines. The experiments have also been complemented with laboratory-based monochromatic XPS data. Electrochemical parameters are additionally derived directly from x-ray photoemission data, and a method is presented to derive interface-state densities from such operando data.", "date": "2015-05-15", "date_type": "published", "publication": "ECS Transactions", "volume": "66", "number": "6", "publisher": "Electrochemical Society", "pagerange": "105-113", "id_number": "CaltechAUTHORS:20161121-083409878", "issn": "1938-6737", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20161121-083409878", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" }, { "id": "Kavli-Nanoscience-Institute" } ] }, "doi": "10.1149/06606.0105ecst", "primary_object": { "basename": "ECS_Trans.-2015-Richter-105-13.pdf", "url": "https://authors.library.caltech.edu/records/qen0s-4t131/files/ECS_Trans.-2015-Richter-105-13.pdf" }, "pub_year": "2015", "author_list": "Richter, Matthias Hermann; Lichterman, Michael Frankston; et el." }, { "id": "https://authors.library.caltech.edu/records/2jg0n-9c688", "eprint_id": 56993, "eprint_status": "archive", "datestamp": "2023-08-20 06:10:09", "lastmod": "2023-10-23 16:13:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Park-Sang-Hee", "name": { "family": "Park", "given": "Sang Hee" } }, { "id": "Warren-E-L", "name": { "family": "Warren", "given": "Emily L." }, "orcid": "0000-0001-8568-7881" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Unassisted solar-driven photoelectrosynthetic HI splitting using membrane-embedded Si microwire arrays", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 Royal Society of Chemistry.\n\nReceived 22 Jan 2015, Accepted 01 Apr 2015, First published online 01 Apr 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A. acknowledges support from a U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under the EERE Fuel Cell Technologies Program. The authors would like to thank Dan Turner\u2013Evans, Morgan Putnam, and Mike Kelzenberg for their generous assistance and donation of Si microwire array samples for some of the preliminary studies; Jacob Good for his assistance with the mass spectrometer; Rick P. Gerhart from the Caltech Glassblowing Shop for fabricating custom borosilicate electrochemical cells; Steve Olson and Mike Roy from the Caltech Machine Shop for fabricating custom free-standing\ndevice holders and a sample holder for the absorption spectrometer; and Harry Gray, Harry Atwater, and Bruce Brunschwig for useful discussions and guidance.\n\nPublished - c5ee00227c.pdf
Supplemental Material - c5ee00227c1_si.pdf
", "abstract": "Free-standing, membrane-embedded, Si microwire arrays have been used to affect the solar-driven, unassisted splitting of HI into H_2 and I_3\u2212. The Si microwire arrays were grown by a chemical-vapor-deposition vapor\u2013liquid\u2013solid growth process using Cu growth catalysts, with a radial n+p junction then formed on each microwire. A Nafion proton-exchange membrane was introduced between the microwires and Pt electrocatalysts were then photoelectrochemically deposited on the microwires. The composite Si/Pt\u2013Nafion membrane was mechanically removed from the growth substrate, and Pt electrocatalysts were then also deposited on the back side of the structure. The resulting membrane-bound Si microwire arrays spontaneously split concentrated HI into H_2(g) and I_3\u2212 under 1 Sun of simulated solar illumination. The reaction products (i.e. H_2 and I_3\u2212) were confirmed by mass spectrometry and ultraviolet\u2013visible electronic absorption spectroscopy.", "date": "2015-05-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "5", "publisher": "Royal Society of Chemistry", "pagerange": "1484-1492", "id_number": "CaltechAUTHORS:20150427-090213779", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150427-090213779", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c5ee00227c", "primary_object": { "basename": "c5ee00227c.pdf", "url": "https://authors.library.caltech.edu/records/2jg0n-9c688/files/c5ee00227c.pdf" }, "related_objects": [ { "basename": "c5ee00227c1_si.pdf", "url": "https://authors.library.caltech.edu/records/2jg0n-9c688/files/c5ee00227c1_si.pdf" } ], "pub_year": "2015", "author_list": "Ardo, Shane; Park, Sang Hee; et el." }, { "id": "https://authors.library.caltech.edu/records/gpyj8-yb095", "eprint_id": 57643, "eprint_status": "archive", "datestamp": "2023-08-22 15:23:51", "lastmod": "2023-10-23 17:35:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yan-Qimin", "name": { "family": "Yan", "given": "Qimin" } }, { "id": "Li-Guo", "name": { "family": "Li", "given": "Guo" } }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Yu-Jie", "name": { "family": "Yu", "given": "Jie" } }, { "id": "Persson-K-A", "name": { "family": "Persson", "given": "Kristin A." }, "orcid": "0000-0003-2495-5509" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Neaton-J-B", "name": { "family": "Neaton", "given": "Jeffrey B." }, "orcid": "0000-0001-7585-6135" } ] }, "title": "Mn_2V_2O_7: An Earth Abundant Light Absorber for Solar Water Splitting", "ispublished": "pub", "full_text_status": "public", "keywords": "band structure; metal oxide; Mn2V2O7; photocatalysts; solar water splitting; density functional theory", "note": "\u00a9 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: October 17, 2014; Revised: November 27, 2014; Published online: January 21, 2015.\n\nComputational work was supported by the Materials Project Predictive Modeling Center (EDCBEE) through the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02\u201305CH11231. Experimental work was performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). Work at the Molecular Foundry was supported by the Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy under Contract No. DE-AC02\u201305CH11231. Computational resources also provided by the Department of Energy through the National Energy Supercomputing Center. The authors thank Dan Guevarra and Aniketa Shinde for assistance with acquisition of the photocurrent data and Chengxiang Xiang, Slobodan Mitrovic and Joel Haber for helpful discussions.\n\nSupplemental Material - aenm201401840-sup-0001-S1.pdf
", "abstract": "Complex oxide \u03b2-Mn_2V_2O_7 is identified as exhibiting near-optimal band energetics for solar fuel applications among known metal oxides. Experiments, corroborated by theory, indicate a bandgap near 1.8 eV. The calculations predict that \u03b2-Mn_2V_2O_7 has well-aligned band edge energies for the hydrogen evolution reaction and oxygen evolution reaction. Photoelectrochemical measurements indicate appreciable photocurrent, corroborating the predictions.", "date": "2015-04-22", "date_type": "published", "publication": "Advanced Energy Materials", "volume": "5", "number": "8", "publisher": "Wiley", "pagerange": "Art. No. 1401840", "id_number": "CaltechAUTHORS:20150519-092604842", "issn": "1614-6832", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150519-092604842", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02\u201305CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/aenm.201401840", "primary_object": { "basename": "aenm201401840-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/gpyj8-yb095/files/aenm201401840-sup-0001-S1.pdf" }, "pub_year": "2015", "author_list": "Yan, Qimin; Li, Guo; et el." }, { "id": "https://authors.library.caltech.edu/records/bcav9-7ms84", "eprint_id": 58389, "eprint_status": "archive", "datestamp": "2023-08-20 05:48:23", "lastmod": "2023-10-23 19:18:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Luca-O-R", "name": { "family": "Luca", "given": "Oana R." }, "orcid": "0000-0002-2988-4909" }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Dalleska-N-F", "name": { "family": "Dalleska", "given": "Nathan F." }, "orcid": "0000-0002-2059-1587" }, { "id": "Koval-C-A", "name": { "family": "Koval", "given": "Carl A." } } ] }, "title": "The Selective Electrochemical Conversion of Preactivated CO_2 to Methane", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Author(s). Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. \n\nManuscript submitted February 9, 2015; revised manuscript received March 24, 2015. Published April 14, 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U. S. Department of Energy under Award Number DE-SC0004993. The authors thank Professors Jonas Peters, T. Don Tilley, Clifford Kubiak and Nathan Lewis for many insightful discussions. We thank Dr. Slobodan Mitrovic and Natalie Becerra for help with the XPS analyses, Ryan Jones and Katherine Schilling for technical support and Rick Gerhardt for help with the electrochemical cell design. ORL and CCLM performed electrochemical experiments. CCLM analyzed the XPS data, NFD aided in the labeling experiments. CAK advised the research. ORL had the idea for the project. ORL, CCLM, NFD and CAK wrote the manuscript.\n\nPublished - J._Electrochem._Soc.-2015-Luca-H473-6.pdf
Supplemental Material - 14874_1_supp_0_nlrxfz.txt
Supplemental Material - 14874_1_supp_217874_nlqd0x.pdf
", "abstract": "This work reports the selective electrochemical conversion of CO_2 to methane, the reverse reaction of fossil fuel combustion. This reaction is facilitated by preactivation of the CO_2 molecule with an N-heterocyclic carbene (NHC) to form a zwitterionic species in the first step. In the presence of Ni(cyclam)^(2+) and CF_3CH_2OH, this species is shown to undergo further electrochemical reduction of the bound-CO_2 fragment at glassy carbon cathodes in dichloromethane electrolyte solution. Labeling studies confirm the origin of the carbon and protons in the methane product are the preactivated CO_2 and trifluoroethanol respectively.", "date": "2015-04-14", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "162", "number": "7", "publisher": "Electrochemical Society", "pagerange": "H473-H476", "id_number": "CaltechAUTHORS:20150622-081748039", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150622-081748039", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.0371507jes", "primary_object": { "basename": "14874_1_supp_0_nlrxfz.txt", "url": "https://authors.library.caltech.edu/records/bcav9-7ms84/files/14874_1_supp_0_nlrxfz.txt" }, "related_objects": [ { "basename": "14874_1_supp_217874_nlqd0x.pdf", "url": "https://authors.library.caltech.edu/records/bcav9-7ms84/files/14874_1_supp_217874_nlqd0x.pdf" }, { "basename": "J._Electrochem._Soc.-2015-Luca-H473-6.pdf", "url": "https://authors.library.caltech.edu/records/bcav9-7ms84/files/J._Electrochem._Soc.-2015-Luca-H473-6.pdf" } ], "pub_year": "2015", "author_list": "Luca, Oana R.; McCrory, Charles C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/9hdcw-5f261", "eprint_id": 56238, "eprint_status": "archive", "datestamp": "2023-08-20 05:46:37", "lastmod": "2023-10-23 15:12:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Ferrer-I-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Chatman-S-M", "name": { "family": "Chatman", "given": "Shawn M." }, "orcid": "0000-0002-7951-5968" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "Benchmarking Hydrogen Evolving Reaction and Oxygen Evolving Reaction Electrocatalysts for Solar Water Splitting Devices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: October 10, 2014. Publication Date (Web): February 10, 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We thank Joel Haber for providing the NiFeCoCe-(a) and NiFeCoCe-(b) samples and Jesus M. Velazquez for his help in preparing the sputtered Ir and Ru-(b) samples. We also thank Slobodan Mitrovic, Natalie Becerra, and Fadl Saadi for their help with the collection of XPS data. In addition, we acknowledge many useful discussions with Nathan S. Lewis and Carl A. Koval.\n\nSupplemental Material - ja510442p_si_001.pdf
", "abstract": "Objective comparisons of electrocatalyst activity and stability using standard methods under identical conditions are necessary to evaluate the viability of existing electrocatalysts for integration into solar-fuel devices as well as to help inform the development of new catalytic systems. Herein, we use a standard protocol as a primary screen for evaluating the activity, short-term (2 h) stability, and electrochemically active surface area (ECSA) of 18 electrocatalysts for the hydrogen evolution reaction (HER) and 26 electrocatalysts for the oxygen evolution reaction (OER) under conditions relevant to an integrated solar water-splitting device in aqueous acidic or alkaline solution. Our primary figure of merit is the overpotential necessary to achieve a magnitude current density of 10 mA cm^(\u20132) per geometric area, the approximate current density expected for a 10% efficient solar-to-fuels conversion device under 1 sun illumination. The specific activity per ECSA of each material is also reported. Among HER catalysts, several could operate at 10 mA cm^(\u20132) with overpotentials <0.1 V in acidic and/or alkaline solutions. Among OER catalysts in acidic solution, no non-noble metal based materials showed promising activity and stability, whereas in alkaline solution many OER catalysts performed with similar activity achieving 10 mA cm\u20132 current densities at overpotentials of \u223c0.33\u20130.5 V. Most OER catalysts showed comparable or better specific activity per ECSA when compared to Ir and Ru catalysts in alkaline solutions, while most HER catalysts showed much lower specific activity than Pt in both acidic and alkaline solutions. For select catalysts, additional secondary screening measurements were conducted including Faradaic efficiency and extended stability measurements.", "date": "2015-04-08", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "137", "number": "13", "publisher": "American Chemical Society", "pagerange": "4347-4357", "id_number": "CaltechAUTHORS:20150331-092334778", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150331-092334778", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ja510442p", "primary_object": { "basename": "ja510442p_si_001.pdf", "url": "https://authors.library.caltech.edu/records/9hdcw-5f261/files/ja510442p_si_001.pdf" }, "pub_year": "2015", "author_list": "McCrory, Charles C. L.; Jung, Suho; et el." }, { "id": "https://authors.library.caltech.edu/records/rvhv0-kz121", "eprint_id": 57361, "eprint_status": "archive", "datestamp": "2023-08-20 05:37:56", "lastmod": "2023-10-23 17:18:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Niu-Kai-Yang", "name": { "family": "Niu", "given": "Kai-Yang" } }, { "id": "Lin-Feng", "name": { "family": "Lin", "given": "Feng" } }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Fang-Lian", "name": { "family": "Fang", "given": "Lian" } }, { "id": "Nordlund-D", "name": { "family": "Nordlund", "given": "Dennis" } }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Weng-Tsu-Chien", "name": { "family": "Weng", "given": "Tsu-Chien" } }, { "id": "Ercius-P", "name": { "family": "Ercius", "given": "Peter" } }, { "id": "Doeff-M-M", "name": { "family": "Doeff", "given": "Marca M." } }, { "id": "Zheng-Haimei", "name": { "family": "Zheng", "given": "Haimei" } } ] }, "title": "Tuning Complex Transition Metal Hydroxide Nanostructures as Active Catalysts for Water Oxidation by a Laser\u2212Chemical Route", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society. \n\nReceived: January 4, 2015. Revised: February 11, 2015. Publication Date (Web): February 27, 2015. \n\nWe thank Prof. Alexis T. Bell and Dr. Mary W. Louie for useful discussions. We performed TEM characterization using Tecnai, TitanX, and TEAM1 microscopes at National Center for Electron Microscopy of the Molecular Foundry at Lawrence Berkeley National Laboratory (LBNL), which is supported by the U.S. Department of Energy (DOE) Office of Basic Energy Sciences under Contract No. DE-AC02-05CH11231. The synchrotron X-ray portions of this research were carried out at the Stanford Synchrotron Radiation Lightsource (Beamlines 10-1 and 8-2), a Directorate of SLAC National Accelerator Laboratory and an Office of Science User Facility operated for the U.S. Department of Energy Office of Science at Stanford University. Electrochemical measurements are based on work performed at the Joint Center for Artificial Photosynthesis, a DOE Innovation Hub, supported through the Office of Science of the U.S. DOE under Award No. DE-SC0004993. K.N. acknowledges Dr. Renjia Zhou for performing the TGA, FT-IR in Molecular Foundry and Dr. Xin Liu at LBNL for measuring the UV\u2212vis absorption spectra. L.F. acknowledges the support of China Scholarship Council (CSC) under No. 2010850533 and the National Basic Research Program of China (2014CB931700). F.L., D.N., and T.-C.W. thank Dr. Jun-Sik Lee and Glen Kerr for the help at SSRL Beamline 8-2. H.Z. acknowledges the SinBeRise program of BEARS at University of California, Berkeley for travel support. She also thanks the support of DOE Office of Science Early Career Research Program.\n\nSupplemental Material - nl5b00026_si_001.pdf
", "abstract": "Diverse transition metal hydroxide nanostructures were synthesized by laser-induced hydrolysis in a liquid precursor solution for alkaline oxygen evolution reaction (OER). Several active OER catalysts with fine control of composition, structure, and valence state were obtained including (Li_x)[Ni_(0.66)Mn_(0.34)(OH)_2](NO_3)(CO_3) \u00b7 mH_2O, Li_x[Ni_(0.67)Co_(0.33)(OH)_2](NO_3)_(0.25)(ORO)_(0.35) \u00b7 mH_2O, etc. An operate overpotential less than 0.34 V at current density of 10 mA cm^(\u20132) was achieved. Such a controllable laser\u2013chemical route for assessing complex nanostructures in liquids opens many opportunities to design novel functional materials for advanced applications.", "date": "2015-04", "date_type": "published", "publication": "Nano Letters", "volume": "15", "number": "4", "publisher": "American Chemical Society", "pagerange": "2498-2503", "id_number": "CaltechAUTHORS:20150508-071809496", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150508-071809496", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "China Scholarship Council (CSC)", "grant_number": "2010850533" }, { "agency": "National Basic Research Program of China", "grant_number": "2014CB931700" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/acs.nanolett.5b00026", "primary_object": { "basename": "nl5b00026_si_001.pdf", "url": "https://authors.library.caltech.edu/records/rvhv0-kz121/files/nl5b00026_si_001.pdf" }, "pub_year": "2015", "author_list": "Niu, Kai-Yang; Lin, Feng; et el." }, { "id": "https://authors.library.caltech.edu/records/6j33r-th623", "eprint_id": 55626, "eprint_status": "archive", "datestamp": "2023-08-20 05:35:28", "lastmod": "2023-10-20 22:26:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Generating Information-Rich High-Throughput Experimental Materials Genomes using Functional Clustering via Multitree Genetic Programming and Information Theory", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: October 9, 2014; Revised: February 23, 2015; Publication Date (Web): February 23, 2015.\n\nThis work is performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC000499. This research used resources of the National Energy Research Scientific Computing Center, a DOE Office of Science User Facility supported by the Office of Science of the U.S. Department of Energy under Contract No. DE-AC02-05CH11231. The authors thank Dr. Misha Z. Pesenson for helpful discussions.\n\nSupplemental Material - co5001579_si_001.pdf
", "abstract": "High-throughput experimental methodologies are capable of synthesizing, screening and characterizing vast arrays of combinatorial material libraries at a very rapid rate. These methodologies strategically employ tiered screening wherein the number of compositions screened decreases as the complexity, and very often the scientific information obtained from a screening experiment, increases. The algorithm used for down-selection of samples from higher throughput screening experiment to a lower throughput screening experiment is vital in achieving information-rich experimental materials genomes. The fundamental science of material discovery lies in the establishment of composition\u2013structure\u2013property relationships, motivating the development of advanced down-selection algorithms which consider the information value of the selected compositions, as opposed to simply selecting the best performing compositions from a high throughput experiment. Identification of property fields (composition regions with distinct composition-property relationships) in high throughput data enables down-selection algorithms to employ advanced selection strategies, such as the selection of representative compositions from each field or selection of compositions that span the composition space of the highest performing field. Such strategies would greatly enhance the generation of data-driven discoveries. We introduce an informatics-based clustering of composition-property functional relationships using a combination of information theory and multitree genetic programming concepts for identification of property fields in a composition library. We demonstrate our approach using a complex synthetic composition-property map for a 5 at. % step ternary library consisting of four distinct property fields and finally explore the application of this methodology for capturing relationships between composition and catalytic activity for the oxygen evolution reaction for 5429 catalyst compositions in a (Ni\u2013Fe\u2013Co\u2013Ce)O_x library.", "date": "2015-04", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "17", "number": "4", "publisher": "American Chemical Society", "pagerange": "224-233", "id_number": "CaltechAUTHORS:20150309-091323359", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150309-091323359", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/co5001579", "primary_object": { "basename": "co5001579_si_001.pdf", "url": "https://authors.library.caltech.edu/records/6j33r-th623/files/co5001579_si_001.pdf" }, "pub_year": "2015", "author_list": "Suram, Santosh K.; Haber, Joel A.; et el." }, { "id": "https://authors.library.caltech.edu/records/0xnhm-6wk36", "eprint_id": 55703, "eprint_status": "archive", "datestamp": "2023-08-22 15:12:53", "lastmod": "2023-10-20 22:59:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Hale-William-G", "name": { "family": "Hale", "given": "William G." } }, { "id": "Wang-Hsin-Ping", "name": { "family": "Wang", "given": "Hsin-Ping" } }, { "id": "Zhou-Xinghao", "name": { "family": "Zhou", "given": "Xinghao" }, "orcid": "0000-0001-9229-7670" }, { "id": "Plymale-Noah-T", "name": { "family": "Plymale", "given": "Noah T." }, "orcid": "0000-0003-2564-8009" }, { "id": "Omelchenko-Stefan-T", "name": { "family": "Omelchenko", "given": "Stefan T." }, "orcid": "0000-0003-1104-9291" }, { "id": "He-Jr-Hau", "name": { "family": "He", "given": "Jr-Hau" } }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stable solar-driven oxidation of water by semiconducting photoanodes protected by transparent catalytic nickel oxide films", "ispublished": "pub", "full_text_status": "public", "keywords": "electrocatalysis; solar-driven water oxidation; photoanode stabilization; nickel oxide", "note": "\u00a9 2015 National Academy of Sciences. \n\nEdited by Michael L. Klein, Temple University, Philadelphia, PA, and approved February 10, 2015 (received for review December 3, 2014). Published online before print March 11, 2015, doi: 10.1073/pnas.1423034112 \n\nThis material is based on work performed by the Joint Center for Artificial Photosynthesis, a Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the US DOE under Award DE-SC0004993. N.T.P. acknowledges support from the Graduate Research Fellowship Program of the US National Science Foundation. B.S.B. was supported by the Beckman Institute of the California Institute of Technology. This work was also supported by the Gordon and Betty Moore Foundation under Award GBMF1225.\n\nAuthor contributions: K.S. and N.S.L. designed research; K.S., F.H.S., M.F.L., W.G.H., H.-P.W., X.Z., N.T.P., and S.T.O. performed research; K.S., B.S.B., and N.S.L. analyzed data; and K.S., J.-H.H., K.M.P., B.S.B., and N.S.L. wrote the paper. \n\nThe authors declare no conflict of interest. \n\nThis article is a PNAS Direct Submission. \n\nThis article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1423034112/-/DCSupplemental.\n\nPublished - 3612.full.pdf
Supplemental Material - pnas.1423034112.sapp.pdf
", "abstract": "Reactively sputtered nickel oxide (NiO_x) films provide transparent, antireflective, electrically conductive, chemically stable coatings that also are highly active electrocatalysts for the oxidation of water to O_2(g). These NiO_x coatings provide protective layers on a variety of technologically important semiconducting photoanodes, including textured crystalline Si passivated by amorphous silicon, crystalline n-type cadmium telluride, and hydrogenated amorphous silicon. Under anodic operation in 1.0 M aqueous potassium hydroxide (pH 14) in the presence of simulated sunlight, the NiO_x films stabilized all of these self-passivating, high-efficiency semiconducting photoelectrodes for >100 h of sustained, quantitative solar-driven oxidation of water to O_2(g).", "date": "2015-03-24", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "112", "number": "12", "publisher": "National Academy of Sciences", "pagerange": "3612-3617", "id_number": "CaltechAUTHORS:20150311-121532251", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150311-121532251", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Caltech Beckman Institute" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1423034112", "pmcid": "PMC4378389", "primary_object": { "basename": "pnas.1423034112.sapp.pdf", "url": "https://authors.library.caltech.edu/records/0xnhm-6wk36/files/pnas.1423034112.sapp.pdf" }, "related_objects": [ { "basename": "3612.full.pdf", "url": "https://authors.library.caltech.edu/records/0xnhm-6wk36/files/3612.full.pdf" } ], "pub_year": "2015", "author_list": "Sun, Ke; Saadi, Fadl H.; et el." }, { "id": "https://authors.library.caltech.edu/records/cp2rh-mc727", "eprint_id": 57103, "eprint_status": "archive", "datestamp": "2023-08-20 05:18:39", "lastmod": "2023-10-23 17:04:19", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A sensitivity analysis to assess the relative importance of improvements in electrocatalysts, light absorbers, and system geometry on the efficiency of solar-fuels generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry.\n\nReceived 23 Jul 2014, Accepted 23 Dec 2014, First published online 24 Dec 2014.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award number DE-SC0004993.\n\nPublished - c4ee02314e.pdf
", "abstract": "A sensitivity analysis has been performed for a variety of generic designs for solar-fuels generators. The analysis has revealed the relative importance of reductions in the overpotentials of electrocatalysts, of improvements in the materials properties of light absorbers, and of optimization in the system geometry for various different types of solar-fuels generators, while considering operation at a range of temperatures as well as under a variety of illumination intensities including up to 10-fold optical concentration.", "date": "2015-03-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "3", "publisher": "Royal Society of Chemistry", "pagerange": "876-886", "id_number": "CaltechAUTHORS:20150430-084157336", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150430-084157336", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c4ee02314e", "primary_object": { "basename": "c4ee02314e.pdf", "url": "https://authors.library.caltech.edu/records/cp2rh-mc727/files/c4ee02314e.pdf" }, "pub_year": "2015", "author_list": "Chen, Yikai; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/n2j8e-cz079", "eprint_id": 55967, "eprint_status": "archive", "datestamp": "2023-08-20 05:05:53", "lastmod": "2023-10-20 23:29:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Zhou-Lan", "name": { "family": "Zhou", "given": "Lan" }, "orcid": "0000-0002-7052-266X" }, { "id": "Becerra-Stasiewicz-N", "name": { "family": "Becerra-Stasiewicz", "given": "Natalie" } }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "Kevin" } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Kendrick-B-M", "name": { "family": "Kendrick", "given": "Brian M." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Combinatorial thin film composition mapping using three dimensional deposition profiles", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 AIP Publishing LLC.\n\nReceived 28 January 2015; accepted 26 February 2015; published online 17 March 2015.\n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Ryan R. J. Jones for assistance with chamber schematics, Frances Houle for insightful discussions, and Aniketa Shinde for assistance with the preparation of the manuscript.\n\nPublished - 1.4914466.pdf
", "abstract": "Many next-generation technologies are limited by material performance, leading to increased interest in the discovery of advanced materials using combinatorial synthesis, characterization, and screening. Several combinatorial synthesis techniques, such as solution based methods, advanced manufacturing, and physical vapor deposition, are currently being employed for various applications. In particular, combinatorial magnetron sputtering is a versatile technique that provides synthesis of high-quality thin film composition libraries. Spatially addressing the composition of these thin films generally requires elemental quantification measurements using techniques such as energy-dispersive X-ray spectroscopy or X-ray fluorescence spectroscopy. Since these measurements are performed ex-situ and post-deposition, they are unable to provide real-time design of experiments, a capability that is required for rapid synthesis of a specific composition library. By using three quartz crystal monitors attached to a stage with translational and rotational degrees of freedom, we measure three-dimensional deposition profiles of deposition sources whose tilt with respect to the substrate is robotically controlled. We exhibit the utility of deposition profiles and tilt control to optimize the deposition geometry for specific combinatorial synthesis experiments.", "date": "2015-03", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "86", "number": "3", "publisher": "American Institute of Physics", "pagerange": "Art. No. 033904", "id_number": "CaltechAUTHORS:20150323-110035126", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150323-110035126", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4914466", "primary_object": { "basename": "1.4914466.pdf", "url": "https://authors.library.caltech.edu/records/n2j8e-cz079/files/1.4914466.pdf" }, "pub_year": "2015", "author_list": "Suram, Santosh K.; Zhou, Lan; et el." }, { "id": "https://authors.library.caltech.edu/records/akdbc-km770", "eprint_id": 51828, "eprint_status": "archive", "datestamp": "2023-08-22 15:01:49", "lastmod": "2023-10-18 18:00:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Becerra-Stasiewicz-N", "name": { "family": "Becerra-Stasiewicz", "given": "Natalie" } }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High-Throughput Screening for Acid-Stable Oxygen Evolution Electrocatalysts in the (Mn\u2013Co\u2013Ta\u2013Sb)O_x Composition Space", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Solar fuels; Water splitting; High throughput; Oxygen evolution; Electrochemical stability", "note": "\u00a9 2014 Springer Science+Business Media New York. \n\nPublished online: 7 November 2014. \n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Dr. Chengxiang Xiang for assistance with establishing the electrochemical treatment system and Dr. Manuel Soriaga for the illuminating discussions.", "abstract": "Solar generation of fuel is a promising future energy technology, and strong acidic conditions are highly desirable for integrated solar hydrogen generators. In particular, water splitting near pH 0 is attractive due to the availability of high theoretical efficiency, high performance hydrogen evolution catalysts, and robust ion exchange membranes. The lack of a stable, earth-abundant oxygen evolution catalyst inhibits deployment of this technology, and development of such a material is hampered by the strong anti-correlation between electrochemical stability and catalytic activity of non-precious metal oxides. High-throughput screening of mixed metal oxides offers a promising route to the identification of new stable catalysts and requires careful design of experiments to combine the concepts of rapid experimentation and long-term stability. By combining serial and parallel measurement techniques, we have created a high-throughput platform to assess the catalytic activity of material libraries in the as-prepared state and after 2 h of operation. By screening the entire (Mn\u2013Co\u2013Ta\u2013Sb)O_x composition space, we observe that the compositions with highest initial activity comprised cobalt and manganese oxides, but combinations with antimony and tantalum offer improved stability. By combining the desired properties of catalytic activity and stability, the optimal composition regions are readily identified, demonstrating the success and fidelity of this novel high-throughput screening platform.", "date": "2015-03", "date_type": "published", "publication": "Electrocatalysis", "volume": "6", "number": "2", "publisher": "Springer", "pagerange": "229-236", "id_number": "CaltechAUTHORS:20141117-094914554", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141117-094914554", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-014-0237-7", "pub_year": "2015", "author_list": "Shinde, Aniketa; Jones, Ryan J. R.; et el." }, { "id": "https://authors.library.caltech.edu/records/xs69e-xea25", "eprint_id": 53860, "eprint_status": "archive", "datestamp": "2023-08-22 15:02:06", "lastmod": "2023-10-19 22:18:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "Edwin" } }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Colorimetric Screening for High-Throughput Discovery of Light Absorbers", "ispublished": "pub", "full_text_status": "public", "keywords": "high-throughput; colorimetry; light absorbers; solar fuels", "note": "\u00a9 2014 American Chemical Society.\n\nReceived: October 2, 2014; revised: December 9, 2014. Published: December 30, 2014. \n\nThe authors thank Ryan J. R. Jones for assistance with the experiments. This manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (award no. DE-SC0004993).\n\nSupplemental Material - co500151u_si_001.pdf
", "abstract": "High-throughput screening is a powerful approach for identifying new functional materials in unexplored material spaces. With library synthesis capable of producing 10^5 to 10^6 samples per day, methods for material screening at rates greater than 1 Hz must be developed. For the discovery of new solar light absorbers, this throughput cannot be attained using standard instrumentation. Screening certain properties, such as the bandgap, are of interest only for phase pure materials, which comprise a small fraction of the samples in a typical solid-state material library. We demonstrate the utility of colorimetric screening based on processing photoscanned images of combinatorial libraries to quickly identify distinct phase regions, isolate samples with desired bandgap, and qualitatively identify samples that are suitable for complementary measurements. Using multiple quaternary oxide libraries containing thousands of materials, we compare colorimetric screening and UV\u2013vis spectroscopy results, demonstrating successful identification of compounds with bandgap suitable for solar applications.", "date": "2015-03", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "17", "number": "3", "publisher": "American Chemical Society", "pagerange": "176-181", "id_number": "CaltechAUTHORS:20150120-090415724", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150120-090415724", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/co500151u", "primary_object": { "basename": "co500151u_si_001.pdf", "url": "https://authors.library.caltech.edu/records/xs69e-xea25/files/co500151u_si_001.pdf" }, "pub_year": "2015", "author_list": "Mitrovic, Slobodan; Soedarmadji, Edwin; et el." }, { "id": "https://authors.library.caltech.edu/records/1f716-40868", "eprint_id": 54306, "eprint_status": "archive", "datestamp": "2023-08-20 05:04:53", "lastmod": "2023-10-20 15:48:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Chmielowiec-Brian", "name": { "family": "Chmielowiec", "given": "Brian" }, "orcid": "0000-0002-3004-9345" }, { "id": "Sanabria-Chinchilla-Jean", "name": { "family": "Sanabria-Chinchilla", "given": "Jean" } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "A DEMS Study of the Reduction of CO_2, CO, and HCHO Pre-Adsorbed on Cu Electrodes: Empirical Inferences on the CO_2RR Mechanism", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2015 Springer Science+Business Media New York. Published online 27 Jan 2015.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993.", "abstract": "The effective abatement of atmospheric carbon through its conversion via electrochemical reduction to pure and oxygenated hydrocarbon fuels relies on the ability to control product selectivity at viable current densities and faradaic efficiencies. One critical aspect is the choice of the electrode and, in the CO_2-reduction electrocatalyst landscape, copper sits as the only metal known to deliver a remarkable variety of reduction products other than carbon monoxide and formic acid. However, much better catalyst performance is needed. The overall energy efficiency of copper is less than 40 %, and its nominal overvoltage at benchmark current densities remains unacceptably large at ca. 1 V. The diversity of the product distribution also becomes a major inconvenience in the likelihood that only one product is desired; unless, of course, if the selectivity window for such product is already known. Several experimental parameters influence the product selectivity of the CO_2 reduction reactions (hereafter referred to as CO_2RR); the more obvious include the composition and the crystal structure of the catalyst surface, the applied potential, the solution pH, and the supporting electrolyte. The documentation, at the atomic level, of the mechanistic origins of the CO_2RR selectivity of copper demands a systematic combination of ex situ, in situ, and operando techniques to interrogate the electrode surface, pristine and modified, prior to, during, and after the reduction reaction; the task includes not only the analysis of reaction-product distributions but also the identification of surface intermediates that serve as the precursor states for each reaction pathway.\nWe recently studied the nature of well-defined Cu(hkl) single-crystal surfaces that, similar to \"real-world\" catalysts, were handled in air. Such investigation is pertinent since Cu is a well-known scavenger of molecular oxygen; hence, CO_2RR electrocatalysis must first contend with the initial presence of multilayers of disordered copper oxides. It was found that the oxides are actually easily reduced electrochemically back to the metal; in addition, even if the oxided single-crystal surface is severely disordered, cathodic reduction completely regenerates the original ordered structure. Most recently, we discovered that a polycrystalline Cu electrode held at a fixed negative potential in the CO_2RR region in KOH, undergoes stepwise surface reconstruction, first to Cu(111) and then to Cu(100). The results help explain the Cu(100)-like behavior of Cu(pc) in terms of CO_2RR product selectivity.\nIn the work described in this Letter, we have applied differential electrochemical mass spectrometry (DEMS) of pre-adsorbed reactants and intermediates as a complementary experimental approach in the study of the mechanistic pathways for the Cu-catalyzed CO_2 reduction reactions; the reactant was CO_2 and the intermediates were CO and HCHO. The reduction products monitored by mass spectrometry were H_2, CO (from CO_2), CH_4, H_2C=CH_2 and CH_3CH_2OH.", "date": "2015-03", "date_type": "published", "publication": "Electrocatalysis", "volume": "6", "number": "2", "publisher": "Springer", "pagerange": "127-131", "id_number": "CaltechAUTHORS:20150202-141003348", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150202-141003348", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-015-0246-1", "pub_year": "2015", "author_list": "Javier, Alnald; Chmielowiec, Brian; et el." }, { "id": "https://authors.library.caltech.edu/records/sp33p-jrc73", "eprint_id": 56043, "eprint_status": "archive", "datestamp": "2023-08-20 05:03:40", "lastmod": "2023-10-20 23:35:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Digdaya-I-A", "name": { "family": "Digdaya", "given": "Ibadillah A." } }, { "id": "Buijs-T-W-F", "name": { "family": "Buijs", "given": "Thom W. F." } }, { "id": "Abdi-F-F", "name": { "family": "Abdi", "given": "Fatwa F." } }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Dam-B", "name": { "family": "Dam", "given": "Bernard" } }, { "id": "Zeman-M", "name": { "family": "Zeman", "given": "Miro" } }, { "id": "Smith-W-A", "name": { "family": "Smith", "given": "Wilson A." } }, { "id": "Smets-A-H-M", "name": { "family": "Smets", "given": "Arno H. M." } } ] }, "title": "Gradient dopant profiling and spectral utilization of monolithic thin-film silicon photoelectrochemical tandem devices for solar water splitting", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Royal Society of Chemistry. Received 15th October 2014. Accepted 13th November 2014. First published online 13 Nov 2014.\n\nThe authors would like to thank Guangtao Yang from PVMD group in TU Delft for assistance with substrate preparation, Dr Feng Zhu from MVSystems Inc. and Dr Bruce S. Brunschwig from the Molecular Materials Research Center (MMRC) at California Institute of Technology for helpful scientific discussions. Financial support from the VIDI project (granted to Dr A. H. M. Smets) by NWO-STW is gratefully acknowledged. This research is financed in part by the BioSolar Cells open innovation consortium (W. A. Smith and I. A. Digdaya), supported by the Dutch Ministry of Economic Affairs, Agriculture and Innovation. Z. Huang and R. Liu are supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nPublished - c4ta05523c.pdf
Supplemental Material - c4ta05523c1.pdf
", "abstract": "A cost-effective and earth-abundant photocathode based on hydrogenated amorphous silicon carbide (a-SiC:H) is demonstrated to split water into hydrogen and oxygen using solar energy. A monolithic a-SiC:H photoelectrochemical (PEC) cathode integrated with a hydrogenated amorphous silicon (a-SiC:H)/nano-crystalline silicon (nc-Si:H) double photovoltaic (PV) junction achieved a current density of \u22125.1 mA cm^(\u22122) at 0 V versus the reversible hydrogen electrode. The a-SiC:H photocathode used no hydrogen-evolution catalyst and the high current density was obtained using gradient boron doping. The growth of high quality nc-Si:H PV junctions in combination with optimized spectral utilization was achieved using glass substrates with integrated micro-textured photonic structures. The performance of the PEC/PV cathode was analyzed by simulations using Advanced Semiconductor Analysis (ASA) software.", "date": "2015-02-28", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "3", "number": "8", "publisher": "Royal Society of Chemistry", "pagerange": "4155-4162", "id_number": "CaltechAUTHORS:20150324-151230776", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150324-151230776", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" }, { "agency": "BioSolar Cells" }, { "agency": "Dutch Ministry of Economic Affairs, Agriculture and Innovation" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C4TA05523C", "primary_object": { "basename": "c4ta05523c.pdf", "url": "https://authors.library.caltech.edu/records/sp33p-jrc73/files/c4ta05523c.pdf" }, "related_objects": [ { "basename": "c4ta05523c1.pdf", "url": "https://authors.library.caltech.edu/records/sp33p-jrc73/files/c4ta05523c1.pdf" } ], "pub_year": "2015", "author_list": "Han, Lihao; Digdaya, Ibadillah A.; et el." }, { "id": "https://authors.library.caltech.edu/records/ft6sa-gk325", "eprint_id": 54285, "eprint_status": "archive", "datestamp": "2023-08-22 14:58:29", "lastmod": "2023-10-20 15:46:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Nielander-A-C", "name": { "family": "Nielander", "given": "Adam C." }, "orcid": "0000-0002-3639-2427" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Yang-Fan", "name": { "family": "Yang", "given": "Fan" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stable Solar-Driven Water Oxidation to O_2(g) by Ni-Oxide-Coated Silicon Photoanodes", "ispublished": "pub", "full_text_status": "public", "keywords": "semiconductors; photoanodes; solar-fuels; water-splitting", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: December 11, 2014; accepted: January 19.\n\nThis work was supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DESC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. UV\u2212vis spectroscopy and atomic-force microscopy were performed at the Molecular Materials Research Center (MMRC) in the Beckman Institute at the California Institute of Technology. B.S.B. was supported by the Beckman Institute of the California Institute of Technology. A.C.N. was supported by a Graduate Research Fellowship from the National Science Foundation. M.R.S. was supported by a graduate fellowship from the Resnick Sustainability Institute. This work was additionally supported by the Gordon and Betty Moore Foundation under Award No. GBMF1225. We thank K. Walczak for providing the FTO coated np+-Si(100) samples, C. Koval, R. Liu, and M. Lichterman for stimulating discussions, N. Becerra and L. Zhou for their assistance with XRD measurements, and K. Papadantonakis for assistance with editing this manuscript.\n\nSupplemental Material - jz5026195_si_001.pdf
", "abstract": "Semiconductors with small band gaps (<2 eV) must be stabilized against corrosion or passivation in aqueous electrolytes before such materials can be used as photoelectrodes to directly produce fuels from sunlight. In addition, incorporation of electrocatalysts on the surface of photoelectrodes is required for efficient oxidation of H_2O to O_2(g) and reduction of H_2O or H_2O and CO_2 to fuels. We report herein the stabilization of np^+-Si(100) and n-Si(111) photoanodes for over 1200 h of continuous light-driven evolution of O_2(g) in 1.0 M KOH(aq) by an earth-abundant, optically transparent, electrocatalytic, stable, conducting nickel oxide layer. Under simulated solar illumination and with optimized index-matching for proper antireflection, NiO_x-coated np+-Si(100) photoanodes produced photocurrent-onset potentials of \u2212180 \u00b1 20 mV referenced to the equilibrium potential for evolution of O_2(g), photocurrent densities of 29 \u00b1 1.8 mA cm^(\u20132) at the equilibrium potential for evolution of O_2(g), and a solar-to-O_2(g) conversion figure-of-merit of 2.1%.", "date": "2015-02-19", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "6", "number": "4", "publisher": "American Chemical Society", "pagerange": "592-598", "id_number": "CaltechAUTHORS:20150202-095259720", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150202-095259720", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" }, { "agency": "NSF" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation", "grant_number": "GBMF1225" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/jz5026195", "primary_object": { "basename": "jz5026195_si_001.pdf", "url": "https://authors.library.caltech.edu/records/ft6sa-gk325/files/jz5026195_si_001.pdf" }, "pub_year": "2015", "author_list": "Sun, Ke; McDowell, Matthew T.; et el." }, { "id": "https://authors.library.caltech.edu/records/c1jvk-gww44", "eprint_id": 56170, "eprint_status": "archive", "datestamp": "2023-08-22 14:57:37", "lastmod": "2023-10-20 23:44:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Identification of optimal solar fuel electrocatalysts via high throughput in situ optical measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial synthesis; optical properties; catalytic", "note": "\u00a9 2014 Materials Research Society.\n\nReceived 26 July 2014; accepted 25 September 2014.\n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Ryan R.J. Jones for assistance with preparation of graphics.\n\nPublished - _JMR_JMR30_03_S0884291414002969a.pdf
", "abstract": "Many solar fuel generator designs involve illumination of a photoabsorber stack coated with a catalyst for the oxygen evolution reaction (OER). In this design, impinging light must pass through the catalyst layer before reaching the photoabsorber(s), and thus optical transmission is an important function of the OER catalyst layer. Many oxide catalysts, such as those containing elements Ni and Co, form oxide or oxyhydroxide phases in alkaline solution at operational potentials that differ from the phases observed in ambient conditions. To characterize the transparency of such catalysts during OER operation, 1031 unique compositions containing the elements Ni, Co, Ce, La, and Fe were prepared by a high throughput inkjet printing technique. The catalytic current of each composition was recorded at an OER overpotential of 0.33 V with simultaneous measurement of the spectral transmission. By combining the optical and catalytic properties, the combined catalyst efficiency was calculated to identify the optimal catalysts for solar fuel applications within the material library. The measurements required development of a new high throughput instrument with integrated electrochemistry and spectroscopy measurements, which enables various spectroelectrochemistry experiments.", "date": "2015-02-14", "date_type": "published", "publication": "Journal of Materials Research", "volume": "30", "number": "3", "publisher": "Materials Research Society", "pagerange": "442-450", "id_number": "CaltechAUTHORS:20150327-092659678", "issn": "0884-2914", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150327-092659678", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1557/jmr.2014.296", "primary_object": { "basename": "_JMR_JMR30_03_S0884291414002969a.pdf", "url": "https://authors.library.caltech.edu/records/c1jvk-gww44/files/_JMR_JMR30_03_S0884291414002969a.pdf" }, "pub_year": "2015", "author_list": "Shinde, Aniketa; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/gcgwv-kxb25", "eprint_id": 56304, "eprint_status": "archive", "datestamp": "2023-08-20 04:58:42", "lastmod": "2023-10-23 15:17:57", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" } ] }, "title": "The charge-asymmetric nonlocally determined local-electric (CANDLE) solvation model", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 AIP Publishing LLC.\n\nReceived 10 October 2014; accepted 27 January 2015; published online 11 February 2015.\n\nWe thank Yan-Choi Lam, Dr. Robert Nielsen, and Dr. Yuan Ping for suggesting benchmark systems, for help locating experimental data, and for useful discussions. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.\n\nPublished - 1.4907731.pdf
Submitted - 1410.2922v1.pdf
", "abstract": "Many important applications of electronic structure methods involve molecules or solid surfaces in a solvent medium. Since explicit treatment of the solvent in such methods is usually not practical, calculations often employ continuum solvation models to approximate the effect of the solvent. Previous solvation models either involve a parametrization based on atomic radii, which limits the class of applicable solutes, or based on solute electron density, which is more general but less accurate, especially for charged systems. We develop an accurate and general solvation model that includes a cavity that is a nonlocal functional of both solute electron density and potential, local dielectric response on this nonlocally determined cavity, and nonlocal approximations to the cavity-formation and dispersion energies. The dependence of the cavity on the solute potential enables an explicit treatment of the solvent charge asymmetry. With four parameters per solvent, this \"CANDLE\" model simultaneously reproduces solvation energies of large datasets of neutral molecules, cations, and anions with a mean absolute error of 1.8 kcal/mol in water and 3.0 kcal/mol in acetonitrile.", "date": "2015-02-14", "date_type": "published", "publication": "Journal of Chemical Physics", "volume": "142", "number": "6", "publisher": "American Institute of Physics", "pagerange": "Art. No. 064107", "id_number": "CaltechAUTHORS:20150402-091624373", "issn": "0021-9606", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150402-091624373", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "other_numbering_system": { "items": [ { "id": "1108", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4907731", "primary_object": { "basename": "1.4907731.pdf", "url": "https://authors.library.caltech.edu/records/gcgwv-kxb25/files/1.4907731.pdf" }, "related_objects": [ { "basename": "1410.2922v1.pdf", "url": "https://authors.library.caltech.edu/records/gcgwv-kxb25/files/1410.2922v1.pdf" } ], "pub_year": "2015", "author_list": "Sundararaman, Ravishankar and Goddard, William A., III" }, { "id": "https://authors.library.caltech.edu/records/xdf2h-1wk64", "eprint_id": 54057, "eprint_status": "archive", "datestamp": "2023-08-20 04:44:08", "lastmod": "2023-10-19 23:35:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Shinde-A", "name": { "family": "Shinde", "given": "Aniketa" }, "orcid": "0000-0003-2386-3848" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Parallel Electrochemical Treatment System and Application for Identifying Acid-Stable Oxygen Evolution Electrocatalysts", "ispublished": "pub", "full_text_status": "restricted", "keywords": "solar fuels, high throughput, oxygen evolution, electrochemical stability, combinatorial electrochemistry", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: September 26, 2014; Revised: December 1, 2014; Publication Date (Web): January 5, 2015. \n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993).", "abstract": "Many energy technologies require electrochemical stability or preactivation of functional materials. Due to the long experiment duration required for either electrochemical preactivation or evaluation of operational stability, parallel screening is required to enable high throughput experimentation. Imposing operational electrochemical conditions to a library of materials in parallel creates several opportunities for experimental artifacts. We discuss the electrochemical engineering principles and operational parameters that mitigate artifacts in the parallel electrochemical treatment system. We also demonstrate the effects of resistive losses within the planar working electrode through a combination of finite element modeling and illustrative experiments. Operation of the parallel-plate, membrane-separated electrochemical treatment system is demonstrated by exposing a composition library of mixed-metal oxides to oxygen evolution conditions in 1 M sulfuric acid for 2 h. This application is particularly important because the electrolysis and photoelectrolysis of water are promising future energy technologies inhibited by the lack of highly active, acid-stable catalysts containing only earth abundant elements.", "date": "2015-02", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "17", "number": "2", "publisher": "American Chemical Society", "pagerange": "71-75", "id_number": "CaltechAUTHORS:20150126-085330620", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150126-085330620", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/co500148p", "pub_year": "2015", "author_list": "Jones, Ryan J. R.; Shinde, Aniketa; et el." }, { "id": "https://authors.library.caltech.edu/records/dn169-9z703", "eprint_id": 53859, "eprint_status": "archive", "datestamp": "2023-08-22 14:48:53", "lastmod": "2023-10-19 22:18:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pesenson-M-Z", "name": { "family": "Pesenson", "given": "Misha Z." } }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Statistical Analysis and Interpolation of Compositional Data in Materials Science", "ispublished": "pub", "full_text_status": "restricted", "keywords": "high-throughput screening; electrocatalyst; inkjet printing; sputtering; thin-films; interpolation; compositional data; big data; complex data; statistical data analysis", "note": "\u00a9 2014 American Chemical Society.\n\nReceived: September 17, 2014; revised: November 26, 2014. Publication Date (Web): December 29, 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC000499.", "abstract": "Compositional data are ubiquitous in chemistry and materials science: analysis of elements in multicomponent systems, combinatorial problems, etc., lead to data that are non-negative and sum to a constant (for example, atomic concentrations). The constant sum constraint restricts the sampling space to a simplex instead of the usual Euclidean space. Since statistical measures such as mean and standard deviation are defined for the Euclidean space, traditional correlation studies, multivariate analysis, and hypothesis testing may lead to erroneous dependencies and incorrect inferences when applied to compositional data. Furthermore, composition measurements that are used for data analytics may not include all of the elements contained in the material; that is, the measurements may be subcompositions of a higher-dimensional parent composition. Physically meaningful statistical analysis must yield results that are invariant under the number of composition elements, requiring the application of specialized statistical tools. We present specifics and subtleties of compositional data processing through discussion of illustrative examples. We introduce basic concepts, terminology, and methods required for the analysis of compositional data and utilize them for the spatial interpolation of composition in a sputtered thin film. The results demonstrate the importance of this mathematical framework for compositional data analysis (CDA) in the fields of materials science and chemistry.", "date": "2015-02", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "17", "number": "2", "publisher": "American Chemical Society", "pagerange": "130-136", "id_number": "CaltechAUTHORS:20150120-090320534", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150120-090320534", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC000499" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/co5001458", "pub_year": "2015", "author_list": "Pesenson, Misha Z.; Suram, Santosh K.; et el." }, { "id": "https://authors.library.caltech.edu/records/zx5dk-ap869", "eprint_id": 55671, "eprint_status": "archive", "datestamp": "2023-08-22 14:51:02", "lastmod": "2023-10-20 22:57:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Walczak-K-A", "name": { "family": "Walczak", "given": "Karl" } }, { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Karp-C-L", "name": { "family": "Karp", "given": "Christoph" } }, { "id": "Beeman-J-W", "name": { "family": "Beeman", "given": "Jeffrey W." } }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew" }, "orcid": "0000-0003-4682-9757" }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Sharp-I-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Amashukeli-X", "name": { "family": "Amashukeli", "given": "Xenia" } }, { "id": "West-W-C", "name": { "family": "West", "given": "William" } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "Modeling, Simulation, and Fabrication of a Fully Integrated, Acid-stable, Scalable Solar-Driven Water-Splitting System", "ispublished": "pub", "full_text_status": "public", "keywords": "multi-physics modeling; prototype; solar fuels; tungsten oxide; water splitting", "note": "\u00a9 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: August 26, 2014; Published online on January 7, 2015.\n\nThis material is based upon work performed by the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nSupplemental Material - cssc_201402896_sm_miscellaneous_information.pdf
", "abstract": "A fully integrated solar-driven water-splitting system comprised of WO3/FTO/p^(+)n Si as the photoanode, Pt/TiO_2/Ti/n^(+)p Si as the photocathode, and Nafion as the membrane separator, was simulated, assembled, operated in 1.0\u2009M HClO_4, and evaluated for performance and safety characteristics under dual side illumination. A multi-physics model that accounted for the performance of the photoabsorbers and electrocatalysts, ion transport in the solution electrolyte, and gaseous product crossover was first used to define the optimal geometric design space for the system. The photoelectrodes and the membrane separators were then interconnected in a louvered design system configuration, for which the light-absorbing area and the solution-transport pathways were simultaneously optimized. The performance of the photocathode and the photoanode were separately evaluated in a traditional three-electrode photoelectrochemical cell configuration. The photocathode and photoanode were then assembled back-to-back in a tandem configuration to provide sufficient photovoltage to sustain solar-driven unassisted water-splitting. The current\u2013voltage characteristics of the photoelectrodes showed that the low photocurrent density of the photoanode limited the overall solar-to-hydrogen (STH) conversion efficiency due to the large band gap of WO_3. A hydrogen-production rate of 0.17\u2005mL\u2009hr^\u22121 and a STH conversion efficiency of 0.24\u2009% was observed in a full cell configuration for >20\u2005h with minimal product crossover in the fully operational, intrinsically safe, solar-driven water-splitting system. The solar-to-hydrogen conversion efficiency, \u03b7S_TH, calculated using the multiphysics numerical simulation was in excellent agreement with the experimental behavior of the system. The value of \u03b7STH was entirely limited by the performance of the photoelectrochemical assemblies employed in this study. The louvered design provides a robust platform for implementation of various types of photoelectrochemical assemblies, and can provide an approach to significantly higher solar conversion efficiencies as new and improved materials become available.", "date": "2015-02", "date_type": "published", "publication": "ChemSusChem", "volume": "8", "number": "3", "publisher": "Wiley", "pagerange": "544-551", "id_number": "CaltechAUTHORS:20150310-113150374", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150310-113150374", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201402896", "primary_object": { "basename": "cssc_201402896_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/zx5dk-ap869/files/cssc_201402896_sm_miscellaneous_information.pdf" }, "pub_year": "2015", "author_list": "Walczak, Karl; Chen, Yikai; et el." }, { "id": "https://authors.library.caltech.edu/records/3j3em-rcz45", "eprint_id": 56006, "eprint_status": "archive", "datestamp": "2023-08-22 14:51:26", "lastmod": "2023-10-20 23:32:16", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Berweger-S", "name": { "family": "Berweger", "given": "Samuel" } }, { "id": "Weber-J-C", "name": { "family": "Weber", "given": "Joel C." } }, { "id": "John-Jimmy", "name": { "family": "John", "given": "Jimmy" }, "orcid": "0000-0002-8772-8939" }, { "id": "Velazquez-J-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Pieterick-A-P", "name": { "family": "Pieterick", "given": "Adam" } }, { "id": "Sanford-N-A", "name": { "family": "Sanford", "given": "Norman A." } }, { "id": "Davydov-A-V", "name": { "family": "Davydov", "given": "Albert V." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce" }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Wallis-T-M", "name": { "family": "Wallis", "given": "Thomas M." } }, { "id": "Kabos-P", "name": { "family": "Kabos", "given": "Pavel" } } ] }, "title": "Microwave Near-Field Imaging of Two-Dimensional Semiconductors", "ispublished": "pub", "full_text_status": "public", "keywords": "Transition metal dichalcogenide; MoS_2; microwave; near-field; quantum capacitance; atomic force microscope", "note": "\u00a9 2015 American Chemical Society.\n\nReceived: October 24, 2014; Revised: January 20, 2015; Published: January 27, 2015.\n\nWe would like to thank Will Gannett, Mark Keller, and Alexandra Curtin for helpful advice on sample preparation. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. Mention of commercial products is for informational purposes only, it does not imply NIST's recommendation or endorsement.\n\nSupplemental Material - nl504960u_si_001.pdf
", "abstract": "Optimizing new generations of two-dimensional devices based on van der Waals materials will require techniques capable of measuring variations in electronic properties in situ and with nanometer spatial resolution. We perform scanning microwave microscopy (SMM) imaging of single layers of MoS_2 and n- and p-doped WSe_2. By controlling the sample charge carrier concentration through the applied tip bias, we are able to reversibly control and optimize the SMM contrast to image variations in electronic structure and the localized effects of surface contaminants. By further performing tip bias-dependent point spectroscopy together with finite element simulations, we distinguish the effects of the quantum capacitance and determine the local dominant charge carrier species and dopant concentration. These results underscore the capability of SMM for the study of 2D materials to image, identify, and study electronic defects.", "date": "2015-02", "date_type": "published", "publication": "Nano Letters", "volume": "15", "number": "2", "publisher": "American Chemical Society", "pagerange": "1122-1127", "id_number": "CaltechAUTHORS:20150324-085931498", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150324-085931498", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/nl504960u", "primary_object": { "basename": "nl504960u_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3j3em-rcz45/files/nl504960u_si_001.pdf" }, "pub_year": "2015", "author_list": "Berweger, Samuel; Weber, Joel C.; et el." }, { "id": "https://authors.library.caltech.edu/records/xfdtx-mxp88", "eprint_id": 57342, "eprint_status": "archive", "datestamp": "2023-08-20 04:38:53", "lastmod": "2023-10-23 17:17:49", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Grzanna-J", "name": { "family": "Grzanna", "given": "J." } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H. J." }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Oscillations at the Si/electrolyte contact: Relation to Quantum Mechanics", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 The Authors. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.\n\nPublished - 1742-6596_574_1_012024.pdf
", "abstract": "The basic process at the surface of the Si electrode is characterized by a cyclic oxidation of a thin silicon layer and the subsequent removal of the oxide by etching. Here, the oxide thickness evolves not uniformly due to cracks and nanopores. The mathematical model used to describe the phenomenon is based on a sequence of time dependent (oxide thickness) oscillator density functions that describes the passing of the (infinitesimal) oscillators through their minimum at each cycle. Two consecutive oscillator density functions are connected by a second order linear integral equation representing a Markov process. The kernel of the integral equation is a normalized Greens Function and represents the probability distribution for the periods of the oscillators during a cycle. Both, the oscillator density function and the two-dimensional probability density for the periods of the oscillators, define a random walk. A relation between the oscillator density functions and solutions of the Fokker-Planck equation can be constructed. This allows a connection of the oscillations, originally considered only for the description of a photo-electrochemical observation, to the Schrodinger equation. In addition, if the trajectory of a virtual particle, located at the silicon oxide electrode surface, is considered during one oscillatory cycle, then it can be shown that the displacement of the particle measured at the electrode surface performs a Brownian motion.", "date": "2015-01-21", "date_type": "published", "publication": "Journal of Physics: Conference Series", "volume": "574", "number": "1", "publisher": "IOP", "pagerange": "Art. No. 012024", "id_number": "CaltechAUTHORS:20150507-135543426", "issn": "1742-6596", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150507-135543426", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1088/1742-6596/574/1/012024", "primary_object": { "basename": "1742-6596_574_1_012024.pdf", "url": "https://authors.library.caltech.edu/records/xfdtx-mxp88/files/1742-6596_574_1_012024.pdf" }, "pub_year": "2015", "author_list": "Grzanna, J. and Lewerenz, H. J." }, { "id": "https://authors.library.caltech.edu/records/rc4xp-yqj60", "eprint_id": 51816, "eprint_status": "archive", "datestamp": "2023-08-20 04:29:37", "lastmod": "2023-10-18 17:57:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-Matthew-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Sun-Ke", "name": { "family": "Sun", "given": "Ke" }, "orcid": "0000-0001-8209-364X" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stabilization of Si microwire arrays for solar-driven H\u2082O oxidation to O\u2082(g) in 1.0 M KOH(aq) using conformal coatings of amorphous TiO\u2082", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 22 Sep 2014, Accepted 29 Oct 2014,\nFirst published online 05 Nov 2014.\n\nThe authors would like to acknowledge Dr Ragip Pala for assistance with the spectral response measurement system. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. M. R. S. is supported by a graduate fellowship from the Resnick Institute for Sustainability. The authors also acknowledge support from the Gordon and Betty Moore Foundation.\n\nPublished - c4ee03012e.pdf
Supplemental Material - c4ee03012e1.pdf
", "abstract": "Conductive, amorphous TiO\u2082 coatings deposited by atomic-layer deposition, in combination with a sputter deposited NiCrO\u2093 oxygen-evolution catalyst, have been used to protect Si microwire arrays from passivation or corrosion in contact with aqueous electrolytes. Coated np\u207a-Si/TiO\u2082/NiCrO\u2093 as well as heterojunction n-Si/TiO\u2082/NiCrO\u2093 Si microwire-array photoanodes exhibited stable photoelectrochemical operation in aqueous ferri-/ferro-cyanide solutions. The coatings also allowed for photoanodic water oxidation in 1.0 M KOH(aq) solutions for >2200 h of continuous operation under simulated 1 Sun conditions with 100% Faradaic efficiency for the evolution of O\u2082(g).", "date": "2015-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "203-207", "id_number": "CaltechAUTHORS:20141117-083607403", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141117-083607403", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c4ee03012e", "primary_object": { "basename": "c4ee03012e.pdf", "url": "https://authors.library.caltech.edu/records/rc4xp-yqj60/files/c4ee03012e.pdf" }, "related_objects": [ { "basename": "c4ee03012e1.pdf", "url": "https://authors.library.caltech.edu/records/rc4xp-yqj60/files/c4ee03012e1.pdf" } ], "pub_year": "2015", "author_list": "Shaner, Matthew R.; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/c63sw-pdv64", "eprint_id": 50252, "eprint_status": "archive", "datestamp": "2023-08-20 04:29:31", "lastmod": "2023-10-17 22:52:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Nielander-A-C", "name": { "family": "Nielander", "given": "Adam C." }, "orcid": "0000-0002-3639-2427" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Papadantonakis-Kimberly-M", "name": { "family": "Papadantonakis", "given": "Kimberly M." }, "orcid": "0000-0002-9900-5500" }, { "id": "Francis-S-A", "name": { "family": "Francis", "given": "Sonja A." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "A taxonomy for solar fuels generators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 18 Jul 2014, Accepted 19 Sep 2014,\nFirst published online 19 Sep 2014.\n\nACN acknowledges the NSF, Grant CHE-1214152, and the National Science Foundation Graduate Research Fellowship for support. KMP acknowledges support from the DOE, Grant DEFG02-03ER15483. MRS acknowledges the Resnick Sustainability\nInstitute for a graduate fellowship. This material is based upon\nwork performed by the Joint Center for Artificial Photosynthesis,\na DOE Energy Innovation Hub, supported through the\nOffice of Science of the U.S. Department of Energy under Award\nNumber DE-SC0004993.\n\nPublished - c4ee02251c.pdf
", "abstract": "A number of approaches to solar fuels generation are being developed, each of which has associated\nadvantages and challenges. Many of these solar fuels generators are identified as \"photoelectrochemical\ncells\" even though these systems collectively operate based on a suite of fundamentally different\nphysical principles. To facilitate appropriate comparisons between solar fuels generators, as well as to\nenable concise and consistent identification of the state-of-the-art for designs based on comparable\noperating principles, we have developed a taxonomy and nomenclature for solar fuels generators based\non the source of the asymmetry that separates photogenerated electrons and holes. Three basic device\ntypes have been identified: photovoltaic cells, photoelectrochemical cells, and particulate/molecular\nphotocatalysts. We outline the advantages and technological challenges associated with each type, and\nprovide illustrative examples for each approach as well as for hybrid approaches.", "date": "2015-01-01", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "8", "number": "1", "publisher": "Royal Society of Chemistry", "pagerange": "16-25", "id_number": "CaltechAUTHORS:20141008-080542214", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141008-080542214", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1214152" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/c4ee02251c", "primary_object": { "basename": "c4ee02251c.pdf", "url": "https://authors.library.caltech.edu/records/c63sw-pdv64/files/c4ee02251c.pdf" }, "pub_year": "2015", "author_list": "Nielander, Adam C.; Shaner, Matthew R.; et el." }, { "id": "https://authors.library.caltech.edu/records/54681-w7x47", "eprint_id": 55039, "eprint_status": "archive", "datestamp": "2023-08-20 04:22:56", "lastmod": "2023-10-20 21:16:25", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Yang-Xiaogang", "name": { "family": "Yang", "given": "Xiaogang" }, "orcid": "0000-0002-1142-3100" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "He-Yumin", "name": { "family": "He", "given": "Yumin" } }, { "id": "Thorne-J", "name": { "family": "Thorne", "given": "James" } }, { "id": "Zheng-Zhi", "name": { "family": "Zheng", "given": "Zhi" }, "orcid": "0000-0002-5889-4305" }, { "id": "Wang-Dunwei", "name": { "family": "Wang", "given": "Dunwei" } } ] }, "title": "Enabling practical electrocatalyst-assisted photoelectrochemical water splitting with earth abundant materials", "ispublished": "pub", "full_text_status": "restricted", "keywords": "photoelectrochemical\nwater splitting,\nefficiency,\nstability,\ninterface,\nearth abundance", "note": "\u00a9 2014 Tsinghua University Press. and Springer-Verlag Berlin\nHeidelberg. Received: 7 August 2014. Revised: 23 October 2014. Accepted: 13 November 2014. Date: 27 Dec 2014.\n\nThis work was supported by Boston College, NSF (DMR 1055762 and 1317280), and MassCEC. R. L. is supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We acknowledge partial support by the Program for Innovative Research Team (in Science and Technology) in University of Henan Province (No. 2012IRTSTHN021), Innovation Scientists and Technicians Troop Construction Projects of Henan Province (No. 144200510014) and National Natural Science Foundation of China (No. 21273192). D.W. is an Alfred P. Sloan Fellow.", "abstract": "Sustainable development and continued prosperity of humanity hinge on the availability of renewable energy sources on a terawatts scale. In the long run, solar energy is the only source that can meet this daunting demand. Widespread utilization of solar energy faces challenges as a result of its diffusive (hence low energy density) and intermittent nature. How to effectively harvest, concentrate, store and redistribute solar energy constitutes a fundamental challenge that the scientific community needs to address. Photoelectrochemical (PEC) water splitting is a process that can directly convert solar energy into chemical energy and store it in chemical bonds, by producing hydrogen as a clean fuel source. It has received significant research attention lately. Here we provide a concise review of the key issues encountered in carrying out PEC water splitting. Our focus is on the balance of considerations such as stability, earth abundance, and efficiency. Particular attention is paid to the combination of photoelectrodes with electrocatalysts, especially on the interfaces between different components.", "date": "2015-01", "date_type": "published", "publication": "Nano Research", "volume": "8", "number": "1", "publisher": "Springer Verlag", "pagerange": "56-81", "id_number": "CaltechAUTHORS:20150220-072846889", "issn": "1998-0124", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150220-072846889", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Boston College" }, { "agency": "NSF", "grant_number": "DMR 1055762" }, { "agency": "NSF", "grant_number": "1317280" }, { "agency": "Joint Center for Artificial Photosynthesis" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of Henan Province Program for Innovative Research Team", "grant_number": "2012IRTSTHN021" }, { "agency": "Henan Province Technicians Troop Construction Projects", "grant_number": "144200510014" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21273192" }, { "agency": "Alfred P. Sloan Foundation" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12274-014-0645-2", "pub_year": "2015", "author_list": "Yang, Xiaogang; Liu, Rui; et el." }, { "id": "https://authors.library.caltech.edu/records/vq8z5-yrw51", "eprint_id": 53853, "eprint_status": "archive", "datestamp": "2023-08-20 04:20:15", "lastmod": "2023-10-19 22:17:55", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Cornell-E-W", "name": { "family": "Cornell", "given": "Earl W." } }, { "id": "Marcin-M-R", "name": { "family": "Marcin", "given": "Martin R." } }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "Ryan J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "Paul F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High-throughput on-the-fly scanning ultraviolet-visible dual-sphere spectrometer", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2015 AIP Publishing.\n\nReceived 10 October 2014; accepted 21 December 2014; published online 13 January 2015.\n\nThis manuscript is based upon work performed by the\nJoint Center for Artificial Photosynthesis, a DOE Energy\nInnovation Hub, supported through the Office of Science of\nthe U.S. Department of Energy (Award No. DE-SC0004993).\n\nPublished - 1.4905365.pdf
", "abstract": "We have developed an on-the-fly scanning spectrometer operating in the UV-visible and near-infrared that can simultaneously perform transmission and total reflectance measurements at the rate better than 1 sample per second. High throughput optical characterization is important for screening functional materials for a variety of new applications. We demonstrate the utility of the instrument for screening new light absorber materials by measuring the spectral absorbance, which is subsequently used for deriving band gap information through Tauc plot analysis.", "date": "2015-01", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "86", "number": "1", "publisher": "American Institute of Physics", "pagerange": "Art. No. 013904", "id_number": "CaltechAUTHORS:20150120-081217429", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150120-081217429", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4905365", "primary_object": { "basename": "1.4905365.pdf", "url": "https://authors.library.caltech.edu/records/vq8z5-yrw51/files/1.4905365.pdf" }, "pub_year": "2015", "author_list": "Mitrovic, Slobodan; Cornell, Earl W.; et el." }, { "id": "https://authors.library.caltech.edu/records/5dqs1-2a635", "eprint_id": 49770, "eprint_status": "archive", "datestamp": "2023-08-22 14:35:08", "lastmod": "2023-10-17 22:11:01", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Sun-Guofeng", "name": { "family": "Sun", "given": "Guofeng" } }, { "id": "McCrory-Charles-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "McKone-James-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Ferrer-Ivonne-M", "name": { "family": "Ferrer", "given": "Ivonne M." } }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Chmielowiec-Brian", "name": { "family": "Chmielowiec", "given": "Brian" }, "orcid": "0000-0002-3004-9345" }, { "id": "Lacy-David-C", "name": { "family": "Lacy", "given": "David C." } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Sanabria-Chinchilla-Jean", "name": { "family": "Sanabria-Chinchilla", "given": "Jean" } }, { "id": "Amashukeli-Xenia", "name": { "family": "Amashukeli", "given": "Xenia" } }, { "id": "Royea-William-J", "name": { "family": "Royea", "given": "William J." } }, { "id": "Brunschwig-Bruce-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Stickney-John-L", "name": { "family": "Stickney", "given": "John L." } } ] }, "title": "Electrochemical surface science twenty years later: Expeditions into the electrocatalysis of reactions at the core of artificial photosynthesis", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Electroctrochemical surface science; Artificial photosynthesis; Water-splitting reaction; Carbon dioxide reduction reaction; Electrochemistry-surface science apparatus", "note": "\u00a9 2014 Elsevier B.V.\n\nAvailable online 22 July 2014.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. JRM was the recipient of a US DOE graduate research fellowship. BSB would like to acknowledge Beckman Institute of the California Institute of Technology for support. MPS and JLS thank Arthur T. Hubbard; friend, colleague and mentor.", "abstract": "Surface science research fixated on phenomena and processes that transpire at the electrode-electrolyte interface has been pursued in the past. A considerable proportion of the earlier work was on materials and reactions pertinent to the operation of small-molecule fuel cells. The experimental approach integrated a handful of surface-sensitive physical\u2013analytical methods with traditional electrochemical techniques, all harbored in a single environment-controlled electrochemistry-surface science apparatus (EC-SSA); the catalyst samples were typically precious noble metals constituted of well-defined single-crystal surfaces. More recently, attention has been diverted from fuel-to-energy generation to its converse, (solar) energy-to-fuel transformation; e.g., instead of water synthesis (from hydrogen and oxygen) in fuel cells, water decomposition (to hydrogen and oxygen) in artificial photosynthesis. The rigorous surface-science protocols remain unchanged but the experimental capabilities have been expanded by the addition of several characterization techniques, either as EC-SSA components or as stand-alone instruments. The present manuscript describes results selected from on-going studies of earth-abundant electrocatalysts for the reactions that underpin artificial photosynthesis: nickel-molybdenum alloys for the hydrogen evolution reaction, calcium birnessite as a heterogeneous analogue for the oxygen-evolving complex in natural photosynthesis, and single-crystalline copper in relation to the carbon dioxide reduction reaction.", "date": "2015-01", "date_type": "published", "publication": "Surface Science", "volume": "631", "publisher": "Elsevier", "pagerange": "285-294", "id_number": "CaltechAUTHORS:20140917-091954518", "issn": "0039-6028", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140917-091954518", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.susc.2014.06.028", "pub_year": "2015", "author_list": "Soriaga, Manuel P.; Baricuatro, Jack H.; et el." }, { "id": "https://authors.library.caltech.edu/records/89sdz-zb609", "eprint_id": 52805, "eprint_status": "archive", "datestamp": "2023-08-20 04:06:43", "lastmod": "2023-10-18 21:36:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack Hess" } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John Mathew" }, "orcid": "0000-0002-2863-5265" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "The Evolution of the Polycrystalline Copper Surface, First to Cu(111) and Then to Cu(100), at a Fixed CO_2RR Potential: A Study by Operando EC-STM", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: November 12, 2014; Revised: December 4, 2014. Publication Date (Web): December 9, 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993.", "abstract": "A study based on operando electrochemical scanning tunneling microscopy (EC-STM) has shown that a polycrystalline Cu electrode held at a fixed negative potential, \u22120.9 V (vs SHE), in the vicinity of CO_2 reduction reactions (CO2RR) in 0.1 M KOH, undergoes stepwise surface reconstruction, first to Cu(111) within 30 min, and then to Cu(100) after another 30 min; no further surface transformations occurred after establishment of the Cu(100) surface. The results may help explain the Cu(100)-like behavior of Cu(pc) in terms of CO_2RR product selectivity. They likewise suggest that products exclusive to Cu(100) single-crystal electrodes may be generated through the use of readily available inexpensive polycrystalline Cu electrodes. The study highlights the dynamic nature of heterogeneous electrocatalyst surfaces and also underscores the importance of operando interrogations when structure\u2013composition\u2013reactivity correlations are intended.", "date": "2014-12-23", "date_type": "published", "publication": "Langmuir", "volume": "30", "number": "50", "publisher": "American Chemical Society", "pagerange": "15053-15056", "id_number": "CaltechAUTHORS:20141215-100027935", "issn": "0743-7463", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141215-100027935", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/la504445g", "pub_year": "2014", "author_list": "Kim, Youn-Geun; Baricuatro, Jack Hess; et el." }, { "id": "https://authors.library.caltech.edu/records/re8ys-5y746", "eprint_id": 50531, "eprint_status": "archive", "datestamp": "2023-08-20 04:03:35", "lastmod": "2023-10-17 23:54:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Verlage-Erik", "name": { "family": "Verlage", "given": "Erik" } }, { "id": "Hemminger-John-C", "name": { "family": "Hemminger", "given": "John C." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "CoP as an Acid-Stable Active Electrocatalyst for the Hydrogen-Evolution Reaction: Electrochemical Synthesis, Interfacial Characterization and Performance Evaluation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: June 2, 2014. Revised: September 27, 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. A.I.C. acknowledges a National Science Foundation Graduate Research Fellowship for support.\n\nSupplemental Material - jp5054452_si_001.pdf
", "abstract": "Films of CoP have been electrochemically synthesized, characterized, and evaluated for performance as a catalyst for the hydrogen-evolution reaction (HER). The film was synthesized by cathodic deposition from a boric acid solution of Co^(2+) and H_2PO_2^\u2013 on copper substrates followed by operando remediation of exogenous contaminants. The films were characterized structurally and compositionally by scanning-electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and Raman spectrophotometry. The catalytic activity was evaluated by cyclic voltammetry and chronopotentiometry. Surface characterization prior to electrocatalysis indicated that the film consisted of micrometer-sized spherical clusters located randomly and loosely on a slightly roughened surface. The composition of both the clusters and surface consisted of cobalt in the metallic, phosphide, and amorphous-oxide forms (CoO\u00b7Co_2O_3) and of phosphorus as phosphide and orthophosphate. The orthophosphate species, produced by air-oxidation, were eliminated upon HER electrocatalysis in sulfuric acid. The operando film purification yielded a functional electrocatalyst with a Co:P stoichiometric ratio of 1:1. After the HER, the surface was densely packed with micrometer-sized, mesa-like particles whose tops were flat and smooth. The CoP eletrodeposit exhibited an 85 mV overvoltage (\u03b7) for the HER at a current density of 10 mA cm^(\u20132) and was stable under operation in highly acidic solution, with an increase in \u03b7 of 18 mV after 24 h of continuous operation. The comparative HER catalytic performance of CoP, film or nanoparticles, is as follows: \u03b7_(Pt) < \u03b7_(CoP film) = \u03b7_(CoP NP), \u03b7_(Ni_2P) < \u03b7_(CoSe)_2 < \u03b7_(MoS)_2 < \u03b7_(MoSe)_2.", "date": "2014-12-18", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "50", "publisher": "American Chemical Society", "pagerange": "29294-29300", "id_number": "CaltechAUTHORS:20141020-091512216", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141020-091512216", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp5054452", "primary_object": { "basename": "jp5054452_si_001.pdf", "url": "https://authors.library.caltech.edu/records/re8ys-5y746/files/jp5054452_si_001.pdf" }, "pub_year": "2014", "author_list": "Saadi, Fadl H.; Carim, Azhar I.; et el." }, { "id": "https://authors.library.caltech.edu/records/aqd0d-syb19", "eprint_id": 53056, "eprint_status": "archive", "datestamp": "2023-08-20 04:02:44", "lastmod": "2023-10-18 21:54:51", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sundararaman-R", "name": { "family": "Sundararaman", "given": "Ravishankar" }, "orcid": "0000-0002-0625-4592" }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Jermyn-A-S", "name": { "family": "Jermyn", "given": "Adam S." }, "orcid": "0000-0001-5048-9973" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Theoretical predictions for hot-carrier generation from surface plasmon decay", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Macmillan Publishers Limited. This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article's Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ \n\nReceived 03 September 2014. Accepted 07 November 2014. Published 16 December 2014. \n\nWe thank Marco Bernardi for detailed feedback on and suggestions towards improving this manuscript; Tonatiuh Rangel, Jamal Mustafa and Marco Bernardi for private communications of noble metal GW band structures; and Yuan Ping for useful discussions. This material is based on the work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. P.N. is supported by a National Science Foundation Graduate Research Fellowship and by the Resnick Sustainability Institute.\n\nPublished - ncomms6788.pdf
", "abstract": "Decay of surface plasmons to hot carriers finds a wide variety of applications in energy conversion, photocatalysis and photodetection. However, a detailed theoretical description of plasmonic hot-carrier generation in real materials has remained incomplete. Here we report predictions for the prompt distributions of excited 'hot' electrons and holes generated by plasmon decay, before inelastic relaxation, using a quantized plasmon model with detailed electronic structure. We find that carrier energy distributions are sensitive to the electronic band structure of the metal: gold and copper produce holes hotter than electrons by 1\u20132\u2009eV, while silver and aluminium distribute energies more equitably between electrons and holes. Momentum-direction distributions for hot carriers are anisotropic, dominated by the plasmon polarization for aluminium and by the crystal orientation for noble metals. We show that in thin metallic films intraband transitions can alter the carrier distributions, producing hotter electrons in gold, but interband transitions remain dominant.", "date": "2014-12-16", "date_type": "published", "publication": "Nature Communications", "volume": "5", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 5788", "id_number": "CaltechAUTHORS:20141219-150047470", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141219-150047470", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "other_numbering_system": { "items": [ { "id": "1099", "name": "WAG" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1038/ncomms6788", "pmcid": "PMC4284641", "primary_object": { "basename": "ncomms6788.pdf", "url": "https://authors.library.caltech.edu/records/aqd0d-syb19/files/ncomms6788.pdf" }, "pub_year": "2014", "author_list": "Sundararaman, Ravishankar; Narang, Prineha; et el." }, { "id": "https://authors.library.caltech.edu/records/fyqm5-tdn05", "eprint_id": 53992, "eprint_status": "archive", "datestamp": "2023-08-20 04:02:22", "lastmod": "2023-10-19 22:28:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaffer-D-W", "name": { "family": "Shaffer", "given": "David W." } }, { "id": "Johnson-S-I", "name": { "family": "Johnson", "given": "Samantha I." } }, { "id": "Rheingold-A-L", "name": { "family": "Rheingold", "given": "Arnold L." }, "orcid": "0000-0003-4472-8127" }, { "id": "Ziller-J-W", "name": { "family": "Ziller", "given": "Joseph W." } }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Nielsen-R-J", "name": { "family": "Nielsen", "given": "Robert J." }, "orcid": "0000-0002-7962-0186" }, { "id": "Yang-Jenny-Y", "name": { "family": "Yang", "given": "Jenny Y." } } ] }, "title": "Reactivity of a Series of Isostructural Cobalt Pincer Complexes with CO_2, CO, and H^+", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: September 8, 2014. Publication Date (Web): December 3, 2014. \n\nThis material is based upon work performed at the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub,\nsupported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993,\nand additional support from the School of Physical Sciences at\nthe University of California, Irvine. S.I.J. would like to\nacknowledge support from the National Science Foundation\nGraduate Research Fellowship under Grant DGE# 1144469.\nThe authors thank C. Tsay and L. Henling for helpful\ndiscussions and assistance.\n\nSupplemental Material - ic5021725_si_001.pdf
Supplemental Material - ic5021725_si_002.cif
Supplemental Material - ic5021725_si_003.cif
Supplemental Material - ic5021725_si_004.cif
Supplemental Material - ic5021725_si_005.cif
Supplemental Material - ic5021725_si_006.cif
", "abstract": "The preparation and characterization of a series of isostructural cobalt complexes Co(t-Bu)_2(P^EPy^EP)(t-Bu)_2(CH_3CN)_2]-[BF_4]_2 (Py = pyridine, E = CH_2, NH, O, and X = BF_4 (1a-c)) and the corresponding one-electron reduced analogues Co(t-Bu)_2P^EPy^EP(t-Bu)_2(CH_3CN)_2][BF_4]_2 (2a-c) are reported. The reactivity of the reduced cobalt complexes with CO_2, CO, and H^+ to generate intermediates in a CO_2 to CO and H_2O reduction cycle are described. The reduction of 1a-c and subsequent reactivity with CO_2 was investigated by cyclic voltammetry, and for 1a also by infrared spectroelectrochemistry. The corresponding CO complexes of (2a-c) were prepared, and the Co-CO bond strengths were characterized by IR spectroscopy. Quantum mechanical methods (B3LYP-d3 with solvation) were used to characterize the competitive reactivity of the reduced cobalt centers with H^+ versus CO_2. By investigating a series of isostructural complexes, correlations in reactivity with ligand electron withdrawing effects are made.", "date": "2014-12-15", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "53", "number": "24", "publisher": "American Chemical Society", "pagerange": "13031-13041", "id_number": "CaltechAUTHORS:20150122-111631531", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150122-111631531", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "University of California, Irvine" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ic5021725", "primary_object": { "basename": "ic5021725_si_006.cif", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_006.cif" }, "related_objects": [ { "basename": "ic5021725_si_001.pdf", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_001.pdf" }, { "basename": "ic5021725_si_002.cif", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_002.cif" }, { "basename": "ic5021725_si_003.cif", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_003.cif" }, { "basename": "ic5021725_si_004.cif", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_004.cif" }, { "basename": "ic5021725_si_005.cif", "url": "https://authors.library.caltech.edu/records/fyqm5-tdn05/files/ic5021725_si_005.cif" } ], "pub_year": "2014", "author_list": "Shaffer, David W.; Johnson, Samantha I.; et el." }, { "id": "https://authors.library.caltech.edu/records/a3sqk-6yh94", "eprint_id": 52221, "eprint_status": "archive", "datestamp": "2023-08-20 04:01:53", "lastmod": "2023-10-18 19:40:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Laga-S-M", "name": { "family": "Laga", "given": "Stephanie M." } }, { "id": "Blakemore-J-D", "name": { "family": "Blakemore", "given": "James D." }, "orcid": "0000-0003-4172-7460" }, { "id": "Henling-L-M", "name": { "family": "Henling", "given": "Lawrence M." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Catalysis of Proton Reduction by a [BO_4]-Bridged Dicobalt Glyoxime", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society.\n\nReceived: July 28, 2014; published: November 19, 2014.\n\nThe authors thank Ivonne Ferrer for helpful discussions and\nAaron Sattler for assistance in preparation of Figure 2. This research was carried out in part at the Molecular Materials Research Center of the Beckman Institute at Caltech. The research was supported by the Resnick Sustainability Institute at Caltech (Postdoctoral Fellowship to J.D.B.) and the NSF CCI Solar Fuels Program (CHE-1305124 and a CCI Postdoctoral Fellowship to J.D.B.). The Bruker KAPPA APEXII X-ray diffractometer was purchased via an NSF CRIF:MU award to the California Institute of Technology (CHE-0639094). Gas chromatographs were collected at the Joint Center for Artificial Photosynthesis at Caltech.\n\nSupplemental Material - ic501804h_si_001.pdf
Supplemental Material - ic501804h_si_002.cif
", "abstract": "We report the preparation of a dicobalt compound with two singly proton-bridged cobaloxime units linked by a central [BO_4] bridge. Reaction of a doubly proton-bridged cobaloxime complex with trimethyl borate afforded the compound in good yield. Single-crystal X-ray diffraction studies confirmed the bridging nature of the [BO_4] moiety. Using electrochemical methods, the dicobalt complex was found to be an electrocatalyst for proton reduction in acetonitrile solution. Notably, the overpotential for proton reduction (954 mV) was found to be higher than in the cases of two analogous single-site cobalt glyoximes under virtually identical conditions.", "date": "2014-12-15", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "53", "number": "24", "publisher": "American Chemical Society", "pagerange": "12668-12670", "id_number": "CaltechAUTHORS:20141201-105741726", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141201-105741726", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF", "grant_number": "CHE-1305124" }, { "agency": "NSF Postdoctoral Fellowship" }, { "agency": "NSF", "grant_number": "CHE-0639094" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "CCI-Solar-Fuels" }, { "id": "JCAP" } ] }, "doi": "10.1021/ic501804h", "primary_object": { "basename": "ic501804h_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a3sqk-6yh94/files/ic501804h_si_001.pdf" }, "related_objects": [ { "basename": "ic501804h_si_002.cif", "url": "https://authors.library.caltech.edu/records/a3sqk-6yh94/files/ic501804h_si_002.cif" } ], "pub_year": "2014", "author_list": "Laga, Stephanie M.; Blakemore, James D.; et el." }, { "id": "https://authors.library.caltech.edu/records/03rh5-j1z05", "eprint_id": 53452, "eprint_status": "archive", "datestamp": "2023-08-20 03:58:01", "lastmod": "2023-10-19 21:45:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Bruce-J-P", "name": { "family": "Bruce", "given": "Jared P." } }, { "id": "Asgari-S", "name": { "family": "Asgari", "given": "Sommayeh" } }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Oliver-D-R", "name": { "family": "Oliver", "given": "Derek R." } }, { "id": "Freund-M-S", "name": { "family": "Freund", "given": "Michael S." }, "orcid": "0000-0003-1104-2292" } ] }, "title": "Measurement of the Electrical Resistance of n-Type Si Microwire/p-Type Conducting Polymer Junctions for Use in Artificial Photosynthesis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: September 11, 2014. Revised: October 29, 2014. Published: October 29, 2014. \n\nFinancial support from the Natural Sciences and Engineering\nResearch Council (NSERC) of Canada, the Canada Foundation\nfor Innovation (CFI), the Manitoba Research and Innovation Fund, and the University of Manitoba is gratefully acknowledged. The work reported made use of surface\ncharacterization infrastructure in the Manitoba Institute for Materials. This work was supported by a National Science\nFoundation (NSF) Center for Chemical Innovation (CCI)\nPowering the Planet (Grants CHE-0802907, CHE-0947829, and NSF-ACCF) and made use of the Molecular Materials Research Center of the Beckman Institute at Caltech and the Kavli Nanoscience Institute at Caltech. This research was undertaken, in part, thanks to funding from the Canada Research Chairs Program. S.A. acknowledges partial support from a U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award, under the EERE Fuel Cell Technologies Program. This material is based in part (support for NSL) upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993.\n\nSupplemental Material - jp509211k_si_001.pdf
", "abstract": "The junction between n-type silicon microwires and p-type conducting polymer PEDOT:PSS (poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate)) was investigated using a soft contact method. Dopant levels within the microwires were varied during growth to give a highly-doped region for improved contact and a low-doped region for light absorption. The low-doped region of the microwires had a dopant density of 5 X 10(17) cm(-3) while the highly-doped region had an increased dopant density of 5 X 10(18) cm(-3) over similar to 20 mu m. Uniform, highly-doped microwires, with a dopant density of 4 X 10(19) cm(3), were used as a comparison. Regions of highly-doped n-type Si microwires (N-D = 5 X 10(18) cm(-3) and 4 X 10(19) cm(-3)) contacted by PEDOT:PSS showed a significantly lower junction resistance compared to the low-doped (3 X 10(17) cm(-3)) regions of the microwire. Junctions incorporating the metal catalyst used during growth were also investigated. Microwires with copper at the interface had similar currentvoltage characteristics to those observed for the highly-doped microwire/conducting polymer junction; however, junctions that incorporated gold exhibited significantly lower resistances, decreasing the iR contribution of the junction by an order of magnitude with respect to the total voltage drop in the entire structure.", "date": "2014-12-04", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "48", "publisher": "American Chemical Society", "pagerange": "27742-27748", "id_number": "CaltechAUTHORS:20150109-083207621", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150109-083207621", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Manitoba Research and Innovation Fund" }, { "agency": "University of Manitoba" }, { "agency": "NSF", "grant_number": "CHE-0802907" }, { "agency": "NSF", "grant_number": "CHE-0947829" }, { "agency": "Canada Research Chairs Program" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/jp509211k", "primary_object": { "basename": "jp509211k_si_001.pdf", "url": "https://authors.library.caltech.edu/records/03rh5-j1z05/files/jp509211k_si_001.pdf" }, "pub_year": "2014", "author_list": "Bruce, Jared P.; Asgari, Sommayeh; et el." }, { "id": "https://authors.library.caltech.edu/records/an8yc-yce17", "eprint_id": 53328, "eprint_status": "archive", "datestamp": "2023-08-20 03:57:37", "lastmod": "2023-10-19 14:46:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans J." }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Semiconductor Surface Transformations for Photoelectrochemical Energy Conversion", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Electrochemical Society.\n\nManuscript submitted October 6, 2014; revised manuscript received November 10, 2014. Published December 3, 2014. \n\nThis paper is part of the JES Focus Issue in Recognition of Adam Heller and His Enduring Contributions to Electrochemistry. \n\nThe author is indebted to the Bell Laboratories team led by Adam Heller, which also included Barry Miller, Klaus Bachmann, Shalini Menezes, Ferdinand Thiel and Dave Aspnes; from the group at the Hahn-Meitner Institute in Berlin (now the Helmholtz Zentrum Berlin after merging with the synchrotron facility Bessy II), I acknowledge contributions of Mohammed Aggour, Juergen Grzanna, Thomas Stempel, Andres Munoz, Katarzyna Skorupska Christian Heine, Thomas Hannappel, Matthias May, Oliver Supplie and Ulrike Bloeck. At Caltech, enlightening discussions with Matthew Shaner, Katherine Fountaine and Harry Atwater are gratefully acknowledged. Part of the work described here was funded by the DFG (Project No. LE 1192\u20134). This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: the composition and the writing of the review as well as\nthe modeling results were supported through the Office of Science of the US Department of Energy under Award No. DE-SC00049993.\n\nPublished - J._Electrochem._Soc.-2014-Lewerenz-H3117-29.pdf
", "abstract": "The issue of photoelectrode stability, while simultaneously maintaining efficient operation in aqueous solutions, is addressed for energy converting half cells and complete photoelectrocatalytic structures. The historical development of stability concepts, their realization and recent advances are described. Examples are presented that span the time from the inception of photoelectrochemical energy conversion to present day's renewed interest in storable solar energy. The application of (photo)corrosion processes for in-situ synthesis of protective coatings is described and chemical and electronic analyses of the interphases formed are given. Future development and innovation routes will be discussed.", "date": "2014-12-03", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "161", "number": "13", "publisher": "Electrochemical Society", "pagerange": "H3117-H3129", "id_number": "CaltechAUTHORS:20150108-085815861", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20150108-085815861", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LE 1192-4" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC00049993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.0211413jes", "primary_object": { "basename": "J._Electrochem._Soc.-2014-Lewerenz-H3117-29.pdf", "url": "https://authors.library.caltech.edu/records/an8yc-yce17/files/J._Electrochem._Soc.-2014-Lewerenz-H3117-29.pdf" }, "pub_year": "2014", "author_list": "Lewerenz, Hans J." }, { "id": "https://authors.library.caltech.edu/records/bwfxg-fe555", "eprint_id": 50142, "eprint_status": "archive", "datestamp": "2023-08-22 14:13:00", "lastmod": "2023-10-17 22:32:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Cathodic regeneration of a clean and ordered Cu(100)-(1\u00d71) surface from an air-oxidized and disordered electrode: An operando STM study", "ispublished": "pub", "full_text_status": "public", "keywords": "Operando electrochemical scanning tunneling microscopy; Copper electrocataysts for co2 reduction; Cathodic regeneration of ordered Cu(hkl) from oxided surfaces; Air-oxidized copper electrocatalyst surfaces; In Situ electrochemical scanning tunneling microscopy", "note": "\u00a9 2014 Elsevier B.V. \n\nReceived 2 August 2014, Accepted 9 September 2014, Available online 19 September 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nThere is no conflict of interest among the authors.\n\nAccepted Version - Kim_2014.pdf
", "abstract": "In work related to the electrocatalysis of the CO_2 reduction reactions, we recently reported in This Journal the structure and composition of a Cu(100) electrode surface, pre-dosed at low levels of O_(2(g)) to simulate a Cu electrocatalyst unprotected from air, before and after immersion in alkaline electrolyte at fairly negative potentials to ascertain if an oxide-to-metal reduction reaction can be effected; experimental measurements were based upon ex situ techniques, low-energy electron diffraction (LEED) and Auger electron spectroscopy (AES). It was found that the mildly oxided surface remained ordered and could be cathodically reduced back to a well-ordered oxide-free Cu(100); the quality of the LEED pattern and AES spectrum was less than ideal, however, due to small amounts of base electrolyte remnant in the emersed layer. In this Short Communication, we present results from operando electrochemical scanning tunneling microscopy (EC-STM) that not only confirm the earlier observations but, more importantly, depict more accurately the actual electrocatalysis conditions. An as-received commercially oriented Cu(100) disk that had not been protected from air was observed to consist of narrow terraces encrusted with highly disordered oxides. Cyclic voltammetry and coulometry showed that the oxidized surface consisted of five monolayers of CuO and quarter of a monolayer of Cu_2O. Upon complete cathodic reduction of the interfacial oxides, the surface was found to have reverted to a single-crystalline Cu(100)-(1\u00d71) structure. It may thus be inferred that, under the conditions of electrochemical CO_2 reduction, the Cu catalyst would exist as a zerovalent metal.", "date": "2014-11-15", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "734", "publisher": "Elsevier", "pagerange": "7-9", "id_number": "CaltechAUTHORS:20141001-103653915", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141001-103653915", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2014.09.010", "primary_object": { "basename": "Kim_2014.pdf", "url": "https://authors.library.caltech.edu/records/bwfxg-fe555/files/Kim_2014.pdf" }, "pub_year": "2014", "author_list": "Kim, Youn-Geun and Soriaga, Manuel P." }, { "id": "https://authors.library.caltech.edu/records/y34fg-0jw82", "eprint_id": 52427, "eprint_status": "archive", "datestamp": "2023-08-22 14:04:05", "lastmod": "2023-10-18 19:51:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Van-Campen-D-G", "name": { "family": "Van Campen", "given": "D. G." } }, { "id": "Miller-C-E", "name": { "family": "Miller", "given": "C. E." }, "orcid": "0000-0002-9380-4838" }, { "id": "Jones-R-J-R", "name": { "family": "Jones", "given": "R. J. R." }, "orcid": "0000-0002-4629-3115" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "S. K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Mehta-A", "name": { "family": "Mehta", "given": "A." } } ] }, "title": "High-throughput synchrotron X-ray diffraction for combinatorial phase mapping", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial materials science; high-throughput phase mapping; X-ray diffraction; X-ray fluorescence", "note": "\u00a9 2014 International Union of Crystallography.\n\nReceived 17 May 2014; accepted 16 July 2014.\n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy (Award No. DE-SC0004993). Use\nof the Stanford Synchrotron Radiation Lightsource, SLAC\nNational Accelerator Laboratory, is supported by the US\nDepartment of Energy, Office of Science, Office of Basic\nEnergy Sciences under Contract No. DE-AC02-76SF00515.\nThe authors thank Drs Matthew Kramer and Ichiro Takeuchi\nfor insightful discussions on technique development. The\nauthors also thank Drs Carla Gomes, Ronan Le Bras and\nBruce van Dover for assistance with data processing..\n\nPublished - pp5055.pdf
", "abstract": "Discovery of new materials drives the deployment of new technologies. Complex technological requirements demand precisely tailored material functionalities, and materials scientists are driven to search for these new materials in compositionally complex and often non-equilibrium spaces containing three, four or more elements. The phase behavior of these high-order composition spaces is mostly unknown and unexplored. High-throughput methods can offer strategies for efficiently searching complex and multi-dimensional material genomes for these much needed new materials and can also suggest a processing pathway for synthesizing them. However, high-throughput structural characterization is still relatively under-developed for rapid material discovery. Here, a synchrotron X-ray diffraction and fluorescence experiment for rapid measurement of both X-ray powder patterns and compositions for an array of samples in a material library is presented. The experiment is capable of measuring more than 5000 samples per day, as demonstrated by the acquisition of high-quality powder patterns in a bismuth-vanadium-iron oxide composition library. A detailed discussion of the scattering geometry and its ability to be tailored for different material systems is provided, with specific attention given to the characterization of fiber textured thin films. The described prototype facility is capable of meeting the structural characterization needs for the first generation of high-throughput material genomic searches.", "date": "2014-11", "date_type": "published", "publication": "Journal of Synchrotron Radiation", "volume": "21", "number": "6", "publisher": "International Union of Crystallography", "pagerange": "1262-1268", "id_number": "CaltechAUTHORS:20141205-093300451", "issn": "0909-0495", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141205-093300451", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-76SF00515" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1107/S1600577514016488", "primary_object": { "basename": "pp5055.pdf", "url": "https://authors.library.caltech.edu/records/y34fg-0jw82/files/pp5055.pdf" }, "pub_year": "2014", "author_list": "Gregoire, J. M.; Van Campen, D. G.; et el." }, { "id": "https://authors.library.caltech.edu/records/gf5cw-3yq39", "eprint_id": 120629, "eprint_status": "archive", "datestamp": "2023-08-22 14:07:38", "lastmod": "2023-10-23 17:52:23", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McDonald-Michael-B", "name": { "family": "McDonald", "given": "Michael B." } }, { "id": "Ardo-Shane", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Freund-Michael-S", "name": { "family": "Freund", "given": "Michael S." }, "orcid": "0000-0003-1104-2292" } ] }, "title": "Use of Bipolar Membranes for Maintaining Steady-State pH Gradients in Membrane-Supported, Solar-Driven Water Splitting", "ispublished": "pub", "full_text_status": "public", "keywords": "General Energy; General Materials Science; General Chemical Engineering; Environmental Chemistry", "note": "M.S.F. and M.B.M. acknowledge support by the Natural Sciences and Engineering Research Council (NSERC) of Canada, the Canada Research Chair program, the Province of Manitoba's Science and Technology International Collaboration Fund, and the University of Manitoba. This research made use of the Manitoba Institute for Materials facility, which is supported by the Canada Foundation for Innovation (CFI), the Manitoba Research and Innovation Fund, and the University of Manitoba. N.S.L. and S.A. acknowledge support by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. S.A. also acknowledges partial support from the United States Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under the EERE Fuel Cell Technologies Program. We also acknowledge Nathan Craig, Adam Nielander, and Carl Koval for helpful discussions.\n\nMcDonald, M.B., Ardo, S., Lewis, N.S. and Freund, M.S. (2015), Corrigendum: Use of Bipolar Membranes for Maintaining Steady-State pH Gradients in Membrane-Supported, Solar-Driven Water Splitting. ChemSusChem, 8: 14-14. https://doi.org/10.1002/cssc.201403359", "abstract": "A bipolar membrane can maintain a steady-state pH difference between the sites of oxidation and reduction in membrane-supported, solar-driven water-splitting systems without changing the overall thermodynamics required to split water. A commercially available bipolar membrane that can serve this purpose has been identified, its performance has been evaluated quantitatively, and is demonstrated to meet the requirements for this application. For effective utilization in integrated solar-driven water-splitting systems, such bipolar membranes must, however, be modified to simultaneously optimize their physical properties such as optical transparency, electronic conductivity and kinetics of water dissociation.", "date": "2014-11", "date_type": "published", "publication": "ChemSusChem", "volume": "7", "number": "11", "publisher": "Wiley", "pagerange": "3021-3027", "id_number": "CaltechAUTHORS:20230330-372386000.2", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230330-372386000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Natural Sciences and Engineering Research Council of Canada (NSERC)" }, { "agency": "Canada Research Chairs Program" }, { "agency": "Manitoba Science and Technology International Collaboration Fund" }, { "agency": "University of Manitoba" }, { "agency": "Canada Foundation for Innovation" }, { "agency": "Manitoba Research and Innovation Fund" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201402288", "pub_year": "2014", "author_list": "McDonald, Michael B.; Ardo, Shane; et el." }, { "id": "https://authors.library.caltech.edu/records/m5g7m-q7k59", "eprint_id": 51160, "eprint_status": "archive", "datestamp": "2023-08-20 03:25:55", "lastmod": "2023-10-18 16:07:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans J." }, "orcid": "0000-0001-8433-9471" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Interplay of light transmission and catalytic exchange current in photoelectrochemical systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 AIP Publishing LLC. \n\nReceived 19 August 2014; accepted 15 October 2014; published online 27 October 2014.\n\nThe authors are grateful to Matthias May, Thomas Hannappel, Frank Dimroth, and David Lackner for their contributions in the development of the tandem-electrocatalyst system that stimulated this research. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. K.T.F. was supported by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1144469.\n\nPublished - 1.4900612.pdf
", "abstract": "We develop an analytic current-voltage expression for a variable junction photoelectrochemical (PEC) cell and use it to investigate and illustrate the influence of the optical and electrical properties of catalysts on the optoelectronic performance of PEC devices. Specifically, the model enables a simple, yet accurate accounting of nanostructured catalyst optical and electrical properties through incorporation of an optical transmission factor and active catalytic area factor. We demonstrate the utility of this model via the output power characteristics of an exemplary dual tandem solar cell with indium gallium phosphide and indium gallium arsenide absorbers with varying rhodium catalyst nanoparticle loading. The approach highlights the importance of considering interactions between independently optimized components for optimal PEC device design.", "date": "2014-10-27", "date_type": "published", "publication": "Applied Physics Letters", "volume": "105", "number": "17", "publisher": "American Institute of Physics", "pagerange": "Art. No. 173901", "id_number": "CaltechAUTHORS:20141103-094055916", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141103-094055916", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4900612", "primary_object": { "basename": "1.4900612.pdf", "url": "https://authors.library.caltech.edu/records/m5g7m-q7k59/files/1.4900612.pdf" }, "pub_year": "2014", "author_list": "Fountaine, Katherine T.; Lewerenz, Hans J.; et el." }, { "id": "https://authors.library.caltech.edu/records/mkdav-ywh06", "eprint_id": 49040, "eprint_status": "archive", "datestamp": "2023-08-20 03:23:40", "lastmod": "2023-10-17 20:37:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Javier-A", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Li-Ding", "name": { "family": "Li", "given": "Ding" } }, { "id": "Cruz-J", "name": { "family": "Cruz", "given": "Juan" } }, { "id": "Binamira-Soriaga-E", "name": { "family": "Binamira-Soriaga", "given": "Elizabeth" } }, { "id": "Balbuena-P-B", "name": { "family": "Balbuena", "given": "Perla B." } }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "C\u2013H activation and metalation at electrode surfaces: 2,3-dimethyl-1,4-dihydroxybenzene on Pd(pc) and Pd(111) studied by TLE, HREELS and DFT", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 15 Jul 2014, Accepted 05 Aug 2014,\nFirst published online 06 Aug 2014.\n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, as follows: The surface organometallic work, spectroscopic\ninterpretations and DFT analysis were supported\nthrough the Office of Science of the U.S. Department of Energy\nunder Award No. DE-SC0004993; the TLE and HREELS experiments\nwere supported by the Texas A&M University-CONACYT\nprogram (MPS).\n\nPublished - c4dt02137a.pdf
", "abstract": "Previous studies, based on thin-layer electrochemistry (TLE), in situ scanning tunneling microscopy (EC-STM), high-resolution electron energy loss spectroscopy (HREELS) and density functional theory (DFT) computations, on the chemical adsorption of hydroquinone from aqueous solutions onto atomically smooth Pd (and Pt) electrode surfaces indicated two modes of attachment that depended upon the solution concentration. At low activities, the diphenol was oxidatively chemisorbed as benzoquinone in a flat orientation, suggestive of a Pd(2,3,5,6-\u03b7-C_6H_4O_2) surface complex; at higher concentrations, vertical chemisorption was effected via two C\u2013H bond activations (or metalations) at the 2 and 3 ring positions, evocative of an o-phenylene organopalladium compound. We have extended the work to 2,3-dimethyl-1,4-dihydroxybenzene on Pd(pc) and Pd(111) electrodes to probe the effect of two methyl substituents on only one side of the diphenol ring. Surface coverage and adsorbed-molecule cross section data from TLE and HREELS measurements revealed non-random concentration-dependent adsorbate orientations similar to the oxidative chemisorption of hydroquinone: flat at low concentrations and edgewise at elevated concentrations. The DFT results suggested that, for the flat structure, surface coordination is via the two double bonds of the quinone ring as in [Pd(2,3,5,6-\u03b7)-2,3-dimethyl-p-quinone]. For the edge-vertical orientation, a structure analogous to an o-phenylene compound is generated in which C\u2013H bonds at the 5 and 6 ring positions are activated and then metalated. DFT-simulated HREELS spectra helped identify the observed peaks that distinguish the surface-coordinated quinone from the surface-metalated diphenol.", "date": "2014-10-21", "date_type": "published", "publication": "Dalton Transactions", "volume": "43", "number": "39", "publisher": "Royal Society of Chemistry", "pagerange": "14798-14805", "id_number": "CaltechAUTHORS:20140829-081408528", "issn": "1477-9226", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140829-081408528", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Texas A&M University-CONACYT" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c4dt02137a", "primary_object": { "basename": "c4dt02137a.pdf", "url": "https://authors.library.caltech.edu/records/mkdav-ywh06/files/c4dt02137a.pdf" }, "pub_year": "2014", "author_list": "Javier, Alnald; Li, Ding; et el." }, { "id": "https://authors.library.caltech.edu/records/bgpw8-ms378", "eprint_id": 52215, "eprint_status": "archive", "datestamp": "2023-08-22 13:56:40", "lastmod": "2023-10-18 19:40:15", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Discovery of New Oxygen Evolution Reaction Electrocatalysts by Combinatorial Investigation of the Ni\u2013La\u2013Co\u2013Ce Oxide Composition Space", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial chemistry; electrochemistry; heterogeneous catalysis; oxygen evolution reaction; solar fuels", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived: May 21, 2014; Published online on July 22, 2014. \n\nThis manuscript is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation \nHub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Chris Karp for assistance with electrolyzer testbed Faradaic efficiency and headspace measurements; Natalie Becerra for preliminary SEM and EDS measurements; Martin Marcin for assistance with assembly of high throughput electrochemistry experiments; Karl Walczak for preparation of the NiMo cathode used in the testbed system; Slobodan Mitrovic and Manuel Soriaga for assistance with XPS; and the U. S. Army Research Laboratory for providing the anion exchange membrane used in the testbed\nsystem.\n\nSupplemental Material - celc_201402149_sm_miscellaneous_information.pdf
", "abstract": "We report a new family of earth-abundant electrocatalysts for the oxygen evolution reaction (OER) discovered via high-throughput screening of 1771 discrete metal oxide compositions covering the nickel\u2013lanthanum\u2013cobalt\u2013cerium composition space. The catalytic performance of each of these compositions was measured under conditions applicable to distributed solar fuel generation using a three-electrode scanning-drop electrochemical cell. These high-throughput measurements show enhanced activity for catalyst compositions containing 20\u201365 metal atom\u2009% Ce. The catalytic activity and stability of a representative highly active composition (Ni_(0.1)La_(0.1)Co_(0.3)Ce_(0.5))O_x was verified by standard rotating-disc electrochemistry. Catalysts of this composition showed stable operational performance at 10 mA\u2009cm^(\u22122) for 2 h and survived a 100 h endurance test in a testbed electrolyzer.", "date": "2014-10-14", "date_type": "published", "publication": "ChemElectroChem", "volume": "1", "number": "10", "publisher": "Wiley", "pagerange": "1613-1617", "id_number": "CaltechAUTHORS:20141201-102711064", "issn": "2196-0216", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141201-102711064", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/celc.201402149", "primary_object": { "basename": "celc_201402149_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/bgpw8-ms378/files/celc_201402149_sm_miscellaneous_information.pdf" }, "pub_year": "2014", "author_list": "Haber, Joel A.; Guevarra, Dan; et el." }, { "id": "https://authors.library.caltech.edu/records/z4k47-pzs59", "eprint_id": 48846, "eprint_status": "archive", "datestamp": "2023-08-22 13:45:25", "lastmod": "2023-10-17 20:28:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Han-Lihao", "name": { "family": "Han", "given": "Lihao" }, "orcid": "0000-0002-0452-3381" }, { "id": "Abdi-F-F", "name": { "family": "Abdi", "given": "Fatwa F." } }, { "id": "van-de-Krol-R", "name": { "family": "van de Krol", "given": "Roel" }, "orcid": "0000-0003-4399-399X" }, { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Dam-B", "name": { "family": "Dam", "given": "Bernard" } }, { "id": "Zeman-M", "name": { "family": "Zeman", "given": "Miro" } }, { "id": "Smets-A-H-M", "name": { "family": "Smets", "given": "Arno H. M." } } ] }, "title": "Efficient Water-Splitting Device Based on a Bismuth Vanadate Photoanode and Thin-Film Silicon Solar Cells", "ispublished": "pub", "full_text_status": "public", "keywords": "electrochemistry; photochemistry; silicon; solar cells; water splitting", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: May 23, 2014; Revised: June 19, 2014.\n\nFinancial support from the VIDI project of A.H.M.S. granted by\nthe NWO-STW and European Commission's Framework Project 7\n(NanoPEC, Project 227179) are gratefully acknowledged. R.L.,\nZ.H., and H.-J.L. are supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993.\n\nPublished - Han_2014p2832.pdf
", "abstract": "A hybrid photovoltaic/photoelectrochemical (PV/PEC) water-splitting device with a benchmark solar-to-hydrogen conversion efficiency of 5.2\u2009% under simulated air mass (AM) 1.5 illumination is reported. This cell consists of a gradient-doped tungsten\u2013bismuth vanadate (W:BiVO_4) photoanode and a thin-film silicon solar cell. The improvement with respect to an earlier cell that also used gradient-doped W:BiVO4 has been achieved by simultaneously introducing a textured substrate to enhance light trapping in the BiVO4 photoanode and further optimization of the W gradient doping profile in the photoanode. Various PV cells have been studied in combination with this BiVO_4 photoanode, such as an amorphous silicon (a-Si:H) single junction, an a-Si:H/a-Si:H double junction, and an a-Si:H/nanocrystalline silicon (nc-Si:H) micromorph junction. The highest conversion efficiency, which is also the record efficiency for metal oxide based water-splitting devices, is reached for a tandem system consisting of the optimized W:BiVO_4 photoanode and the micromorph (a-Si:H/nc-Si:H) cell. This record efficiency is attributed to the increased performance of the BiVO_4 photoanode, which is the limiting factor in this hybrid PEC/PV device, as well as better spectral matching between BiVO_4 and the nc-Si:H cell.", "date": "2014-10", "date_type": "published", "publication": "ChemSusChem", "volume": "7", "number": "10", "publisher": "Wiley", "pagerange": "2832-2838", "id_number": "CaltechAUTHORS:20140825-111015375", "issn": "1864-5631", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-111015375", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Nederlandse Organisatie voor Wetenschappelijk Onderzoek (NWO)" }, { "agency": "European Research Council (ERC)", "grant_number": "227179" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/cssc.201402456", "primary_object": { "basename": "Han_2014p2832.pdf", "url": "https://authors.library.caltech.edu/records/z4k47-pzs59/files/Han_2014p2832.pdf" }, "pub_year": "2014", "author_list": "Han, Lihao; Abdi, Fatwa F.; et el." }, { "id": "https://authors.library.caltech.edu/records/2nyxw-mwc81", "eprint_id": 48864, "eprint_status": "archive", "datestamp": "2023-08-20 03:04:02", "lastmod": "2023-10-17 20:29:38", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Pala-R-A", "name": { "family": "Pala", "given": "Ragip A." } }, { "id": "Leenheer-A-J", "name": { "family": "Leenheer", "given": "Andrew J." } }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael" }, "orcid": "0000-0002-0710-7068" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Measurement of minority-carrier diffusion lengths using wedge-shaped semiconductor photoelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 Royal Society of Chemistry 2014. \n\nReceived 22 May 2014, Accepted 29 July 2014. First published online 29 July 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We thank C. Garland for advice on polishing techniques. \n\nElectronic supplementary information (ESI) available: Additional equations for photocurrent calculations, XRD for WO_3 deposited at various temperature, optical determination of thickness profile, cyclic voltammetry scan of WO_3 electrodes, and further details on the ALD processing and polishing. See DOI: 10.1039/c4ee01580k\n\nPublished - c4ee01580k.pdf
Supplemental Material - c4ee01580k1.pdf
", "abstract": "Measurement of the photocurrent as a function of the thickness of a light absorber has been shown herein both theoretically and experimentally to provide a method for determination of the minority-carrier diffusion length of a sample. To perform the measurement, an illuminated spot of photons with an energy well above the band gap of the material was scanned along the thickness gradient of a wedge-shaped, rear-illuminated semiconducting light absorber. Photogenerated majority carriers were collected through a back-side transparent ohmic contact, and a front-side liquid or Schottky junction collected the photogenerated minority carriers. Calculations showed that the diffusion length could be evaluated from the exponential variation in photocurrent as a function of the thickness of the sample. Good agreement was observed between experiment and theory for a solid-state silicon Schottky junction measured using this method. As an example for the application of the technique to semiconductor/liquid-junction photoelectrodes, the minority-carrier diffusion length was determined for graded thickness, sputtered tungsten trioxide and polished bismuth vanadate films under back-illumination in contact with an aqueous electrolyte. This wedge technique does not require knowledge of the spectral absorption coefficient, doping, or surface recombination velocity of the sample.", "date": "2014-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "3424-3430", "id_number": "CaltechAUTHORS:20140825-152741705", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-152741705", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C4EE01580K", "primary_object": { "basename": "c4ee01580k.pdf", "url": "https://authors.library.caltech.edu/records/2nyxw-mwc81/files/c4ee01580k.pdf" }, "related_objects": [ { "basename": "c4ee01580k1.pdf", "url": "https://authors.library.caltech.edu/records/2nyxw-mwc81/files/c4ee01580k1.pdf" } ], "pub_year": "2014", "author_list": "Pala, Ragip A.; Leenheer, Andrew J.; et el." }, { "id": "https://authors.library.caltech.edu/records/4p0aq-va764", "eprint_id": 48727, "eprint_status": "archive", "datestamp": "2023-08-23 16:54:57", "lastmod": "2023-10-17 20:23:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Walczak-K", "name": { "family": "Walczak", "given": "Karl" } }, { "id": "Singh-M-R", "name": { "family": "Singh", "given": "Meenesh R." }, "orcid": "0000-0002-3638-8866" }, { "id": "Karp-C", "name": { "family": "Karp", "given": "Chris" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" } ] }, "title": "An experimental and modeling/simulation-based evaluation of the efficiency and operational performance characteristics of an integrated, membrane-free, neutral pH solar-driven water-splitting system", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 16th June 2014. Accepted 24th July 2014. First published online 25 Jul 2014. \n\nThis material is based upon work performed by the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub,\nsupported through the Office of Science of the U.S. Department\nof Energy under Award Number DE-SC0004993.\n\nPublished - c4ee01824a.pdf
Supplemental Material - c4ee01824a1.pdf
", "abstract": "The efficiency limits, gas-crossover behavior, formation of local pH gradients near the electrode surfaces, and safety characteristics have been evaluated experimentally as well as by use of multi-physics modeling and simulation methods for an integrated solar-driven water-splitting system that operates with bulk electrolyte solutions buffered at near-neutral pH. The integrated membrane-free system utilized a triple-junction amorphous hydrogenated Si (a-Si:H) cell as the light absorber, Pt and cobalt phosphate (Co\u2013Pi) as electrocatalysts for the hydrogen-evolution reaction (HER) and oxygen-evolution reaction (OER), respectively, and a bulk aqueous solution buffered at pH = 9.2 by 1.0 M of boric acid/borate as an electrolyte. Although the solar-to-electrical efficiency of the stand-alone triple-junction a-Si:H photovoltaic cell was 7.7%, the solar-to-hydrogen (STH) conversion efficiency for the integrated membrane-free water-splitting system was limited under steady-state operation to 3.2%, and the formation of pH gradients near the electrode surfaces accounted for the largest voltage loss. The membrane-free system exhibited negligible product-recombination loss while operating at current densities near 3.0 mA cm^(\u22122), but exhibited significant crossover of products (up to 40% H_2 in the O_2 chamber), indicating that the system was not intrinsically safe. A system that contained a membrane to minimize the gas crossover, but which was otherwise identical to the membrane-free system, yielded very low energy-conversion efficiencies at steady state, due to low transference numbers for protons across the membranes resulting in electrodialysis of the solution and the consequent formation of large concentration gradients of both protons and buffer counterions near the electrode surfaces. The modeling and simulation results showed that despite the addition of 1.0 M of buffering agent to the bulk of the solution, during operation significant pH gradients developed near the surfaces of the electrodes. Hence, although the bulk electrolyte was buffered to near-neutral pH, the electrode surfaces and electrocatalysts experienced local environments under steady-state operation that were either highly acidic or highly alkaline in nature, changing the chemical form of the electrocatalysts and exposing the electrodes to potentially corrosive local pH conditions. In addition to significant pH gradients, the STH conversion efficiency of both types of systems was limited by the mass transport of ionic species to the electrode surfaces. Even at operating current densities of <3 mA cm^(\u22122), the voltage drops due to these pH gradients exceeded the combined electrocatalyst overpotentials for the hydrogen- and oxygen-evolution reactions at current densities of 10 mA cm^(\u22122). Hence, such near-neutral pH solar-driven water-splitting systems were both fundamentally limited in efficiency and/or co-evolved explosive mixtures of H_2(g) and O_2(g) in the presence of active catalysts for the recombination of H_2(g) and O_2(g).", "date": "2014-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "3371-3380", "id_number": "CaltechAUTHORS:20140820-110452543", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140820-110452543", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c4ee01824a", "primary_object": { "basename": "c4ee01824a.pdf", "url": "https://authors.library.caltech.edu/records/4p0aq-va764/files/c4ee01824a.pdf" }, "related_objects": [ { "basename": "c4ee01824a1.pdf", "url": "https://authors.library.caltech.edu/records/4p0aq-va764/files/c4ee01824a1.pdf" } ], "pub_year": "2014", "author_list": "Jin, Jian; Walczak, Karl; et el." }, { "id": "https://authors.library.caltech.edu/records/fr6k2-kgx11", "eprint_id": 49692, "eprint_status": "archive", "datestamp": "2023-08-20 03:04:45", "lastmod": "2023-10-17 22:05:14", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Stabilization of n-cadmium telluride photoanodes for water oxidation to O_2(g) in aqueous alkaline electrolytes using amorphous TiO_2 films formed by atomic-layer deposition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Royal Society of Chemistry. \n\nReceived 20th June 2014; accepted 21st August 2014. First published online 22 Aug 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U. S. Department of Energy under Award Number DE-SC0004993. The authors gratefully acknowledge Dr Ke Sun for insightful discussions and Dr Slobodan Mitrovic for assistance collecting XPS data. AIC is grateful to the National Science Foundation for support from an NSF Graduate Research Fellowship. BSB and HBG acknowledge\nthe Beckman Institute Materials and Laser Resource Centers\nand NSF CHE-1305124 for support.\n\nPublished - c4ee01914h.pdf
Supplemental Material - c4ee01914h1.pdf
", "abstract": "Although II\u2013VI semiconductors such as CdS, CdTe, CdSe, ZnTe, and alloys thereof can have nearly ideal band gaps and band-edge positions for the production of solar fuels, II\u2013VI photoanodes are well-known to be unstable towards photocorrosion or photopassivation when in contact with aqueous electrolytes. Atomic-layer deposition (ALD) of amorphous, \"leaky\" TiO_2 films coated with thin films or islands of Ni oxide has been shown to robustly protect Si, GaAs, and other III\u2013V materials from photocorrosion and therefore to facilitate the robust, solar-driven photoelectrochemical oxidation of H_2O to O_2(g). We demonstrate herein that ALD-deposited 140 nm thick amorphous TiO_2 films also effectively protect single crystalline n-CdTe photoanodes from corrosion or passivation. An n-CdTe/TiO_2 electrode with a thin overlayer of a Ni-oxide based oxygen-evolution electrocatalyst produced 435 \u00b1 15 mV of photovoltage with a light-limited current density of 21 \u00b1 1 mA cm^\u22122 under 100 mW cm^\u22122 of simulated Air Mass 1.5 illumination. The ALD-deposited TiO_2 films are highly optically transparent and electrically conductive. We show that an n-CdTe/TiO_2/Ni oxide electrode enables the stable solar-driven oxidation of H_2O to O_2(g) in strongly alkaline aqueous solutions, where passive, intrinsically safe, efficient systems for solar-driven water splitting can be operated.", "date": "2014-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "3334-3337", "id_number": "CaltechAUTHORS:20140915-092918358", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140915-092918358", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Caltech Beckman Institute" }, { "agency": "NSF", "grant_number": "CHE-1305124" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C4EE01914H", "primary_object": { "basename": "c4ee01914h1.pdf", "url": "https://authors.library.caltech.edu/records/fr6k2-kgx11/files/c4ee01914h1.pdf" }, "related_objects": [ { "basename": "c4ee01914h.pdf", "url": "https://authors.library.caltech.edu/records/fr6k2-kgx11/files/c4ee01914h.pdf" } ], "pub_year": "2014", "author_list": "Lichterman, Michael F.; Carim, Azhar I.; et el." }, { "id": "https://authors.library.caltech.edu/records/7hsq8-3g478", "eprint_id": 45110, "eprint_status": "archive", "datestamp": "2023-08-22 13:43:01", "lastmod": "2023-10-26 17:33:58", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Grimm-R-L", "name": { "family": "Grimm", "given": "Ronald L." }, "orcid": "0000-0003-0407-937X" }, { "id": "Warren-E-L", "name": { "family": "Warren", "given": "Emily L." }, "orcid": "0000-0001-8568-7881" }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Comparison between the measured and modeled hydrogen-evolution activity of Ni- or Pt-coated silicon photocathodes", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Silicon; Photoelectrochemistry; Photocatalysis; HER; Interface; Solar fuels", "note": "\u00a9 2014, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. \n\nReceived 10 October 2013; Received in revised form 19 December 2013; Accepted 24 December 2013; Available online 13 April 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. JRM acknowledges graduate research fellowship support from the U.S. Department of Energy, Office of Science. Research was in part carried out at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. Z.H. thanks Prof. Steve Maldonado, Joseph Beardslee, Heather Audesirk and Craig Wiggenhorn for their assistance with the experiments and for helpful discussions.", "abstract": "The electrocatalytic behavior of Ni and Pt nanoparticles for the hydrogen-evolution reaction (HER) on p-type Si photocathodes was measured experimentally and the current density vs. potential (J\u2013E) characteristics of a general metal catalyst on p-Si was modeled as a combination of a Si photodiode in series electrically with metal electrocatalysts. Relative to the rest potential, the J\u2013E characteristics produced by the model showed an increase in total overpotential required to reach a specified current density for the metallized photoelectrodes relative to that of a metal electrode. This prediction was in accord with the experimentally observed behavior of Pt on p-Si, but was in contrast to the behavior observed for Ni on p-Si. Properly accounting for junction energetics and kinetics of the HER is critical to accurate predictions of the solar-to-hydrogen (STH) energy-conversion efficiency of metallized integrated photoelectrochemical systems. Further, models that accurately predict the performance of metal catalysts on semiconductor light absorbers are required to optimize the catalytic performance of metallized photoelectrodes.", "date": "2014-09-23", "date_type": "published", "publication": "International Journal of Hydrogen Energy", "volume": "39", "number": "28", "publisher": "Elsevier", "pagerange": "16220-16226", "id_number": "CaltechAUTHORS:20140422-103752009", "issn": "0360-3199", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140422-103752009", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.ijhydene.2013.12.162", "pub_year": "2014", "author_list": "Huang, Zhuangqun; McKone, James R.; et el." }, { "id": "https://authors.library.caltech.edu/records/hh58q-9ph72", "eprint_id": 47878, "eprint_status": "archive", "datestamp": "2023-08-20 02:56:16", "lastmod": "2023-10-26 21:19:31", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Electrocatalysis of the hydrogen-evolution reaction by electrodeposited amorphous cobalt selenide films", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry. \n\nReceived 25th May 2014. Accepted 11th June 2014. First published online 24 Jul 2014. \n\nThis material is based in part upon work performed by the Joint Center for Artificial photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U. S. Department of Energy under Award Number DE-SC0004993. The authors gratefully acknowledge Dr S. Mitrovic for assistance with X-ray photoelectron spectra acquisition, R. Gerhart for\nassistance with cell fabrication and Dr J. H. Baricuatro for\ninsightful discussions. AIC recognizes a Graduate Research\nFellowship from the National Science Foundation for support.\n\nPublished - c4ta02611j.pdf
Supplemental Material - c4ta02611j1.pdf
", "abstract": "Using an electrochemical method under ambient conditions, crystallographically amorphous films of cobalt selenide have been deposited from aqueous solution onto planar Ti supports. These films have been evaluated as electrocatalysts for the hydrogen-evolution reaction. In 0.500 M H_2SO_4, the cobalt selenide films required an overpotential of ~135 mV to drive the hydrogen-evolution reaction at a benchmark current density of \u221210 mA cm^(\u22122). Galvanostatic measurements indicated stability of the electrocatalytic films for >16 h of continuous operation at \u221210 mA cm^(\u22122). The facile preparation method, and the activity of the cobalt selenide films, suggest that electrodeposited metal chalcogenides are potentially attractive earth-abundant electrocatalysts for the hydrogen-evolution reaction.", "date": "2014-09-14", "date_type": "published", "publication": "Journal of Materials Chemistry A", "volume": "2", "number": "34", "publisher": "Royal Society of Chemistry", "pagerange": "13835-13839", "id_number": "CaltechAUTHORS:20140804-095437360", "issn": "2050-7488", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140804-095437360", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C4TA02611J", "primary_object": { "basename": "c4ta02611j.pdf", "url": "https://authors.library.caltech.edu/records/hh58q-9ph72/files/c4ta02611j.pdf" }, "related_objects": [ { "basename": "c4ta02611j1.pdf", "url": "https://authors.library.caltech.edu/records/hh58q-9ph72/files/c4ta02611j1.pdf" } ], "pub_year": "2014", "author_list": "Carim, Azhar I.; Saadi, Fadl H.; et el." }, { "id": "https://authors.library.caltech.edu/records/rt9d5-8e422", "eprint_id": 47873, "eprint_status": "archive", "datestamp": "2023-08-20 02:42:08", "lastmod": "2023-10-26 21:19:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Carim-Azhar-I", "name": { "family": "Carim", "given": "Azhar I." }, "orcid": "0000-0003-3630-6872" }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." }, "orcid": "0000-0002-9210-344X" }, { "id": "McCrory-Charles-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Operando Synthesis of Macroporous Molybdenum Diselenide Films for Electrocatalysis of the Hydrogen-Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "keywords": "hydrogen-evolution reaction, synthesis of molybdenum diselenide, wet-chemical synthesis of layered electrocatalysts,\nmesoporous catalysts, synthesis of group VI dichalcogenides", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: December 16, 2013. Revised: July 17, 2014. Published: July 17, 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a U.S. Department of Energy (DOE) Energy Innovation Hub, supported through the Office of Science of the DOE via Grant DE-SC0004993. A.I.C. acknowledges a National Science Foundation Graduate Research Fellowship for support.\n\nSupplemental Material - cs500412u_si_001.pdf
", "abstract": "The catalytically inactive components of a film have been converted, through an operando method of synthesis, to produce a catalyst for the reaction that the film is catalyzing. Specifically, thin films of molybdenum diselenide have been synthesized using a two-step wet-chemical method, in which excess sodium selenide was first added to a solution of ammonium heptamolydbate in aqueous sulfuric acid, resulting in the spontaneous formation of a black precipitate that contained molybdenum triselenide (MoSe_3), molybdenum trioxide (MoO_3), and elemental selenium. After purification and after the film had been drop cast onto a glassy carbon electrode, a reductive potential was applied to the precipitate-coated electrode. Hydrogen evolution occurred within the range of potentials applied to the electrode, but during the initial voltammetric cycle, an overpotential of ~400 mV was required to drive the hydrogen-evolution reaction at a benchmark current density of \u221210 mA cm^(\u20132). The overpotential required to evolve hydrogen at the benchmark rate progressively decreased with subsequent voltammetry cycles, until a steady state was reached at which only ~250 mV of overpotential was required to pass \u221210 mA cm^(\u20132) of current density. During the electrocatalysis, the catalytically inactive components in the as-prepared film were (reductively) converted to MoSe_2 through an operando method of synthesis of the hydrogen-evolution catalyst. The initial film prepared from the precipitate was smooth, but the converted film was completely covered with pores ~200 nm in diameter. The porous MoSe_2 film was stable while being assessed by cyclic voltammetry for 48 h, and the overpotential required to sustain 10 mA cm^(\u20132) of hydrogen evolution increased by <50 mV over this period of operation.", "date": "2014-09", "date_type": "published", "publication": "ACS Catalysis", "volume": "4", "number": "9", "publisher": "American Chemical Society", "pagerange": "2866-2873", "id_number": "CaltechAUTHORS:20140804-090046189", "issn": "2155-5435", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140804-090046189", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "primary_object": { "basename": "cs500412u_si_001.pdf", "url": "https://authors.library.caltech.edu/records/rt9d5-8e422/files/cs500412u_si_001.pdf" }, "pub_year": "2014", "author_list": "Saadi, Fadl H.; Carim, Azhar I.; et el." }, { "id": "https://authors.library.caltech.edu/records/4mn6r-dch38", "eprint_id": 50466, "eprint_status": "archive", "datestamp": "2023-08-20 02:45:04", "lastmod": "2023-10-17 23:49:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Calvet-W", "name": { "family": "Calvet", "given": "Wolfram" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Pettenkofer-C", "name": { "family": "Pettenkofer", "given": "Christian" } } ] }, "title": "Model experiments on growth modes and interface electronics of CuInS_2: Ultrathin epitaxial films on GaAs(100) substrates", "ispublished": "pub", "full_text_status": "restricted", "keywords": "band alignment, chalcopyrites, CuInS2, interfaces, thin films", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. \n\nReceived 31 October 2013, revised 16 June 2014, accepted 20 June 2014, Published online 23 July 2014. \n\nThe authors gratefully acknowledge technical support by S. Kubala, H. Sehnert, A. Porsinger, and U. Pettenkofer and a valuable discussion with C. Lehmann, D. Tonti, R. Hunger, and I. Lauermann.", "abstract": "The heterojunction formation between GaAs(100) and CuInS_2 is investigated using ultraviolet photoelectron spectroscopy (UPS), X-ray photoelectron spectroscopy (XPS), and low energy electron diffraction (LEED). Thin layers of CuInS_2 films were deposited in a step-by-step process on wet chemically pre-treated GaAs(100) surfaces by molecular beam epitaxy (MBE) with a total upper thickness limit of the films of 60\u2009nm. The film growth starts from a sulfur-rich GaAs(100) surface. XPS core level analysis of the substrate and film reveals initially a transitory growth regime with the formation of a Ga containing chalcopyrite phase. With increasing film thickness, a change in stoichiometry from Cu-poor to Cu-rich composition is observed. The evaluation of the LEED data shows the occurrence of a recrystallization process where the film orientation follows that of the substrate with the epitaxial relation GaAs{100}||CuInS_2{001}. On the completed junction with a CuInS_2 film thickness of 60\u2009nm, the band discontinuities of the GaAs(100)/CuInS_2 structure measured with XPS and UPS were determined as \u0394E_V\u2009=\u20090.1\u2009\u00b1\u20090.1\u2009eV and \u0394E_C\u2009=\u20090.0\u2009\u00b1\u20090.1\u2009eV, thus showing a type II band alignment.", "date": "2014-09", "date_type": "published", "publication": "Physica Status Solidi A", "volume": "211", "number": "9", "publisher": "Wiley", "pagerange": "1981-1990", "id_number": "CaltechAUTHORS:20141017-073927206", "issn": "1862-6300", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141017-073927206", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/pssa.201330429", "pub_year": "2014", "author_list": "Calvet, Wolfram; Lewerenz, Hans-Joachim; et el." }, { "id": "https://authors.library.caltech.edu/records/mhzgr-bbg02", "eprint_id": 48856, "eprint_status": "archive", "datestamp": "2023-08-20 02:38:54", "lastmod": "2023-10-17 20:29:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McDowell-M-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Sharp-I-D", "name": { "family": "Sharp", "given": "Ian D." }, "orcid": "0000-0001-5238-7487" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Improved Stability of Polycrystalline Bismuth Vanadate Photoanodes by Use of Dual-Layer Thin TiO_2/Ni Coatings", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: June 20, 2014; Revised: August 6, 2014; Published: August 7, 2014. \n\nThis material is based upon work performed at the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology.\n\nSupplemental Material - jp506133y_si_001.pdf
", "abstract": "Ultrathin dual layers of TiO_2 and Ni have been used to stabilize polycrystalline BiVO_4 photoanodes against photocorrosion in an aqueous alkaline (pH = 13) electrolyte. Conformal, amorphous TiO_2 layers were deposited on BiVO_4 thin films by atomic-layer deposition, with Ni deposited onto the TiO_2 by sputtering. Under simulated air mass 1.5 illumination, the dual-layer coating extended the lifetime of the BiVO4 photoanodes during photoelectrochemical water oxidation from minutes, for bare BiVO4, to hours, for the modified electrodes. X-ray photoelectron spectroscopy showed that these layers imparted chemical stability to the semiconductor/electrolyte interface. Transmission electron microscopy revealed the structure and morphology of the polycrystalline BiVO_4 film as well as of the thin coating layers. This work demonstrates that protection schemes based on ultrathin corrosion-resistant overlayers can be applied beneficially to polycrystalline photoanode materials under conditions relevant to efficient solar-driven water-splitting systems.", "date": "2014-08-28", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "34", "publisher": "American Chemical Society", "pagerange": "19618-19624", "id_number": "CaltechAUTHORS:20140825-134317366", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140825-134317366", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp506133y", "primary_object": { "basename": "jp506133y_si_001.pdf", "url": "https://authors.library.caltech.edu/records/mhzgr-bbg02/files/jp506133y_si_001.pdf" }, "pub_year": "2014", "author_list": "McDowell, Matthew T.; Lichterman, Michael F.; et el." }, { "id": "https://authors.library.caltech.edu/records/a2dyt-4jc21", "eprint_id": 49836, "eprint_status": "archive", "datestamp": "2023-08-20 02:36:20", "lastmod": "2023-10-17 22:15:00", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "May-M-M", "name": { "family": "May", "given": "Matthias M." }, "orcid": "0000-0002-1252-806X" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Hannappel-T", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" } ] }, "title": "Optical in Situ Study of InP(100) Surface Chemistry: Dissociative Adsorption of Water and Oxygen", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: March 25, 2014. Revised: July 30, 2014. Published: July 30, 2014. \n\nM.M.M. acknowledges Studienstiftung des deutschen Volkes\nfor his scholarship. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: parts of the organization of the work, of the discussion, as well as of the manuscript wording and composition were supported through the Office of Science of the U.S. Department of Energy under Award DESC0004993.\n\nPublished - jp502955m.pdf
Supplemental Material - jp502955m_si_001.pdf
", "abstract": "Semiconductors designated for solar water-splitting need to be simultaneously stable and efficient in the charge transfer over the interface to the aqueous electrolyte. Although InP(100) has been employed as photocathode for several decades, no experimental data on its initial interaction with water is available. We study reaction mechanisms of well-defined surfaces with water and oxygen employing photoelectron and in situ reflection anisotropy spectroscopy. Our findings show that reaction path and stability differ significantly with atomic surface reconstruction. While the mixed-dimer In-rich surface exhibits dissociative water adsorption featuring In\u2013O\u2013P rather than unfavorable In\u2013O\u2013In bond topologies, the H-terminated, P-rich surface reconstruction is irreversibly removed. Oxygen exposure attacks the In-rich surface more efficiently and additionally modifies, unlike water exposure, bulk-related optical transitions. Hydroxyl is not observed, which suggests a dehydrogenation of adsorbed species already at ambient temperature. Our findings may benefit the design of InP(100) surfaces for photoelectrochemical water splitting.", "date": "2014-08-21", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "33", "publisher": "American Chemical Society", "pagerange": "19032-19041", "id_number": "CaltechAUTHORS:20140918-144401465", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140918-144401465", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Studienstiftung des deutschen Volkes" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp502955m", "primary_object": { "basename": "jp502955m.pdf", "url": "https://authors.library.caltech.edu/records/a2dyt-4jc21/files/jp502955m.pdf" }, "related_objects": [ { "basename": "jp502955m_si_001.pdf", "url": "https://authors.library.caltech.edu/records/a2dyt-4jc21/files/jp502955m_si_001.pdf" } ], "pub_year": "2014", "author_list": "May, Matthias M.; Lewerenz, Hans-Joachim; et el." }, { "id": "https://authors.library.caltech.edu/records/yny2z-2pb07", "eprint_id": 50146, "eprint_status": "archive", "datestamp": "2023-08-20 02:23:32", "lastmod": "2023-10-17 22:48:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Yikai", "name": { "family": "Chen", "given": "Yikai" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Modeling the Performance of an Integrated Photoelectrolysis System with 10\u00d7 Solar Concentrators", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited.\n\nManuscript submitted June 13, 2014; revised manuscript received July 10, 2014. Published August 1, 2014.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The authors thank John C. Stevens for helpful discussion regarding the optics of solar concentrator designs. Authors Yikai Chen and Chengxiang Xiang contributed equally to this work.\n\nPublished - J._Electrochem._Soc.-2014-Chen-F1101-10.pdf
", "abstract": "Two designs for an integrated photoelectrolysis system that uses a 10\u00d7 concentrating solar collector have been investigated in detail. The system performance was evaluated using a multi-physics model that accounted for the properties of the tandem photoabsorbers, mass transport, and the electrocatalytic performance of the oxygen-evolution and hydrogen-evolution reactions (OER and HER, respectively). The solar-to-hydrogen (STH) conversion efficiencies and the ohmic losses associated with proton transport in the solution electrolyte and through the membrane of the photoelectrolysis system were evaluated systematically as a function of the cell dimensions, the operating temperatures, the bandgap combinations of the tandem cell, and the performance of both the photoabsorbers and electrocatalysts. Relative to designs of optimized systems that would operate without a solar concentrator, the optimized 10\u00d7 solar concentrator designs possessed larger ohmic losses and exhibited less uniformity in the distribution of the current density along the width of the photoelectrode. To minimize resistive losses while maximizing the solar-to-hydrogen conversion efficiency, \u03b7_(STH), both of the designs, a two-dimensional \"trough\" design and a three-dimensional \"bubble wrap\" design, required that the electrode width or diameter, respectively, was no larger than a few millimeters. As the size of the electrodes increased beyond this limiting dimension, the \u03b7_(STH) became more sensitive to the performance of the photoabsorbers and catalysts. At a fixed electrode dimension, increases in the operating temperature reduced the efficiency of cells with smaller electrodes, due to degradation in the performance of the photoabsorber with increasing temperature. In contrast, cells with larger electrode dimensions showed increases in efficiency as the temperature increased, due to increases in the rates of electrocatalysis and due to enhanced mass transport. The simulations indicted that cells that contained 10% photoabsorber area, and minimal amounts of Nafion or other permselective membranes (i.e. areal coverages and volumetric fractions of only a few percent of the cell), with the remaining area comprised of a suitable, low-cost inert, non porous material (flexible polymers, inert inorganic materials, etc.) should be able to produce high values of \u03b7_(STH), with \u03b7_(STH) = 29.8% for an optimized design with a bandgap combination of 1.6 eV/0.9 eV in a tandem photoabsorber system at 350 K.", "date": "2014-08-01", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "161", "number": "10", "publisher": "Electrochemical Society", "pagerange": "F1101-F1110", "id_number": "CaltechAUTHORS:20141001-112924015", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20141001-112924015", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.0751410jes", "primary_object": { "basename": "J._Electrochem._Soc.-2014-Chen-F1101-10.pdf", "url": "https://authors.library.caltech.edu/records/yny2z-2pb07/files/J._Electrochem._Soc.-2014-Chen-F1101-10.pdf" }, "pub_year": "2014", "author_list": "Chen, Yikai; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/6nncm-kjd85", "eprint_id": 45500, "eprint_status": "archive", "datestamp": "2023-08-20 01:33:41", "lastmod": "2023-10-26 18:01:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "McCrory-Charles-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Sanabria-Chinchilla-Jean", "name": { "family": "Sanabria-Chinchilla", "given": "Jean" } }, { "id": "Crouthers-Danielle-J", "name": { "family": "Crouthers", "given": "Danielle" } }, { "id": "Darensbourg-Marcetta-Y", "name": { "family": "Darensbourg", "given": "Marcetta Y." }, "orcid": "0000-0002-0070-2075" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Heterogenization of a Water-Insoluble Molecular Complex for Catalysis of the Proton-Reduction Reaction in Highly Acidic Aqueous Solutions", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2014 Springer Science+Business Media New York.\n\nPublished online: 26 April 2014.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: except for the synthesis of the di-iron complexes which was funded by the National Science Foundation (CHE-091679 and CHE-1266097) (MYD), all the work was supported through the Office of Science of the US Department of Energy under Award No. DE-SC0004993.", "abstract": "Our long-held interest in the resiliency of electrochemical\nfunctionalities upon surface immobilization has herded us\nfrom directly chemisorbed electroactive moieties, to\nanchor group-leashed redox-active couples and to\nsurface-tethered enzyme-inspired molecular catalysts.\nThe latter represent the most intricate because the electrocatalytic activities involve mixed-valence states and may require certain entatic (fractionally rotated) configurations. In this regard, we recently investigated the proton-reduction electrocatalysis by hydrogenase-inspired di-iron complexes at polycrystalline and (111)-faceted Au electrodes.", "date": "2014-07", "date_type": "published", "publication": "Electrocatalysis", "volume": "5", "number": "3", "publisher": "Springer", "pagerange": "226-228", "id_number": "CaltechAUTHORS:20140505-132735594", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140505-132735594", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-091679" }, { "agency": "NSF", "grant_number": "CHE-1266097" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-014-0200-7", "pub_year": "2014", "author_list": "Baricuatro, Jack H.; Kim, Youn-Geun; et el." }, { "id": "https://authors.library.caltech.edu/records/9ewrk-hjs64", "eprint_id": 47876, "eprint_status": "archive", "datestamp": "2023-08-20 01:04:41", "lastmod": "2023-10-26 21:19:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Liu-Rui", "name": { "family": "Liu", "given": "Rui" } }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua" }, "orcid": "0000-0002-2987-0865" }, { "id": "Yan-Xiaogang", "name": { "family": "Yang", "given": "Xiaogang" } } ] }, "title": "Enhanced photoelectrochemical water-splitting performance of semiconductors by surface passivation layers", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry. Received 8th February 2014. Accepted 30th May 2014. The authors would like to acknowledge Dr. Bruce S. Brunschwig from Molecular Materials Research Center in California Institution of Technology for his valuable comments and suggestions to\nimprove the manuscript. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, and Xuchang University, as follows: Rui Liu and Joshua Spurgeon are supported through the Office of Science of the U.S. Department of Energy under Award no. DESC0004993; Zhi Zheng and Xiaogang Yang are supported by Henan Province office of education (14B150013), Innovation Scientists and Technicians Troop Construction Projects of Henan Province (Grant no. 144200510014) and National Natural Science\nFoundation of China under Grant no. 21273192.\n\nPublished - c4ee00450g.pdf
", "abstract": "An important approach for solving the world's sustainable energy challenges is the conversion of solar energy to chemical fuels. Semiconductors can be used to convert/store solar energy to chemical bonds in an energy-dense fuel. Photoelectrochemical (PEC) water-splitting cells, with semiconductor electrodes, use sunlight and water to generate hydrogen. Herein, recent studies on improving the efficiency of semiconductor-based solar water-splitting devices by the introduction of surface passivation layers are reviewed. We show that passivation layers have been used as an effective strategy to improve the charge-separation and transfer processes across semiconductor\u2013liquid interfaces, and thereby increase overall solar energy conversion efficiencies. We also summarize the demonstrated passivation effects brought by these thin layers, which include reducing charge recombination at surface states, increasing the reaction kinetics, and protecting the semiconductor from chemical corrosion. These benefits of passivation layers play a crucial role in achieving highly efficient water-splitting devices in the near future.", "date": "2014-05-30", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "2014", "number": "7", "publisher": "Royal Society of Chemistry", "pagerange": "2504-2517", "id_number": "CaltechAUTHORS:20140804-092046492", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140804-092046492", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Henan Province office of education", "grant_number": "14B150013" }, { "agency": "Henan Province Technicians Troop Construction Projects", "grant_number": "144200510014" }, { "agency": "National Natural Science Foundation of China", "grant_number": "21273192" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C4EE00450G", "primary_object": { "basename": "c4ee00450g.pdf", "url": "https://authors.library.caltech.edu/records/9ewrk-hjs64/files/c4ee00450g.pdf" }, "pub_year": "2014", "author_list": "Liu, Rui; Spurgeon, Joshua; et el." }, { "id": "https://authors.library.caltech.edu/records/fqd0g-9fy53", "eprint_id": 45771, "eprint_status": "archive", "datestamp": "2023-08-20 01:03:35", "lastmod": "2023-10-26 18:27:12", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Beardslee-J-A", "name": { "family": "Beardslee", "given": "Joseph A." } }, { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael" }, "orcid": "0000-0002-0710-7068" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Amorphous TiO_2 coatings stabilize Si, GaAs, and GaP photoanodes for efficient water oxidation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Association for the Advancement of Science. \n\nReceived for publication 28 January 2014. Accepted for publication 1 May 2014. \n\nThis work is supported through the Office of Science of the U.S. Department of Energy (DOE) under award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. M.S. acknowledges the Resnick Sustainability Institute for a graduate fellowship, and B.S.B. acknowledges the Beckman Institute at the California Institute of Technology for support. XPS was performed at the Molecular Materials Research Center in the Beckman Institute at the California Institute of Technology. TEM imaging and spectroscopy were performed at the Center for Electron Microscopy and Microanalysis, University of Southern California. We thank H.- J. Lewerenz, C. Koval, and F. Houle for fruitful discussions; Y. Guan for secondary-ion mass spectrometry measurements; S. R. Nutt for use of the microscopy and microanalysis facility; P. D. Dapkus for the use of the metal-organic chemical vapor deposition facility; S. Ardo for help in boron-diffusion doping; and K. Papadantonakis for assistance with editing this manuscript. The authors' institution (California Institute of Technology) has filed a provisional U.S. patent application directly relating to the work described in the paper (patent application no. 61/889,430, filed on 10 October 2013).\n\nSupplemental Material - Hu.S.SM.pdf
", "abstract": "Although semiconductors such as silicon (Si), gallium arsenide (GaAs), and gallium phosphide (GaP) have band gaps that make them efficient photoanodes for solar fuel production, these materials are unstable in aqueous media. We show that TiO_2 coatings (4 to 143 nanometers thick) grown by atomic layer deposition prevent corrosion, have electronic defects that promote hole conduction, and are sufficiently transparent to reach the light-limited performance of protected semiconductors. In conjunction with a thin layer or islands of Ni oxide electrocatalysts, Si photoanodes exhibited continuous oxidation of 1.0 molar aqueous KOH to O_2 for more than 100 hours at photocurrent densities of >30 milliamperes per square centimeter and ~100% Faradaic efficiency. TiO_2-coated GaAs and GaP photoelectrodes exhibited photovoltages of 0.81 and 0.59 V and light-limiting photocurrent densities of 14.3 and 3.4 milliamperes per square centimeter, respectively, for water oxidation.", "date": "2014-05-30", "date_type": "published", "publication": "Science", "volume": "344", "number": "6187", "publisher": "American Association for the Advancement of Science", "pagerange": "1005-1009", "id_number": "CaltechAUTHORS:20140515-133039268", "issn": "0036-8075", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140515-133039268", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1126/science.1251428", "primary_object": { "basename": "Hu.S.SM.pdf", "url": "https://authors.library.caltech.edu/records/fqd0g-9fy53/files/Hu.S.SM.pdf" }, "pub_year": "2014", "author_list": "Hu, Shu; Shaner, Matthew R.; et el." }, { "id": "https://authors.library.caltech.edu/records/0sxw5-s8n54", "eprint_id": 45504, "eprint_status": "archive", "datestamp": "2023-08-20 00:59:06", "lastmod": "2023-10-26 18:02:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lacy-D-C", "name": { "family": "Lacy", "given": "David C." } }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Studies of Cobalt-Mediated Electrocatalytic CO_2 Reduction Using a Redox-Active Ligand", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Chemical Society. ACS AuthorChoice - This is an open access article published under an ACS AuthorChoice License, which permits copying and redistribution of the article or any adaptations for non-commercial purposes. \n\nReceived: December 30, 2013; Published: April 28, 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993.\nD.C.L. would also like to acknowledge the National Institutes\nof Health (Award Number F32GM106726). The authors\nwould also like to thank Tzu-Pin Lin, Michael Takase, and\nLawrence Henling for help with crystallography, and Kyle\nCummins and Slobodan Mitrovic for help with XPS. Clifford\nKubiak is also thanked for many insightful discussions.\n\nPublished - ic403122j.pdf
Supplemental Material - ic403122j_si_001.cif
Supplemental Material - ic403122j_si_002.pdf
", "abstract": "The cobalt complex [Co^(III)N_4H(Br)_2]+ (N_4H = 2,12-dimethyl-3,7,11,17-tetraazabicyclo-[11.3.1]-heptadeca-1(7),2,11,13,15-pentaene) was used for electrocatalytic CO_2 reduction in wet MeCN with a glassy carbon working electrode. When water was employed as the proton source (10 M in MeCN), CO was produced (f_(CO)= 45% \u00b1 6.4) near the Co^(I/0) redox couple for [Co^(III)N_4H(Br)_2]+ (E_(1/2) = \u22121.88 V FeCp_2^(+/0)) with simultaneous H_2 evolution (f_(H2)= 30% \u00b1 7.8). Moreover, we successfully demonstrated that the catalytically active species is homogeneous through the use of control experiments and XPS studies of the working glassy-carbon electrodes. As determined by cyclic voltammetry, CO_2 catalysis occurred near the formal CoI/0redox couple, and attempts were made to isolate the triply reduced compound (\"[Co^0N_4H]\"). Instead, the doubly reduced (\"Co^I\") compounds [CoN4] and [CoN_4H(MeCN)]+ were isolated and characterized by X-ray crystallography. Their molecular structures prompted DFT studies to illuminate details regarding their electronic structure. The results indicate that reducing equivalents are stored on the ligand, implicating redox noninnocence in the ligands for H_2 evolution and CO_2 reduction electrocatalysis.", "date": "2014-05-19", "date_type": "published", "publication": "Inorganic Chemistry", "volume": "53", "number": "10", "publisher": "American Chemical Society", "pagerange": "4980-4988", "id_number": "CaltechAUTHORS:20140505-142420147", "issn": "0020-1669", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140505-142420147", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NIH Predoctoral Fellowship", "grant_number": "F32GM106726" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ic403122j", "pmcid": "PMC4033636", "primary_object": { "basename": "ic403122j.pdf", "url": "https://authors.library.caltech.edu/records/0sxw5-s8n54/files/ic403122j.pdf" }, "related_objects": [ { "basename": "ic403122j_si_001.cif", "url": "https://authors.library.caltech.edu/records/0sxw5-s8n54/files/ic403122j_si_001.cif" }, { "basename": "ic403122j_si_002.pdf", "url": "https://authors.library.caltech.edu/records/0sxw5-s8n54/files/ic403122j_si_002.pdf" } ], "pub_year": "2014", "author_list": "Lacy, David C.; McCrory, Charles C. L.; et el." }, { "id": "https://authors.library.caltech.edu/records/9amps-pev49", "eprint_id": 44341, "eprint_status": "archive", "datestamp": "2023-08-20 00:53:06", "lastmod": "2023-10-26 00:24:30", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hsieh-Chung-Hung", "name": { "family": "Hsieh", "given": "Chung-Hung" } }, { "id": "Ding-Shengda", "name": { "family": "Ding", "given": "Shengda" } }, { "id": "Erdem-\u00d6-F", "name": { "family": "Erdem", "given": "\u00d6zlen F." } }, { "id": "Crouthers-D-J", "name": { "family": "Crouthers", "given": "Danielle J." } }, { "id": "Liu-Tianbiao", "name": { "family": "Liu", "given": "Tianbiao" } }, { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Lubitz-W", "name": { "family": "Lubitz", "given": "Wolfgang" }, "orcid": "0000-0001-7059-5327" }, { "id": "Popescu-C-V", "name": { "family": "Popescu", "given": "Codrina V." } }, { "id": "Reibenspies-J-H", "name": { "family": "Reibenspies", "given": "Joseph H." } }, { "id": "Hall-M-B", "name": { "family": "Hall", "given": "Michael B." } }, { "id": "Darensbourg-M-Y", "name": { "family": "Darenbourg", "given": "Marcetta Y." } } ] }, "title": "Redox active iron nitrosyl units in proton reduction electrocatalysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Macmillan Publishers Limited. \n\nReceived 11 November 2013; Accepted 18 March 2014; Published 02 May 2014. \n\nWe are grateful for financial support from the National Science Foundation (CHE-1266097 to M.Y.D., CHE-0910552 to M.B.H. and CHE-0956779 to C.V.P.) and the R.A. Welch Foundation (A-0924 to M.Y.D. and A-0648 to M.B.H.). We acknowledge Gudrun Klihm for EPR technical support and financial support from the EU/Energy Network Project SOLAR-H2 (FP7 contract 212508) and the Max Planck Society (to \u00d6.F.E. and W.L.). Bulk electrolysis measurements are based in part on work performed at the Joint Center for Artificial Photosynthesis, a DOE Innovation Hub, supported through the Office of Science of the US Department of Energy under Award Number DE-SC0004993. \n\nC.-H.H. and M.Y.D. performed synthesis and characterization; S.D. and M.B.H. performed computational studies; D.J.C., T.L. and C.C.L.M. performed the electrochemical studies and hydrogen detection; \u00d6.F.E. and W.L. performed the EPR measurements and interpretation; C.V.P. performed the Mossbauer measurements; The X-ray crystal structures were determined by C.-H.H. and J.H.R. The manuscript was drafted by all with final edits by S.D., M.Y.D. and M.B.H. \n\nThe authors declare no competing financial interests. \n\nAccession codes: The X-ray crystallographic coordinates for structures reported in this Article have been deposited at the Cambridge Crystallographic Data Centre (CCDC), under deposition number CCDC940518 (1red). These data can be obtained free of charge from The Cambridge Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_request/cif.\n\nSupplemental Material - ncomms4684-s1.pdf
Supplemental Material - ncomms4684-s2.cif
", "abstract": "Base metal, molecular catalysts for the fundamental process of conversion of protons and electrons to dihydrogen, remain a substantial synthetic goal related to a sustainable energy future. Here we report a diiron complex with bridging thiolates in the butterfly shape of the 2Fe2S core of the [FeFe]-hydrogenase active site but with nitrosyl rather than carbonyl or cyanide ligands. This binuclear [(NO)Fe(N_2S_2)Fe(NO)_2]+ complex maintains structural integrity in two redox levels; it consists of a (N_2S_2)Fe(NO) complex (N_2S_2=N,N\u2032-bis(2-mercaptoethyl)-1,4-diazacycloheptane) that serves as redox active metallodithiolato bidentate ligand to a redox active dinitrosyl iron unit, Fe(NO)_2. Experimental and theoretical methods demonstrate the accommodation of redox levels in both components of the complex, each involving electronically versatile nitrosyl ligands. An interplay of orbital mixing between the Fe(NO) and Fe(NO)_2 sites and within the iron nitrosyl bonds in each moiety is revealed, accounting for the interactions that facilitate electron uptake, storage and proton reduction.", "date": "2014-05-02", "date_type": "published", "publication": "Nature Communications", "volume": "5", "publisher": "Nature Publishing Group", "pagerange": "Art. No. 3684", "id_number": "CaltechAUTHORS:20140314-123801645", "issn": "2041-1723", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140314-123801645", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "NSF", "grant_number": "CHE-1266097" }, { "agency": "NSF", "grant_number": "CHE-0910552" }, { "agency": "NSF", "grant_number": "CHE-0956779" }, { "agency": "Robert A. Welch Foundation", "grant_number": "A-0924" }, { "agency": "Robert A. Welch Foundation", "grant_number": "A-0648" }, { "agency": "EU/Energy Network Project SOLAR-H2", "grant_number": "212508" }, { "agency": "Max Planck Society" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1038/ncomms4684", "primary_object": { "basename": "ncomms4684-s1.pdf", "url": "https://authors.library.caltech.edu/records/9amps-pev49/files/ncomms4684-s1.pdf" }, "related_objects": [ { "basename": "ncomms4684-s2.cif", "url": "https://authors.library.caltech.edu/records/9amps-pev49/files/ncomms4684-s2.cif" } ], "pub_year": "2014", "author_list": "Hsieh, Chung-Hung; Ding, Shengda; et el." }, { "id": "https://authors.library.caltech.edu/records/nrsag-pw466", "eprint_id": 44728, "eprint_status": "archive", "datestamp": "2023-08-20 00:21:05", "lastmod": "2023-10-26 14:54:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Leenheer-A-J", "name": { "family": "Leenheer", "given": "Andrew J." } }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Solar energy conversion via hot electron internal photoemission in metallic nanostructure: Efficiency estimates", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 American Institute of Physics Publishing LLC. Received 31 October 2013; accepted 15 February 2014; published online 1 April 2014. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy\nInnovation Hub, supported through the Office of Science of\nthe U.S. Department of Energy under Award No. DESC0004993.\nP.N. is supported by a National Science\nFoundation Graduate Research Fellowship and by the\nResnick Sustainability Institute.\n\nPublished - 1.4870040.pdf
", "abstract": "Collection of hot electrons generated by the efficient absorption of light in metallic nanostructures, in contact with semiconductor substrates can provide a basis for the construction of solar energy-conversion devices. Herein, we evaluate theoretically the energy-conversion efficiency of systems that rely on internal photoemission processes at metal-semiconductor Schottky-barrier diodes. In this theory, the current-voltage characteristics are given by the internal photoemission yield as well as by the thermionic dark current over a varied-energy barrier height. The Fowler model, in all cases, predicts solar energy-conversion efficiencies of <1% for such systems. However, relaxation of the assumptions regarding constraints on the escape cone and momentum conservation at the interface yields solar energy-conversion efficiencies as high as 1%\u201310%, under some assumed (albeit optimistic) operating conditions. Under these conditions, the energy-conversion efficiency is mainly limited by the thermionic dark current, the distribution of hot electron energies, and hot-electron momentum considerations.", "date": "2014-04-07", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "115", "number": "13", "publisher": "American Institute of Physics", "pagerange": "Art. No. 134301", "id_number": "CaltechAUTHORS:20140408-084811849", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140408-084811849", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1063/1.4870040", "primary_object": { "basename": "1.4870040.pdf", "url": "https://authors.library.caltech.edu/records/nrsag-pw466/files/1.4870040.pdf" }, "pub_year": "2014", "author_list": "Leenheer, Andrew J.; Narang, Prineha; et el." }, { "id": "https://authors.library.caltech.edu/records/8t4ef-w2q72", "eprint_id": 45204, "eprint_status": "archive", "datestamp": "2023-08-20 00:07:43", "lastmod": "2023-10-26 17:51:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Huang-Zhuangqun", "name": { "family": "Huang", "given": "Zhuangqun" } }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Two stories from the ISACS 12 conference: solar-fuel devices and catalyst identification", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\n\nReceived 05 Nov 2013, Accepted 05 Nov 2013.\nFirst published online 16 Jan 2014. \n\nZ. Huang thanks an EES grant for\ntravel and conference expenses and the\nauthors all acknowledge DE-SC0004993\nfor support that allowed preparation of\nthis manuscript.\n\nPublished - c3ee90043f.pdf
", "abstract": "The International Symposia for\nadvancing the Chemical Sciences, a\npartner of the journal Chemical Science,\nheld its 12th meeting (ISACS 12) at the\nUniversity of Cambridge on September\n3\u20136 2013. ISACS 12 focused on \"Challenges\nin Chemical Renewable Energy\",\nwith oral presentations organized along\nfive themes: photovoltaics, solar fuels,\nmolecular and bio-inspired catalysts, new\nmaterials for batteries, and fuel cells.\nISACS 12 also included a presentation on\nthe sugar cane-based energy industry in\nBrazil, a recording by the BBC World\nService, and two poster sessions. This\nconference was an exciting, busy place to\nmeet people, exchange ideas, and foster\ncollaboration.", "date": "2014-04", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "4", "publisher": "Royal Society of Chemistry", "pagerange": "1207-1211", "id_number": "CaltechAUTHORS:20140425-070837177", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140425-070837177", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c3ee90043f", "primary_object": { "basename": "c3ee90043f.pdf", "url": "https://authors.library.caltech.edu/records/8t4ef-w2q72/files/c3ee90043f.pdf" }, "pub_year": "2014", "author_list": "Huang, Zhuangqun; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/t8mpz-mnx02", "eprint_id": 45607, "eprint_status": "archive", "datestamp": "2023-08-20 00:03:05", "lastmod": "2023-10-26 18:06:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Supplie-O", "name": { "family": "Supplie", "given": "Oliver" }, "orcid": "0000-0002-2424-7118" }, { "id": "May-M-M", "name": { "family": "May", "given": "Matthias M." }, "orcid": "0000-0002-1252-806X" }, { "id": "Stange-H", "name": { "family": "Stange", "given": "Helena" } }, { "id": "H\u00f6hn-C", "name": { "family": "H\u00f6hn", "given": "Christian" }, "orcid": "0000-0002-2043-598X" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Hannappel-T", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" } ] }, "title": "Materials for light-induced water splitting: In situ controlled surface preparation of GaPN epilayers grown lattice-matched on Si(100)", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 AIP Publishing LLC. Received 18 December 2013; accepted 8 March 2014; published online 20 March 2014. The authors would like to thank M. Schmidtbauer, L.\nSpie\u00df, and K. Tonisch for advice regarding the XRD analysis\nas well as H. D\u00f6scher for discussions regarding the band\nalignment. This work was supported by the BMBF (Project\nNo. 03SF0404A) and DFG (Project No. HA3096). M. M.\nMay and H. Stange acknowledge scholarships of the\nStudienstiftung des deutschen Volkes e.V. This material is\nbased upon work performed by the Joint Center for Artificial\nPhotosynthesis, a DOE Energy Innovation Hub, as follows:\nparts of the organization of the work, of the discussion as\nwell as of the manuscript wording and composition were\nsupported through the Office of Science of the US\nDepartment of Energy under Award No. DE-SC0004993.\n\nPublished - 1.4869121.pdf
", "abstract": "Energy storage is a key challenge in solar-driven renewable energy conversion. We promote a photochemical diode based on dilute nitride GaPN grown lattice-matched on Si(100), which could reach both high photovoltaic efficiencies and evolve hydrogen directly without external bias. Homoepitaxial GaP(100) surface preparation was shown to have a significant impact on the semiconductor-water interface formation. Here, we grow a thin, pseudomorphic GaP nucleation buffer on almost single-domain Si(100) prior to GaPN growth and compare the GaP_(0.98)N_(0.02)/Si(100) surface preparation to established P- and Ga-rich surfaces of GaP/Si(100). We apply reflection anisotropy spectroscopy to study the surface preparation of GaP_(0.98)N_(0.02) in situ in vapor phase epitaxy ambient and benchmark the signals to low energy electron diffraction, photoelectron spectroscopy, and x-ray diffraction. While the preparation of the Ga-rich surface is hardly influenced by the presence of the nitrogen precursor 1,1-dimethylhydrazine (UDMH), we find that stabilization with UDMH after growth hinders well-defined formation of the V-rich GaP_(0.98)N_(0.02)/Si(100) surface. Additional features in the reflection anisotropy spectra are suggested to be related to nitrogen incorporation in the GaP bulk.", "date": "2014-03-21", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "116", "number": "11", "publisher": "American Institute of Physics", "pagerange": "Art. No. 113509", "id_number": "CaltechAUTHORS:20140508-113013593", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140508-113013593", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03SF0404A" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "HA3096" }, { "agency": "Studienstiftung des deutschen Volkes" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4869121", "primary_object": { "basename": "1.4869121.pdf", "url": "https://authors.library.caltech.edu/records/t8mpz-mnx02/files/1.4869121.pdf" }, "pub_year": "2014", "author_list": "Supplie, Oliver; May, Matthias M.; et el." }, { "id": "https://authors.library.caltech.edu/records/9n51x-geg81", "eprint_id": 47702, "eprint_status": "archive", "datestamp": "2023-08-22 11:57:59", "lastmod": "2023-10-26 21:10:46", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan" }, "orcid": "0000-0002-9592-3195" }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High-Throughput Mapping of the Electrochemical Properties of (Ni-Fe-Co-Ce)O_x Oxygen-Evolution Catalysts", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial chemistry; electrochemistry; heterogeneous catalysis; oxygen evolution reaction; solar fuels", "note": "\u00a9 2014 Wiley-VCH Verlag GmbH & Co. \n\nArticle first published online: 13 Dec 2013. Manuscript Received: 18 Nov 2013. \n\nThis manuscript is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, an Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank Dr. Charles McCrory for assistance with RDE experiments, and Drs. Manuel Soriaga, Alexis T. Bell, Mary Louie, and Yun Cai for helpful discussions.\n\nSupplemental Material - celc_201300229_sm_miscellaneous_information.pdf
", "abstract": "Discovering improved electrocatalysts is critical for many technologically important processes and for the development of new clean-energy technologies. High-throughput methods for measuring fundamental electrochemical properties are demonstrated through the investigation of oxygen-evolution catalysis by using 665 oxide compositions containing nickel, iron, cobalt, and cerium. The behavior of each composition is characterized in 1.0\u2009M NaOH(aq) by using a scanning drop three-electrode cell to perform chronopotentiometry (CP) and cyclic voltammetry experiments. CP measurements at different current densities identify different composition\u2013performance trends, owing to underlying variations in fundamental electrochemical behavior. We report systematic, coincident, composition-dependent trends in the Tafel slopes and the reversible redox potentials of the catalysts. Applying high-throughput electrochemical methods provides insight into composition\u2013property\u2013performance relationships and motivates new directions for the study of catalyst mechanisms by using informatics and theory.", "date": "2014-03-11", "date_type": "published", "publication": "ChemElectroChem", "volume": "1", "number": "3", "publisher": "Wiley", "pagerange": "524-528", "id_number": "CaltechAUTHORS:20140731-100438286", "issn": "2196-0216", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140731-100438286", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1002/celc.201300229", "primary_object": { "basename": "celc_201300229_sm_miscellaneous_information.pdf", "url": "https://authors.library.caltech.edu/records/9n51x-geg81/files/celc_201300229_sm_miscellaneous_information.pdf" }, "pub_year": "2014", "author_list": "Haber, Joel A.; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/r2fnc-ecf12", "eprint_id": 43857, "eprint_status": "archive", "datestamp": "2023-08-19 23:55:05", "lastmod": "2023-10-25 23:56:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel" }, "orcid": "0000-0001-7847-5506" }, { "id": "Marcin-M-R", "name": { "family": "Marcin", "given": "Martin" } }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Mapping Quantum Yield for (Fe\u2212Zn\u2212Sn\u2212Ti)O_x Photoabsorbers Using a High Throughput Photoelectrochemical Screening System", "ispublished": "pub", "full_text_status": "restricted", "keywords": "photoelectrochemistry, metal oxides, semiconductor liquid junction, quantum yield", "note": "\u00a9 2014 American Chemical Society. \n\nReceived: June 21, 2013.\nRevised: October 8, 2013. Publication Date (Web): January 28, 2014. \n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC000499.\nWe gratefully acknowledge critical support and infrastructure\nprovided for this work by the Kavli Nanoscience Institute at\nCaltech.", "abstract": "Combinatorial synthesis and screening of light absorbers are critical to material discoveries for photovoltaic and photoelectrochemical applications. One of the most effective ways to evaluate the energy-conversion properties of a semiconducting light absorber is to form an asymmetric junction and investigate the photogeneration, transport and recombination processes at the semiconductor interface. This standard photoelectrochemical measurement is readily made on a semiconductor sample with a back-side metallic contact (working electrode) and front-side solution contact. In a typical combinatorial material library, each sample shares a common back contact, requiring novel instrumentation to provide spatially resolved and thus sample-resolved measurements. We developed a multiplexing counter electrode with a thin layer assembly, in which a rectifying semiconductor/liquid junction was formed and the short-circuit photocurrent was measured under chopped illumination for each sample in a material library. The multiplexing counter electrode assembly demonstrated a photocurrent sensitivity of sub-10 \u03bcA cm^(\u20132) with an external quantum yield sensitivity of 0.5% for each semiconductor sample under a monochromatic ultraviolet illumination source. The combination of cell architecture and multiplexing allows high-throughput modes of operation, including both fast-serial and parallel measurements. To demonstrate the performance of the instrument, the external quantum yields of 1819 different compositions from a pseudoquaternary metal oxide library, (Fe\u2013Zn\u2013Sn\u2013Ti)O_x, at 385 nm were collected in scanning serial mode with a throughput of as fast as 1 s per sample. Preliminary screening results identified a promising ternary composition region centered at Fe_(0.894)Sn_(0.103)Ti_(0.0034)O_x, with an external quantum yield of 6.7% at 385 nm.", "date": "2014-03-10", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "16", "number": "3", "publisher": "American Chemical Society", "pagerange": "120-127", "id_number": "CaltechAUTHORS:20140218-144233923", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140218-144233923", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC000499" }, { "agency": "Kavli Nanoscience Institute" } ] }, "local_group": { "items": [ { "id": "Kavli-Nanoscience-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1021/co400081w", "pub_year": "2014", "author_list": "Xiang, Chengxiang; Haber, Joel; et el." }, { "id": "https://authors.library.caltech.edu/records/n0n6r-nf464", "eprint_id": 43640, "eprint_status": "archive", "datestamp": "2023-08-22 11:53:30", "lastmod": "2023-10-25 23:44:27", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chmielowiec-Brian", "name": { "family": "Chmielowiec", "given": "Brian" }, "orcid": "0000-0002-3004-9345" }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Javier-Alnald-C", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" }, { "id": "Sun-Guofeng", "name": { "family": "Sun", "given": "Guofeng" } }, { "id": "Darensbourg-Marcetta-Y", "name": { "family": "Darensbourg", "given": "Marcetta Y." }, "orcid": "0000-0002-0070-2075" }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Molecular catalysis that transpires only when the complex is heterogenized: Studies of a hydrogenase complex surface-tethered on polycrystalline and (1 1 1)-faceted gold by EC, PM-FT-IRRAS, HREELS, XPS and STM", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Hydrogen evolution reaction; HER electrocatalysis by surface-attached di-iron hydrogenase complexes; Surface-immobilization-enabled molecular catalysis; Heterogeneous catalysis with homogeneous complexes; Biologically inspired electrocatalysis", "note": "\u00a9 2014 Elsevier B. V. \n\nAvailable online 29 December 2013. \n\nSpecial Issue in Honour of Kingo Itaya. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: Experimental work that involved surface spectroscopy, microscopy and electrochemistry were supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the synthesis and characterization of the di-iron complexes were supported by the National Science Foundation (CHE-0616695) (MYD) and the Texas A&M University-CONACYT program (MPS). The authors would like to thank D. Crouthers for the synthesis work and J. Sanabria-Chinchilla for the initial electrochemical experiments.", "abstract": "The proton-reduction catalytic activity of two di-iron hydrogenase complexes, [(\u03bc-S_(2)C_(3)H_6)[Fe(CO)_3][Fe(CO)_(2)(PPh_3)] (1) and (\u03bc-S_(2)C_(3)H_6)[Fe(CO)_3][Fe(CO)2(PPh2{(CH2)2SH})] (2), was investigated at polycrystalline and (1 1 1)-faceted Au electrodes in nonaqueous electrolyte. Compound (2) was irreversibly tethered to the surface through the single bondSH group; (1) was present only in the unadsorbed (dissolved) state. No enhancement of the proton reduction reaction was observed with the homogeneous complex. Pronounced catalysis was exhibited by the heterogenized (surface-attached) material. Neither increase nor decrease in activity was observed when unadsorbed complex (2) was added to the solution of the heterogenized catalyst. The conclusion from these observations, that no catalysis transpires unless the subject molecular complex is tethered to the electrode surface, is totally unexpected; it runs counter to conventional wisdom that an untethered homogeneous electrocatalyst, especially one that requires a particular entatic (partially rotated) configuration to complete its function, would invariably perform better than its surface-immobilized counterpart. The heterogenized complex, present at rather low coverages due to its sizable adsorbed-molecule cross section, was further investigated by polarization-modulation Fourier transform infrared reflection absorption spectroscopy (PM-FT-IRRAS), high-resolution electron-energy loss spectroscopy (HREELS), X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM). The electrochemistry (EC) and STM results indicated that the catalytic activity of the immobilized complex is a function of its surface coverage but not of its spatial configuration; the catalytic sites are accessible regardless of the particular arrangement of the pendant active site with respect to the surface. The surface-immobilized complex suffered a non-negligible loss in catalytic activity after the ex situ experiments, perhaps due to (partial) decarbonylation.", "date": "2014-03-01", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "716", "publisher": "Elsevier", "pagerange": "63-70", "id_number": "CaltechAUTHORS:20140204-101048359", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140204-101048359", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-0616695" }, { "agency": "Texas A&M University-CONACYT Program" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2013.12.025", "pub_year": "2014", "author_list": "Chmielowiec, Brian; Saadi, Fadl H.; et el." }, { "id": "https://authors.library.caltech.edu/records/dz8hd-vq729", "eprint_id": 44272, "eprint_status": "archive", "datestamp": "2023-08-22 11:53:46", "lastmod": "2023-10-26 00:21:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-Jack-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Ehlers-Charles-B", "name": { "family": "Ehlers", "given": "Charles B." } }, { "id": "Cummins-Kyle-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Soriaga-Manuel-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Stickney-John-L", "name": { "family": "Stickney", "given": "John L." } }, { "id": "Kim-Youn-Geun", "name": { "family": "Kim", "given": "Youn-Geun" }, "orcid": "0000-0002-5936-6520" } ] }, "title": "Structure and composition of Cu(hkl) surfaces exposed to O_2 and emersed from alkaline solutions: Prelude to UHV-EC studies of CO_2 reduction at well-defined copper catalysts", "ispublished": "pub", "full_text_status": "restricted", "keywords": "Surface studies of tri-faceted copper; Copper single-crystal electrodes; Ultrahigh Vacuum-Electrochemistry (UHV-EC); Air oxidation of Cu(hkl) surfaces; Copper emersed from alkaline solutions", "note": "\u00a9 2013 Elsevier B.V. \n\nAvailable online 10 October 2013. \n\nSpecial Issue in Honour of Kingo Itaya. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The surface electrochemistry-spectroscopy analysis and interpretation were supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the preparation and initial surface characterization of the copper tri-crystal electrode were supported by the National Science Foundation, Division of Materials Research (DMR-1006747) (JLS).", "abstract": "The ability of copper electrodes to catalyze the reduction of carbon dioxide better than any single-metal material is now well known. However, it is also an established fact that copper is an efficient scavenger of dry oxygen. Hence, the initiation of the CO_2 reduction reaction at copper must contend with the presence of surface oxides spontaneously formed when the metal is exposed to ambient air. In this regard, the interfacial structures and compositions of Cu(1 0 0), Cu(1 1 0) and Cu(1 1 1), before and after exposure to gaseous oxygen and emersion from in mildly alkaline media (pH 8 and 10), were characterized by a combination of electrochemistry and electron spectroscopy (low-energy electron diffraction and Auger electron spectroscopy). The affinity of the low-index copper planes to oxygen gas was found to decrease in the order Cu(1 1 0) > Cu(1 0 0) > Cu(1 1 1). The same reactivity trend was exhibited by the electrodes emersed from alkaline K_2SO_4 solution. The initial stages of the anodic oxidation of copper, prior to formation of bulk oxides, span a wide potential window that is pH-sensitive; within this precursory region, submonolayer coverages of oxygen tended to form surface domains with long-range order. At potentials far below the anodic-oxidation region (E < \u22120.90 V), the surface compositions and structures of Cu(hkl) are expected to mimic those of zerovalent copper. These results may bear significant implications in the generation as well as identification of surface-bound intermediates that define the electrocatalytic selectivity of copper towards the reduction of molecular species such as CO_2 and CO in alkaline media.", "date": "2014-03-01", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "716", "publisher": "Elsevier", "pagerange": "101-105", "id_number": "CaltechAUTHORS:20140312-092635775", "issn": "1572-6657", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140312-092635775", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "DMR-1006747" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2013.10.001", "pub_year": "2014", "author_list": "Baricuatro, Jack H.; Ehlers, Charles B.; et el." }, { "id": "https://authors.library.caltech.edu/records/q9db1-cwp52", "eprint_id": 43454, "eprint_status": "archive", "datestamp": "2023-08-22 11:53:21", "lastmod": "2023-10-25 23:33:36", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." } }, { "id": "Saadi-Fadl-H", "name": { "family": "Saadi", "given": "Fadl H." }, "orcid": "0000-0003-3941-0464" }, { "id": "Pieterick-Adam-P", "name": { "family": "Pieterick", "given": "Adam P." } }, { "id": "Spurgeon-Joshua-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Synthesis and hydrogen-evolution activity of tungsten selenide thin films deposited on tungsten foils", "ispublished": "pub", "full_text_status": "public", "keywords": "Hydrogen-evolution reaction; Tungsten selenide thin films; Chemical vapor transport; Thin-film electrocatalysts; Synthesis of Group VI dichalcogenides", "note": "\u00a9 2014 Elsevier B.V. \n \nAvailable online 11 December 2013; Special Issue in Honour of Kingo Itaya. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. We also acknowledge the MPR Institute for helpful discussions and assistance in the preparation of this manuscript.\n\nSupplemental Material - Figs._S1-S5.docx
", "abstract": "Thin films of WSe_2 have been deposited onto a conductive substrate (tungsten foil) using a relatively simple chemical-vapor-transport technique. X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy, X-ray powder diffraction, scanning electron microscopy, and high-resolution transmission electron microscopy indicated that the films consisted of micron-sized single crystals of WSe_2 that were oriented perpendicular to the surface of the tungsten foil substrate. Linear sweep voltammetry was used to assess the ability of the WSe_2 films to catalyze the hydrogen-evolution reaction and chronopotentiometry was used to gauge the temporal stability of the catalytic performance of the films under cathodic conditions. A 350 mV overpotential (\u03b7) was required to drive the hydrogen-evolution reaction at a current density of \u221210 mA cm^(\u22122) in aqueous 0.5 M H_2SO_4, representing a significant improvement in catalytic performance relative to the behavior of macroscopic WSe_2 single crystals. The WSe_2 thin films were relatively stable under catalytic conditions, with the overpotential changing by only \u223c10 mV after one hour and exhibiting an additional change of \u223c5mV after another hour of operation.", "date": "2014-03-01", "date_type": "published", "publication": "Journal of Electroanalytical Chemistry", "volume": "716", "publisher": "Elsevier", "pagerange": "45-48", "id_number": "CaltechAUTHORS:20140121-113850320", "issn": "0022-0728", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140121-113850320", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.jelechem.2013.11.030", "primary_object": { "basename": "Figs._S1-S5.docx", "url": "https://authors.library.caltech.edu/records/q9db1-cwp52/files/Figs._S1-S5.docx" }, "pub_year": "2014", "author_list": "Velazquez, Jesus M.; Saadi, Fadl H.; et el." }, { "id": "https://authors.library.caltech.edu/records/a14fd-faw27", "eprint_id": 42895, "eprint_status": "archive", "datestamp": "2023-08-22 11:47:33", "lastmod": "2023-10-25 23:08:03", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Chen-Shiyou", "name": { "family": "Chen", "given": "Shiyou" } }, { "id": "Coronel-N-C", "name": { "family": "Coronel", "given": "Naomi C." } }, { "id": "Gul-S", "name": { "family": "Gul", "given": "Sheraz" }, "orcid": "0000-0001-8920-8737" }, { "id": "Yano-Junko", "name": { "family": "Yano", "given": "Junko" }, "orcid": "0000-0001-6308-9071" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "Bandgap Tunability in Zn(Sn,Ge)N_2 Semiconductor Alloys", "ispublished": "pub", "full_text_status": "public", "keywords": "Zn(Sn,Ge)N_2 semiconductor alloys; miscibility; bandgap", "note": "\u00a9 2013 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.\n\nReceived: September 5, 2013.\n\nArticle first published online: 5 Dec. 2013.\n\nThis material is based upon work performed by the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of Energy under\nAward Number DE-SC0004993, and was also supported by the Dow\nChemical Company. P.N. acknowledges support from a National\nScience Foundation Graduate Research Fellowship and from the Resnick\nSustainability Institute. X-ray spectroscopy work was performed at the\nAdvanced Light Source (ALS, BL 10.3.2 and 7.0.1), Berkeley, under\nContract DE-AC02\u201305CH11231. The authors thank Drs. Jinghua Guo\nand Per-Anders Glans-Suzuki for their support at BL 7.0.1.\n\nSupplemental Material - adma201304473-sup-0001-S1.pdf
", "abstract": "ZnSn_(1-x)Ge_xN_2 direct bandgap semiconductor alloys, with a crystal structure and electronic structure similar to InGaN, are earth-abundant alternatives for efficient, high-quality optoelectronic devices and solar energy conversion. The bandgap is tunable almost monotonically from 2 eV (ZnSnN_2) to 3.1 eV (ZnGeN_2) by control of the Sn/Ge ratio.", "date": "2014-02-26", "date_type": "published", "publication": "Advanced Materials", "volume": "26", "number": "8", "publisher": "Wiley", "pagerange": "1235-1241", "id_number": "CaltechAUTHORS:20131209-100236108", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131209-100236108", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Dow Chemical Company" }, { "agency": "NSF Graduate Research Fellowship" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/adma.201304473", "primary_object": { "basename": "adma201304473-sup-0001-S1.pdf", "url": "https://authors.library.caltech.edu/records/a14fd-faw27/files/adma201304473-sup-0001-S1.pdf" }, "pub_year": "2014", "author_list": "Narang, Prineha; Chen, Shiyou; et el." }, { "id": "https://authors.library.caltech.edu/records/etehb-02v25", "eprint_id": 43320, "eprint_status": "archive", "datestamp": "2023-08-19 23:19:38", "lastmod": "2023-10-25 23:27:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Coridan-R-H", "name": { "family": "Coridan", "given": "Robert H." }, "orcid": "0000-0003-1916-4446" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Photoelectrochemistry of core\u2013shell tandem junction n\u2013p^+-Si/n-WO_3 microwire array photoelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 The Royal Society of Chemistry.\nReceived 10 Sep 2013, Accepted 07 Nov 2013;\nFirst published online 16 Dec 2013.\nThis material is based upon work performed by the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub,\nsupported through the Office of Science of the U.S. Department\nof Energy under Award Number DE-SC0004993. M.S. acknowledges\nthe Resnick Sustainability Institute for a graduate\nfellowship. K.F. is supported by the National Science Foundation\nGraduate Research Fellowship under Grant No. DGE-1144469. S.A. acknowledges support from a U.S. Department\nof Energy, Office of Energy Efficiency and Renewable Energy\n(EERE) Postdoctoral Research Award under the EERE Fuel Cell\nTechnologies Program. The authors would like to thank Dr Shu\nHu for assistance in boron doping, Rick Gerhart for fabrication\nof the electrochemical cells used and Dr Andrew Leenheer for\nthe WO3 refractive index data.\n\nPublished - c3ee43048k.pdf
Supplemental Material - c3ee43048k_si.pdf
", "abstract": "Tandem junction (n\u2013p^+-Si/ITO/WO_3/liquid) core\u2013shell microwire devices for solar-driven water splitting have been designed, fabricated and investigated photoelectrochemically. The tandem devices exhibited open-circuit potentials of E_(\u221d) = \u22121.21 V versus E^0\u2032(O_2/H_2O), demonstrating additive voltages across the individual junctions (n\u2013p^+-Si E_(\u221d) = \u22120.5 V versus solution; WO_3/liquid E_(\u221d) = \u22120.73 V versus E^0\u2032(O_2/H_2O)). Optical concentration (12\u00d7, AM1.5D) shifted the open-circuit potential to E_(\u221d) = \u22121.27 V versus E^0\u2032(O_2/H_2O) and resulted in unassisted H_2 production during two-electrode measurements (anode: tandem device, cathode: Pt disc). The solar energy-conversion efficiencies were very low, 0.0068% and 0.0019% when the cathode compartment was saturated with Ar or H_2, respectively, due to the non-optimal photovoltage and band-gap of the WO_3 that was used in the demonstration system to obtain stability of all of the system components under common operating conditions while also insuring product separation for safety purposes.", "date": "2014-02", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "779-790", "id_number": "CaltechAUTHORS:20140110-150648310", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140110-150648310", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1039/C3EE43048K", "primary_object": { "basename": "c3ee43048k.pdf", "url": "https://authors.library.caltech.edu/records/etehb-02v25/files/c3ee43048k.pdf" }, "related_objects": [ { "basename": "c3ee43048k_si.pdf", "url": "https://authors.library.caltech.edu/records/etehb-02v25/files/c3ee43048k_si.pdf" } ], "pub_year": "2014", "author_list": "Shaner, Matthew R.; Fountaine, Katherine T.; et el." }, { "id": "https://authors.library.caltech.edu/records/nk9pt-j4552", "eprint_id": 44502, "eprint_status": "archive", "datestamp": "2023-08-19 23:22:59", "lastmod": "2023-10-26 14:21:11", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Cai-Yun", "name": { "family": "Cai", "given": "Yun" } }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "Slobodan" }, "orcid": "0000-0001-8913-8505" }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Bell-A-T", "name": { "family": "Bell", "given": "Alexis T." }, "orcid": "0000-0002-5738-4645" }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "Discovering Ce-rich oxygen evolution catalysts, from high throughput screening to water electrolysis", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 Royal Society of Chemistry. \n\nReceived 9th November 2013. Accepted 3rd January 2014. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award no. DE-SC0004993). The authors thank Charles McCrory for assistance with acquisition, analysis and\ninterpretation of traditional electrochemistry on rotating disc electrodes; Dan Guevarra for assistance with high throughput electrochemistry experiments; Paul Newhouse for assistance with preparation of glassy carbon rods for printing; William West and Chris Karp for assistance with electrolyzer testbed faradaic efficiency and headspace measurements; Martin Marcin for assistance with assembly of high throughput electrochemistry experiments; the Microanalytical Center in the College of Chemistry, UC Berkeley for ICP-OES measurements; Karl Walczak for preparation of the NiMo cathode used in the testbed system; and the U. S. Army Research Laboratory for providing the anion exchange membrane used in the testbed system.\n\nSupplemental Material - c3ee43683g.pdf
", "abstract": "We report a new Ce-rich family of active oxygen evolution reaction (OER) catalysts composed of earth abundant elements, discovered using high-throughput methods. High resolution inkjet printing was used to produce 5456 discrete oxide compositions containing the elements nickel, iron, cobalt and cerium. The catalytic performance of each of these compositions was measured under conditions applicable to distributed solar fuels generation using a three-electrode scanning drop electrochemical cell. The catalytic activity and stability of representative compositions (Ni_(0.5)Fe_(0.3)Co_(0.17)Ce_(0.03)O_x and Ni_(0.3)Fe^(0.07)Co_(0.2)Ce_(0.43)O_x) from 2 distinct regions were verified by resynthesizing these compositions on glassy carbon rods for electrochemical testing. The activity of the new Ce-rich catalysts was further verified using an unrelated synthetic method to electrodeposit a pseudo-ternary composition Ni_(0.2)Co_(0.3)Ce_(0.5)O_x, which produced a catalyst with 10 mA cm^(\u22122) oxygen evolution current at 310 mV overpotential. The unique Tafel behavior of these Ce-rich catalysts affords the opportunity for further improvement.", "date": "2014-02", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "7", "number": "2", "publisher": "Royal Society of Chemistry", "pagerange": "682-688", "id_number": "CaltechAUTHORS:20140325-130923791", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140325-130923791", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/C3EE43683G", "primary_object": { "basename": "c3ee43683g.pdf", "url": "https://authors.library.caltech.edu/records/nk9pt-j4552/files/c3ee43683g.pdf" }, "pub_year": "2014", "author_list": "Haber, Joel A.; Cai, Yun; et el." }, { "id": "https://authors.library.caltech.edu/records/5d5kq-kdn76", "eprint_id": 43519, "eprint_status": "archive", "datestamp": "2023-08-19 23:20:14", "lastmod": "2023-10-25 23:37:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "Santosh K." }, "orcid": "0000-0001-8170-2685" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "Joel A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Guevarra-D-W", "name": { "family": "Guevarra", "given": "Dan W." }, "orcid": "0000-0002-9592-3195" }, { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "Ed" } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" } ] }, "title": "High-Throughput Bubble Screening Method for Combinatorial Discovery of Electrocatalysts for Water Splitting", "ispublished": "pub", "full_text_status": "public", "keywords": "high-throughput screening, electrocatalyst, water-splitting, oxygen evolution reaction, inkjet printing", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: November 26, 2013; Revised: December 24, 2013; Publication Date (Web): December 30, 2013. \n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC000499.\n\nSupplemental Material - co400151h_si_001.pdf
", "abstract": "Combinatorial synthesis and screening for discovery of electrocatalysts has received increasing attention, particularly for energy-related technologies. High-throughput discovery strategies typically employ a fast, reliable initial screening technique that is able to identify active catalyst composition regions. Traditional electrochemical characterization via current\u2013voltage measurements is inherently throughput-limited, as such measurements are most readily performed by serial screening. Parallel screening methods can yield much higher throughput and generally require the use of an indirect measurement of catalytic activity. In a water-splitting reaction, the change of local pH or the presence of oxygen and hydrogen in the solution can be utilized for parallel screening of active electrocatalysts. Previously reported techniques for measuring these signals typically function in a narrow pH range and are not suitable for both strong acidic and basic environments. A simple approach to screen the electrocatalytic activities by imaging the oxygen and hydrogen bubbles produced by the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) is reported here. A custom built electrochemical cell was employed to record the bubble evolution during the screening, where the testing materials were subject to desired electrochemical potentials. The transient of the bubble intensity obtained from the screening was quantitatively analyzed to yield a bubble figure of merit (FOM) that represents the reaction rate. Active catalysts in a pseudoternary material library, (Ni\u2013Fe\u2013Co)O_x, which contains 231 unique compositions, were identified in less than one minute using the bubble screening method. An independent, serial screening method on the same material library exhibited excellent agreement with the parallel bubble screening. This general approach is highly parallel and is independent of solution pH.", "date": "2014-02", "date_type": "published", "publication": "ACS Combinatorial Science", "volume": "16", "number": "2", "publisher": "American Chemical Society", "pagerange": "47-52", "id_number": "CaltechAUTHORS:20140127-093320786", "issn": "2156-8952", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140127-093320786", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/co400151h", "primary_object": { "basename": "co400151h_si_001.pdf", "url": "https://authors.library.caltech.edu/records/5d5kq-kdn76/files/co400151h_si_001.pdf" }, "pub_year": "2014", "author_list": "Xiang, Chengxiang; Suram, Santosh K.; et el." }, { "id": "https://authors.library.caltech.edu/records/hmn8z-a2b42", "eprint_id": 44029, "eprint_status": "archive", "datestamp": "2023-08-19 23:09:14", "lastmod": "2023-10-26 00:07:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Warren-E-L", "name": { "family": "Warren", "given": "Emily L." }, "orcid": "0000-0001-8568-7881" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Silicon Microwire Arrays for Solar Energy-Conversion Applications", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: June 25, 2013; Revised: November 1, 2013; Published: December 9, 2013. \n\nThe authors would like to thank many of the researchers who\nhave contributed to the development of Si MW-based energy conversion devices and the work discussed in this article: Brendan Kayes, Michael Filler, James Maiolo, Joshua Spurgeon, Michael Kelzenberg, Morgan Putnam, Kate Plass, Shannon Boettcher, Daniel Turner-Evans, Hal Emmer, Adele Tamboli, Chris Chen, Elizabeth Santori, Ronald Grimm, Matthew Bierman, Heather Audesirk, Joseph Beardslee, Michael Walter, Chengxiang Xiang, Andrew Meng, Shane Ardo, Robert Coridan, Anna Beck, Ryan Briggs, Clara Cho, Leslie O'Leary, and Matthew Shaner. We acknowledge BP (support for E.L.W.), DOE DE-FG02-03-ER15483, and the Joint Center for Artificial Photosynthesis, DOE DE-SC0004993 (support for N.S.L. and H.A.A.), for financial support that allowed the preparation of this manuscript.", "abstract": "Highly structured silicon microwire (Si MW) arrays have been synthesized and characterized as absorbers for solar energy-conversion systems. These materials are of great interest for applications in solar energy conversion, including solar electricity and solar fuels production, due to their unique materials properties, form factors, ease of fabrication, and device-processing attributes. The Si MW array geometry allows for efficient collection of photogenerated carriers from impure materials that have short minority-carrier diffusion lengths while simultaneously allowing for high optical absorption and high external quantum yields for charge-carrier collection. In addition, Si MW arrays exhibit unique mesoscale optical behavior and can be removed from the growth substrate to provide flexible, processable arrays of Si microwires ordered in a variety of organic polymers and ionomers. The unique photon-management properties of Si MW arrays, combined with their high internal surface area and controlled morphology for catalyst placement and support, allow for the use of earth-abundant electrocatalysts to produce an integrated, functional photoelectrode. These materials therefore also provide an opportunity to explore the 3-dimensional photoelectrochemical behavior of fuel-forming microstructured electrodes.", "date": "2014-01-16", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "118", "number": "2", "publisher": "American Chemical Society", "pagerange": "747-759", "id_number": "CaltechAUTHORS:20140227-090625946", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140227-090625946", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "BP" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03-ER15483" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp406280x", "pub_year": "2014", "author_list": "Warren, Emily L.; Atwater, Harry A.; et el." }, { "id": "https://authors.library.caltech.edu/records/mh71n-8b306", "eprint_id": 41845, "eprint_status": "archive", "datestamp": "2023-08-19 23:07:12", "lastmod": "2023-10-25 14:50:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chen-Shiyou", "name": { "family": "Chen", "given": "Shiyou" } }, { "id": "Narang-P", "name": { "family": "Narang", "given": "Prineha" }, "orcid": "0000-0003-3956-4594" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Wang-Lin-Wang", "name": { "family": "Wang", "given": "Lin-Wang" } } ] }, "title": "Phase Stability and Defect Physics of a Ternary ZnSnN_2 Semiconductor: First Principles Insights", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 WILEY-VCH Verlag.\n\nReceived: June 14, 2013\nRevised: July 24, 2013\nPublished online: October 8, 2013\n\nThis material is based upon work performed by the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub, supported\nthrough the Office of Science of the U.S. Department of Energy under\nAward Number DE-SC0004993. Prineha Narang is supported by the\nNational Science Foundation Graduate Research Fellowship and the\nResnick Sustainability Institute.", "abstract": "Direct bandgap, earth abundant semiconductors with Eg\naround 1.5 eV are essential for both photovoltaic and solar to\nfuel (photocatalytic) energy conversion. Among the conventional\nsemiconductors, such as element Si and Ge, binary III-V\n(III = B, Al, Ga, In; V = N, P, As, Sb) and II-VI (II = Zn, Cd;\nVI = O, S, Se, Te), only a limited number of candidates have\nsuitable bandgaps in the range 1.0\u20132.0 eV. This motivates the\nsearch for earth-abundant alternatives to current semiconductors\nfor efficient, high-quality optoelectronic devices, photovoltaics\nand photocatalytic energy conversion. One methodology\nfor the search is to study ternary and multi-ternary semiconductors\nwith more elements and more flexible optoelectronic\nproperties.", "date": "2014-01-15", "date_type": "published", "publication": "Advanced Materials", "volume": "26", "number": "2", "publisher": "Wiley", "pagerange": "311-315", "id_number": "CaltechAUTHORS:20131009-164328252", "issn": "0935-9648", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131009-164328252", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Resnick Sustainability Institute" }, { "agency": "NSF Graduate Research Fellowship" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1002/adma.201302727", "pub_year": "2014", "author_list": "Chen, Shiyou; Narang, Prineha; et el." }, { "id": "https://authors.library.caltech.edu/records/bdpep-gw588", "eprint_id": 44051, "eprint_status": "archive", "datestamp": "2023-08-22 11:27:17", "lastmod": "2023-10-26 00:08:50", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" } ] }, "title": "Will Solar-Driven Water-Splitting Devices See the Light of Day?", "ispublished": "pub", "full_text_status": "restricted", "keywords": "solar fuels; hydrogen evolution; HER; oxygen evolution; OER; photoelectrochemistry; electrocatalysis; semiconductor; ion-exchange membrane", "note": "\u00a9 2013 American Chemical Society.\n\nPublished In Issue January 14, 2014; Article ASAP October 14, 2013; Just Accepted Manuscript August 27, 2013; Received: July 01, 2013; Revised: August 22, 2013.\n\nThis article is part of the Celebrating Twenty-Five Years of Chemistry of Materials special issue.\n\nN.S.L. acknowledges support from the Joint Center for\nArtificial Photosynthesis, a DOE Energy Innovation Hub,\nsupported through the Office of Science of the U.S.\nDepartment of Energy under Award Number DE-SC0004993.\nJ.R.M. and H.B.G. acknowledge the National Science\nFoundation for support through the Powering the Planet\nCenter for Chemical Innovation, Grant CHE-1305124. J.R.M.\nacknowledges the DOE Office of Science for a graduate\nresearch fellowship. The authors thank Dr. Shane Ardo and\nAdam Nielander for helpful comments during the preparation\nof this manuscript.", "abstract": "Through decades of sustained effort, researchers have made substantial progress on developing technologies for solar-driven water splitting. Nevertheless, more basic research is needed before prototype devices with a chance for commercial success can be demonstrated. In this Perspective, we summarize the major design constraints that motivate continued research in the field of solar-driven water splitting. Additionally, we discuss key device components that are now available for use in demonstration systems and prototypes. Finally, we highlight research areas where breakthroughs will be critical for continued progress toward commercial viability for solar-driven water-splitting devices.", "date": "2014-01-14", "date_type": "published", "publication": "Chemistry of Materials", "volume": "26", "number": "1", "publisher": "American Chemical Society", "pagerange": "407-414", "id_number": "CaltechAUTHORS:20140228-085825144", "issn": "0897-4756", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140228-085825144", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-1305124" } ] }, "local_group": { "items": [ { "id": "CCI-Solar-Fuels" }, { "id": "JCAP" } ] }, "doi": "10.1021/cm4021518", "pub_year": "2014", "author_list": "McKone, James R.; Lewis, Nathan S.; et el." }, { "id": "https://authors.library.caltech.edu/records/gvmxc-w6g23", "eprint_id": 43528, "eprint_status": "archive", "datestamp": "2023-08-19 23:04:09", "lastmod": "2023-10-25 23:37:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Spurgeon-Joshua-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Velazquez-Jesus-M", "name": { "family": "Velazquez", "given": "Jesus M." }, "orcid": "0000-0003-2790-0976" }, { "id": "McDowell-Matthew-T", "name": { "family": "McDowell", "given": "Matthew T." }, "orcid": "0000-0001-5552-3456" } ] }, "title": "Improving O\u2082 production of WO\u2083 photoanodes with IrO\u2082 in acidic aqueous electrolyte", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2014 the Owner Societies.\n\nReceived 31 Dec 2013, Accepted 10 Jan 2014, First published online 10 Jan 2014.\n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. XPS data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology.\n\nPublished - c3cp55527e.pdf
Supplemental Material - c3cp55527e_si.pdf
", "abstract": "WO\u2083 is a promising candidate for a photoanode material in an acidic electrolyte, in which it is more stable than most metal oxides, but kinetic limitations combined with the large driving force available in the WO\u2083 valence band for water oxidation make competing reactions such as the oxidation of the acid counterion a more favorable reaction. The incorporation of an oxygen evolving catalyst (OEC) on the WO\u2083 surface can improve the kinetics for water oxidation and increase the branching ratio for O\u2082 production. Ir-based OECs were attached to WO\u2083 photoanodes by a variety of methods including sintering from metal salts, sputtering, drop-casting of particles, and electrodeposition to analyze how attachment strategies can affect photoelectrochemical oxygen production at WO\u2083 photoanodes in 1 M H\u2082SO\u2084. High surface coverage of catalyst on the semiconductor was necessary to ensure that most minority-carrier holes contributed to water oxidation through an active catalyst site rather than a side-reaction through the WO\u2083/electrolyte interface. Sputtering of IrO\u2082 layers on WO\u2083 did not detrimentally affect the energy-conversion behavior of the photoanode and improved the O\u2082 yield at 1.2 V vs. RHE from ~0% for bare WO\u2083 to 50\u201370% for a thin, optically transparent catalyst layer to nearly 100% for thick, opaque catalyst layers. Measurements with a fast one-electron redox couple indicated ohmic behavior at the IrO\u2082/WO\u2083 junction, which provided a shunt pathway for electrocatalytic IrO\u2082 behavior with the WO\u2083 photoanode under reverse bias. Although other OECs were tested, only IrO\u2082 displayed extended stability under the anodic operating conditions in acid as determined by XPS.", "date": "2014-01-10", "date_type": "published", "publication": "Physical Chemistry Chemical Physics", "volume": "16", "number": "8", "publisher": "Royal Society of Chemistry", "pagerange": "3623-3631", "id_number": "CaltechAUTHORS:20140128-073407483", "issn": "1463-9076", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140128-073407483", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c3cp55527e", "primary_object": { "basename": "c3cp55527e.pdf", "url": "https://authors.library.caltech.edu/records/gvmxc-w6g23/files/c3cp55527e.pdf" }, "related_objects": [ { "basename": "c3cp55527e_si.pdf", "url": "https://authors.library.caltech.edu/records/gvmxc-w6g23/files/c3cp55527e_si.pdf" } ], "pub_year": "2014", "author_list": "Spurgeon, Joshua M.; Velazquez, Jesus M.; et el." }, { "id": "https://authors.library.caltech.edu/records/7yt9f-1n253", "eprint_id": 46300, "eprint_status": "archive", "datestamp": "2023-08-22 11:24:40", "lastmod": "2023-10-26 19:39:18", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Haber-J-A", "name": { "family": "Haber", "given": "J. A." }, "orcid": "0000-0001-7847-5506" }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "S." }, "orcid": "0000-0001-8913-8505" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "C." }, "orcid": "0000-0002-1698-6754" }, { "id": "Suram-S-K", "name": { "family": "Suram", "given": "S." }, "orcid": "0000-0001-8170-2685" }, { "id": "Newhouse-P-F", "name": { "family": "Newhouse", "given": "P. F." }, "orcid": "0000-0003-2032-3010" }, { "id": "Soedarmadji-E", "name": { "family": "Soedarmadji", "given": "E." } }, { "id": "Marcin-M", "name": { "family": "Marcin", "given": "M." } }, { "id": "Kan-Kevin", "name": { "family": "Kan", "given": "K." } }, { "id": "Guevarra-D", "name": { "family": "Guevarra", "given": "D." }, "orcid": "0000-0002-9592-3195" }, { "id": "Jones-R", "name": { "family": "Jones", "given": "R." } }, { "id": "Becerra-N", "name": { "family": "Becerra", "given": "N." } }, { "id": "Cornell-E-W", "name": { "family": "Cornell", "given": "E. W." } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "J." } } ] }, "title": "Enabling Solar Fuels Technology With High Throughput Experimentation", "ispublished": "pub", "full_text_status": "public", "keywords": "combinatorial synthesis; photochemical; energy generation", "note": "\u00a9 2014 Materials Research Society.\n\nThis Material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy (Award No. DE-SC0004993). The authors thank the entire JCAP team for assistance with the design and implementation of the accelerated discovery pipeline.\n\nPublished - Gregoire_2014p1.pdf
", "abstract": "The High Throughput Experimentation (HTE) project of the Joint Center for Artificial Photosynthesis (JCAP, http://solarfuelshub.org/) performs accelerated discovery of new earth-abundant photoabsorbers and electrocatalysts. Through collaboration within the DOE solar fuels hub and with the broader research community, the new materials will be utilized in devices that efficiently convert solar energy, water and carbon dioxide into transportation fuels. JCAP-HTE builds high-throughput pipelines for the synthesis, screening and characterization of photoelectrochemical materials. In addition to a summary of these pipelines, we will describe several new screening instruments for high throughput (photo-)electrochemical measurements. These instruments are not only optimized for screening against solar fuels requirements, but also provide new tools for the broader combinatorial materials science community. We will also describe the high throughput discovery, follow-on verification, and device implementation of a new quaternary metal oxide catalyst. This rapid technology development from discovery to device implementation is a hallmark of the multi-faceted JCAP research effort.", "date": "2014-01-07", "date_type": "published", "publication": "MRS Proceedings", "volume": "1654", "publisher": "Materials Research Society", "pagerange": "Art. No. opl.2014.29", "id_number": "CaltechAUTHORS:20140617-094404706", "issn": "1946-4274", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140617-094404706", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1557/opl.2014.29", "primary_object": { "basename": "Gregoire_2014p1.pdf", "url": "https://authors.library.caltech.edu/records/7yt9f-1n253/files/Gregoire_2014p1.pdf" }, "pub_year": "2014", "author_list": "Gregoire, J. M.; Haber, J. A.; et el." }, { "id": "https://authors.library.caltech.edu/records/te0z2-nm976", "eprint_id": 43761, "eprint_status": "archive", "datestamp": "2023-08-19 22:53:09", "lastmod": "2023-10-20 22:57:02", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sanabria-Chinchilla-J", "name": { "family": "Sanabria-Chinchilla", "given": "Jean" } }, { "id": "Javier-A", "name": { "family": "Javier", "given": "Alnald" }, "orcid": "0000-0002-0306-5462" }, { "id": "Crouthers-D", "name": { "family": "Crouthers", "given": "Danielle" } }, { "id": "Baricuatro-J-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Darensbourg-M-Y", "name": { "family": "Darensbourg", "given": "Marcetta Y." } }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Immobilization-Enabled Proton Reduction Catalysis by a Di-iron Hydrogenase Mimic", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 Springer Science+Business Media New York. Published online: 17 September 2013. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The electrocatalysis work was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the synthesis and characterization of the di-iron complexes were supported by the National Science Foundation (CHE-0616695) (MYD) and the Texas A&M University-CONACYT program (MPS).", "abstract": "We have long been interested in the influence of surface immobilization on the electrochemical integrity of redox-active moieties [1\u20135]. Our studies have shown that, if the electroactive group itself is directly chemisorbed on (coordinated to) the electrode surface, profound alterations result in both the thermodynamics and kinetics of the electron transfer processes; the oxidative chemisorption of the iodide anion (to zerovalent iodine atoms) or the hydroquinone molecule (to benzoquinone) are prototypical examples. The changes are more subtle and less dramatic if the electroactive site is only a pendant moiety tethered to the surface via an anchor group; mercapto hydroquinone bound exclusively via the \u2013SH group is a well-known specimen. We recently extended our investigations to include enzyme-inspired molecular electrocatalysts in which the multinuclear reactive site may require a certain entatic state to carry out its catalytic function; the anticipation is that the motion-restricted surface-tethered species would suffer diminished catalytic activity. The results are described in this brief communication.", "date": "2014-01", "date_type": "published", "publication": "Electrocatalysis", "volume": "5", "number": "1", "publisher": "Springer", "pagerange": "5-7", "id_number": "CaltechAUTHORS:20140211-073815565", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140211-073815565", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF", "grant_number": "CHE-0616695" }, { "agency": "Texas A&M University-CONACYT Program" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-013-0157-y", "pub_year": "2014", "author_list": "Sanabria-Chinchilla, Jean; Javier, Alnald; et el." }, { "id": "https://authors.library.caltech.edu/records/hcg5e-jws83", "eprint_id": 43303, "eprint_status": "archive", "datestamp": "2023-08-19 22:30:50", "lastmod": "2023-10-25 23:26:45", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lichterman-Michael-Frankston-Yang", "name": { "family": "Lichterman", "given": "Michael F." }, "orcid": "0000-0002-0710-7068" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Handler-S-G", "name": { "family": "Handler", "given": "Sheila G." } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" } ] }, "title": "Enhanced Stability and Activity for Water Oxidation in Alkaline Media with Bismuth Vanadate Photoelectrodes Modified with a Cobalt Oxide Catalytic Layer Produced by Atomic Layer Deposition", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: October 16, 2013; Accepted: November 21, 2013; Published: November 21, 2013. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy under award DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub. XPS and AFM data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. We thank Dr. Ragip Pala for helpful discussions.\n\nSupplemental Material - jz4022415_si_001.pdf
", "abstract": "Atomic-layer deposition (ALD) of thin layers of cobalt oxide on n-type BiVO_4 produced photoanodes capable of water oxidation with essentially 100% faradaic efficiency in alkaline, pH = 13 electrolytes. By contrast, under the same operating conditions, BiVO_4 photoanodes without the Co oxide catalytic layer exhibited lower faradaic yields, of ca. 70%, for O_2 evolution and were unstable, becoming rapidly photopassivated. High numbers (>25) of ALD cycles of Co oxide deposition gave electrodes that displayed poor photoelectrochemical behavior, but 15\u201320 ALD cycles produced Co oxide overlayers ~1 nm in thickness, with the resulting photoelectrodes exhibiting a stable photocurrent density of 1.49 mA cm^(\u20132) at the oxygen-evolution potential and an open-circuit potential of 0.404 V versus the reversible hydrogen electrode, under 100 mW cm^(\u20132) of simulated air mass 1.5 illumination.", "date": "2013-12-05", "date_type": "published", "publication": "Journal of Physical Chemistry Letters", "volume": "4", "number": "23", "publisher": "American Chemical Society", "pagerange": "4188-4191", "id_number": "CaltechAUTHORS:20140110-084420760", "issn": "1948-7185", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140110-084420760", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jz4022415", "primary_object": { "basename": "jz4022415_si_001.pdf", "url": "https://authors.library.caltech.edu/records/hcg5e-jws83/files/jz4022415_si_001.pdf" }, "pub_year": "2013", "author_list": "Lichterman, Michael F.; Shaner, Matthew R.; et el." }, { "id": "https://authors.library.caltech.edu/records/jwtmz-ngq09", "eprint_id": 43166, "eprint_status": "archive", "datestamp": "2023-08-19 22:20:41", "lastmod": "2023-10-25 23:19:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haussener-S", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Simulations of the irradiation and temperature dependence of the efficiency of tandem photoelectrochemical water-splitting systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 The Royal Society of Chemistry. \n\nReceived 17th April 2013; Accepted 17th June 2013. First published online 17 Jun 2013.\n\nWe acknowledge the Joint Center for Artificial Photosynthesis, a\nDOE Energy Innovation Hub, supported through the Office of\nScience of the U.S. Department of Energy under Award Number\nDE-SC0004993. We thank Harry Atwater for fruitful discussions\non temperature-dependent analysis of realistic systems.\n\nPublished - c3ee41302k.pdf
Supplemental Material - c3ee41302k_si.pdf
", "abstract": "The instantaneous efficiency of an operating photoelectrochemical solar-fuel-generator system is a complicated function of the tradeoffs between the light intensity and temperature-dependence of the photovoltage and photocurrent, as well as the losses associated with factors that include ohmic resistances, concentration overpotentials, kinetic overpotentials, and mass transport. These tradeoffs were evaluated quantitatively using an advanced photoelectrochemical device model comprised of an analytical device physics model for the semiconducting light absorbers in combination with a multi-physics device model that solved for the governing conservation equations in the various other parts of the system. The model was used to evaluate the variation in system efficiency due to hourly and seasonal variations in solar irradiation as well as due to variation in the isothermal system temperature. The system performance characteristics were also evaluated as a function of the band gaps of the dual-absorber tandem component and its properties, as well as the device dimensions and the electrolyte conductivity. The modeling indicated that the system efficiency varied significantly during the day and over a year, exhibiting local minima at midday and a global minimum at midyear when the solar irradiation is most intense. These variations can be reduced by a favorable choice of the system dimensions, by a reduction in the electrolyte ohmic resistances, and/or by utilization of very active electrocatalysts for the fuel-producing reactions. An increase in the system temperature decreased the annual average efficiency and led to less rapid ramp-up and ramp-down phases of the system, but reduced midday and midyear instantaneous efficiency variations. Careful choice of the system dimensions resulted in minimal change in the system efficiency in response to degradation in the quality of the light absorbing materials. The daily and annually averaged mass of hydrogen production for the optimized integrated system compared favorably to the daily and annually averaged mass of hydrogen that was produced by an optimized stand-alone tandem photovoltaic array connected electrically to a stand-alone electrolyzer system. The model can be used to predict the performance of the system, to optimize the design of solar-driven water splitting devices, and to guide the development of components of the devices as well as of the system as a whole.", "date": "2013-12", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "6", "number": "12", "publisher": "Royal Society of Chemistry", "pagerange": "3605-3618", "id_number": "CaltechAUTHORS:20131224-102701042", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131224-102701042", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c3ee41302k", "primary_object": { "basename": "c3ee41302k.pdf", "url": "https://authors.library.caltech.edu/records/jwtmz-ngq09/files/c3ee41302k.pdf" }, "related_objects": [ { "basename": "c3ee41302k_si.pdf", "url": "https://authors.library.caltech.edu/records/jwtmz-ngq09/files/c3ee41302k_si.pdf" } ], "pub_year": "2013", "author_list": "Haussener, Sophia; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/smd5n-0aa45", "eprint_id": 43006, "eprint_status": "archive", "datestamp": "2023-08-19 22:15:01", "lastmod": "2023-10-25 23:12:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McCrory-C-C-L", "name": { "family": "McCrory", "given": "Charles C. L." }, "orcid": "0000-0001-9039-7192" }, { "id": "Jung-Suho", "name": { "family": "Jung", "given": "Suho" }, "orcid": "0000-0002-8119-3902" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" }, { "id": "Jaramillo-T-F", "name": { "family": "Jaramillo", "given": "Thomas F." }, "orcid": "0000-0001-9900-0622" } ] }, "title": "Benchmarking Heterogeneous Electrocatalysts for the Oxygen Evolution Reaction", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: July 11, 2013. Publication Date (Web): October 30, 2013. \n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy under award no. DE-SC0004993. We\nare grateful for the many useful insights we have received\nregarding this work from various members of the electrochemistry community. In particular, we would like to\nacknowledge useful discussions with Allen J. Bard, Fred C.\nAnson, Nathan S. Lewis, Carl A. Koval, Manuel P. Soriaga, and\nHans-Joachim Lewerenz. XPS data was collected at the\nMolecular Materials Research Center of the Beckman Institute\nof the California Institute of Technology. The authors declare no competing financial interest.\n\nSupplemental Material - ja407115p_si_001.pdf
", "abstract": "Objective evaluation of the activity of electrocatalysts for water oxidation is of fundamental importance for the development of promising energy conversion technologies including integrated solar water-splitting devices, water electrolyzers, and Li-air batteries. However, current methods employed to evaluate oxygen-evolving catalysts are not standardized, making it difficult to compare the activity and stability of these materials. We report a protocol for evaluating the activity, stability, and Faradaic efficiency of electrodeposited oxygen-evolving electrocatalysts. In particular, we focus on methods for determining electrochemically active surface area and measuring electrocatalytic activity and stability under conditions relevant to an integrated solar water-splitting device. Our primary figure of merit is the overpotential required to achieve a current density of 10 mA cm^(\u20132) per geometric area, approximately the current density expected for a 10% efficient solar-to-fuels conversion device. Utilizing the aforementioned surface area measurements, one can determine electrocatalyst turnover frequencies. The reported protocol was used to examine the oxygen-evolution activity of the following systems in acidic and alkaline solutions: CoO_x, CoPi, CoFeO_x, NiO_x, NiCeO_x, NiCoO_x, NiCuO_x, NiFeO_x, and NiLaO_x. The oxygen-evolving activity of an electrodeposited IrO_x catalyst was also investigated for comparison. Two general observations are made from comparing the catalytic performance of the OER catalysts investigated: (1) in alkaline solution, every non-noble metal system achieved 10 mA cm^(\u20132) current densities at similar operating overpotentials between 0.35 and 0.43 V, and (2) every system but IrO_x was unstable under oxidative conditions in acidic solutions.", "date": "2013-11-13", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "45", "publisher": "American Chemical Society", "pagerange": "16977-16987", "id_number": "CaltechAUTHORS:20131213-151603830", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131213-151603830", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ja407115p", "primary_object": { "basename": "ja407115p_si_001.pdf", "url": "https://authors.library.caltech.edu/records/smd5n-0aa45/files/ja407115p_si_001.pdf" }, "pub_year": "2013", "author_list": "McCrory, Charles C. L.; Jung, Suho; et el." }, { "id": "https://authors.library.caltech.edu/records/dfart-png72", "eprint_id": 42256, "eprint_status": "archive", "datestamp": "2023-08-19 21:56:23", "lastmod": "2023-10-25 15:47:22", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lin-Tzu-Pin", "name": { "family": "Lin", "given": "Tzu-Pin" }, "orcid": "0000-0001-7041-7213" }, { "id": "Peters-J-C", "name": { "family": "Peters", "given": "Jonas C." }, "orcid": "0000-0002-6610-4414" } ] }, "title": "Boryl-Mediated Reversible H_2 Activation at Cobalt: Catalytic Hydrogenation, Dehydrogenation, and Transfer Hydrogenation", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society. \n\nPublication Date (Web): September 30, 2013. Received: August 13, 2013. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja408397v_si_001.pdf
Supplemental Material - ja408397v_si_002.cif
", "abstract": "We describe the synthesis of a cobalt(I)\u2013N2 complex (2) supported by a meridional bis-phosphino-boryl (PBP) ligand. Complex 2 undergoes a clean reaction with 2 equiv of dihydrogen to afford a dihydridoboratocobalt dihydride (3). The ability of boron to switch between a boryl and a dihydridoborate conformation makes possible the reversible conversion of 2 and 3. Complex 3 reacts with HMe_2N\u2013BH_3 to give a hydridoborane cobalt tetrahydridoborate complex. We explore this boryl\u2013cobalt system in the context of catalytic olefin hydrogenation as well as amine\u2013borane dehydrogenation/transfer hydrogenation.", "date": "2013-10-16", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "41", "publisher": "American Chemical Society", "pagerange": "15310-15313", "id_number": "CaltechAUTHORS:20131105-144406165", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131105-144406165", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ja408397v", "primary_object": { "basename": "ja408397v_si_001.pdf", "url": "https://authors.library.caltech.edu/records/dfart-png72/files/ja408397v_si_001.pdf" }, "related_objects": [ { "basename": "ja408397v_si_002.cif", "url": "https://authors.library.caltech.edu/records/dfart-png72/files/ja408397v_si_002.cif" } ], "pub_year": "2013", "author_list": "Lin, Tzu-Pin and Peters, Jonas C." }, { "id": "https://authors.library.caltech.edu/records/bjsh3-bdz24", "eprint_id": 42219, "eprint_status": "archive", "datestamp": "2023-08-19 21:51:00", "lastmod": "2023-10-25 15:45:28", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "May-M-M", "name": { "family": "May", "given": "Matthias M." }, "orcid": "0000-0002-1252-806X" }, { "id": "Supplie-O", "name": { "family": "Supplie", "given": "Oliver" }, "orcid": "0000-0002-2424-7118" }, { "id": "H\u00f6hn-C", "name": { "family": "H\u00f6hn", "given": "Christian" }, "orcid": "0000-0002-2043-598X" }, { "id": "van-de-Krol-R", "name": { "family": "van de Krol", "given": "Roel" }, "orcid": "0000-0003-4399-399X" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" }, { "id": "Hannappel-T", "name": { "family": "Hannappel", "given": "Thomas" }, "orcid": "0000-0002-6307-9831" } ] }, "title": "The interface of GaP(100) and H_2O studied by photoemission and reflection anisotropy spectroscopy", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Institute of Physics. Received 22 May 2013. Published 7 October 2013. The authors thank Abdelkrim Chemseddine for valuable discussions and Wolf-Dietrich Zabka for experimental assistance. MMM acknowledges a scholarship from Studienstiftung des deutschen Volkes. Part of this work was supported by the German Research Foundation (DFG, project no. HA 3096/4).\n\nPublished - 1367-2630_15_10_103003.pdf
Submitted - 1305.5815v2.pdf
", "abstract": "We study the initial interaction of adsorbed H_2O with P-rich and Ga-rich GaP(100) surfaces. Atomically well defined surfaces are prepared by metal-organic vapour phase epitaxy and transferred contamination-free to ultra-high vacuum, where water is adsorbed at room temperature. Finally, the surfaces are annealed in vapour phase ambient. During all steps, the impact on the surface properties is monitored with in situ reflection anisotropy spectroscopy (RAS). Photoelectron spectroscopy and low-energy electron diffraction are applied for further in system studies. After exposure up to saturation of the RA spectra, the Ga-rich (2 \u00d7 4) surface reconstruction exhibits a sub-monolayer coverage in form of a mixture of molecularly and dissociatively adsorbed water. For the p(2 \u00d7 2)/c(4 \u00d7 2) P-rich surface reconstruction, a new c(2 \u00d7 2) superstructure forms upon adsorption and the uptake of adsorbate is significantly reduced when compared to the Ga-rich surface. Our findings show that microscopic surface reconstructions of GaP(100) greatly impact the mechanism of initial interface formation with water, which could benefit the design of e.g. photoelectrochemical water splitting devices.", "date": "2013-10-07", "date_type": "published", "publication": "New Journal of Physics", "volume": "15", "number": "10", "publisher": "IOP", "pagerange": "Art. No. 103003", "id_number": "CaltechAUTHORS:20131104-105944560", "issn": "1367-2630", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131104-105944560", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Studienstiftung des deutschen Volkes" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "HA 3096/4" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1088/1367-2630/15/10/103003", "primary_object": { "basename": "1305.5815v2.pdf", "url": "https://authors.library.caltech.edu/records/bjsh3-bdz24/files/1305.5815v2.pdf" }, "related_objects": [ { "basename": "1367-2630_15_10_103003.pdf", "url": "https://authors.library.caltech.edu/records/bjsh3-bdz24/files/1367-2630_15_10_103003.pdf" } ], "pub_year": "2013", "author_list": "May, Matthias M.; Supplie, Oliver; et el." }, { "id": "https://authors.library.caltech.edu/records/j3j2v-49s47", "eprint_id": 42538, "eprint_status": "archive", "datestamp": "2023-08-19 21:39:10", "lastmod": "2023-10-25 16:45:26", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Haussener-S", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Berger-A-D", "name": { "family": "Berger", "given": "Alan D." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "An analysis of the optimal band gaps of light absorbers in integrated tandem photoelectrochemical water-splitting systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 Royal Society of Chemistry. \n\nReceived 7th February 2013; Accepted 11th April 2013; Published online 10th May 2013. \n\nThis work was supported through the Office of Science of the U.S. Department of Energy under Award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub.\n\nPublished - c3ee40453f.pdf
Supplemental Material - c3ee40453f_si.pdf
", "abstract": "The solar-to-hydrogen (STH) efficiency limits, along with the maximum efficiency values and the corresponding optimal band gap combinations, have been evaluated for various combinations of light absorbers arranged in a tandem configuration in realistic, operational water-splitting prototypes. To perform the evaluation, a current\u2013voltage model was employed, with the light absorbers, electrocatalysts, solution electrolyte, and membranes coupled in series, and with the directions of optical absorption, carrier transport, electron transfer and ionic transport in parallel. The current density vs. voltage characteristics of the light absorbers were determined by detailed-balance calculations that accounted for the Shockley\u2013Queisser limit on the photovoltage of each absorber. The maximum STH efficiency for an integrated photoelectrochemical system was found to be ~31.1% at 1 Sun (=1 kW m\u207b\u00b2, air mass 1.5), fundamentally limited by a matching photocurrent density of 25.3 mA cm\u207b\u00b2 produced by the light absorbers. Choices of electrocatalysts, as well as the fill factors of the light absorbers and the Ohmic resistance of the solution electrolyte also play key roles in determining the maximum STH efficiency and the corresponding optimal tandem band gap combination. Pairing 1.6\u20131.8 eV band gap semiconductors with Si in a tandem structure produces promising light absorbers for water splitting, with theoretical STH efficiency limits of >25%.", "date": "2013-10", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "6", "number": "10", "publisher": "Royal Society of Chemistry", "pagerange": "2984-2993", "id_number": "CaltechAUTHORS:20131118-152050309", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131118-152050309", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c3ee40453f", "primary_object": { "basename": "c3ee40453f.pdf", "url": "https://authors.library.caltech.edu/records/j3j2v-49s47/files/c3ee40453f.pdf" }, "related_objects": [ { "basename": "c3ee40453f_si.pdf", "url": "https://authors.library.caltech.edu/records/j3j2v-49s47/files/c3ee40453f_si.pdf" } ], "pub_year": "2013", "author_list": "Hu, Shu; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/0gejy-m5733", "eprint_id": 42318, "eprint_status": "archive", "datestamp": "2023-08-19 21:34:56", "lastmod": "2023-10-25 15:49:53", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew R." }, "orcid": "0000-0003-4682-9757" }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Current-voltage characteristics of coupled photodiode-electrocatalyst devices", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Institute of Physics Publishing LLC. Received 25 February 2013; accepted 10 September 2013; published online 3 October 2013. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award No. DESC0004993. K.F. is supported by the National Science\nFoundation Graduate Research Fellowship under Grant No.\nDGE-1144469. M.S. acknowledges the support of the Resnick\nSustainability Institute. The authors would like to thank Dr.\nNathan S. Lewis and Dr. Harry A. Atwater for advising during\nthis project and Dr. Shane Ardo for helpful discussions.\n\nPublished - 1.4822179.pdf
", "abstract": "Analytical expressions for the illuminated current-voltage characteristics of coupled photodiode-electrocatalyst fuel forming devices are derived. The approach is based on combining solid-state diode behavior with metal electrochemistry via the diode equation and the Butler-Volmer equation (charge transfer coefficients: \u03b1_A\u2009=\u2009\u03b1_C\u2009=\u2009\u03b1) or the Tafel equation ( |\u03b7|\u2265^(118mV)_(ne)), respectively. The analytical expression for the current-voltage behavior of the coupled photodiode-electrocatalyst device (\u03b1_A\u2009=\u2009\u03b1_C\u2009=\u20090.5) and an isolated photodiode is plotted, compared, and augmented with band diagrams at equilibrium, open circuit, short circuit, and the maximum power point to illustrate the effect of coupling an electrocatalyst to a photodiode. The applicability of the derived equations is then demonstrated by comparing with a recently reported high efficiency, thin film InP/InO_xP_y/Rh photoelectrosynthetic hydrogen evolution device.", "date": "2013-09-30", "date_type": "published", "publication": "Applied Physics Letters", "volume": "103", "number": "14", "publisher": "American Institute of Physics", "pagerange": "Art. No. 143905", "id_number": "CaltechAUTHORS:20131107-150452899", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20131107-150452899", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" }, { "agency": "Resnick Sustainability Institute" } ] }, "local_group": { "items": [ { "id": "Resnick-Sustainability-Institute" }, { "id": "JCAP" } ] }, "doi": "10.1063/1.4822179", "primary_object": { "basename": "1.4822179.pdf", "url": "https://authors.library.caltech.edu/records/0gejy-m5733/files/1.4822179.pdf" }, "pub_year": "2013", "author_list": "Shaner, Matthew R.; Fountaine, Katherine T.; et el." }, { "id": "https://authors.library.caltech.edu/records/67szj-e5a08", "eprint_id": 120624, "eprint_status": "archive", "datestamp": "2023-08-22 10:09:33", "lastmod": "2023-10-18 17:55:42", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haussener-Sophia", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Weber-Adam-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Simulations of the Irradiation and Temperature Dependence of the Efficiency of Tandem Photoelectrochemical Water-splitting Systems", "ispublished": "pub", "full_text_status": "public", "keywords": "General Medicine", "note": "We acknowledge the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. We thank Harry Atwater for fruitful discussions on temperature-dependent analysis of realistic systems.", "abstract": "The efficiency of an operating photoelectrochemical solar-fuels-generator system is determined by the system design, the properties and morphology of the system's components, and the operational conditions. We used a previously developed model comprising of i) the detailed balance limit to describe the currentpotential performance of the photoabsorber component, and ii) the detailed multi-physics device model solving for the governing conservation equations (mass, momentum, species and charge) spatially resolved in the device, to quantify the performance of photoelectrochemical devices. The investigated the performance and its variations as a function of operational conditions, i.e. daily and seasonal irradiation variations, concentration factor of irradiation, and isothermal device temperature. Additionally, the difference in performance of an integrated photoelectrochemical system and a photovoltaic array connected electrically to a standalone electrolyzer system was quantified.", "date": "2013-08-31", "date_type": "published", "publication": "ECS Transactions", "volume": "58", "number": "2", "publisher": "Electrochemical Society", "pagerange": "293-303", "id_number": "CaltechAUTHORS:20230329-637828000.2", "issn": "1938-5862", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20230329-637828000.2", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/05802.0293ecst", "pub_year": "2013", "author_list": "Haussener, Sophia; Hu, Shu; et el." }, { "id": "https://authors.library.caltech.edu/records/8e0wb-t9r29", "eprint_id": 41137, "eprint_status": "archive", "datestamp": "2023-08-19 21:05:53", "lastmod": "2023-10-24 23:28:47", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Letilly-M", "name": { "family": "Letilly", "given": "Marika" } }, { "id": "Skorupska-K", "name": { "family": "Skorupska", "given": "Katarzyna" } }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "Hans-Joachim" }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Initial Phase of Photoelectrochemical Conditioning of Silicon in Alkaline Media: Surface Chemistry and Topography", "ispublished": "pub", "full_text_status": "restricted", "note": "\u00a9 2013 American Chemical Society.\n\nReceived: February 22, 2013;\nRevised: July 7, 2013;\nPublished: July 16, 2013.\n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, as follows: Part of the electrochemical experiments were\nsupported though the Office of Science of the U.S. Department\nof Energy under Award No. DE-SC0004993; the SRPES and\nERDA measurements and the AFM and TEM images were\nsupported by the Deutsche Forschungsgemeinschaft-DFG\nunder Award No. LE 1192/4-1/2. The authors are grateful to\nM. Kanis and H. Jungblut for contributing to the SRPES\nexperiments, to M. Aggour for his help regarding electrochemical\nmeasurements, to U. Bloeck for recording of the TEM\nimages, and to F. Munnik and K. Saravanan for performing the ERDA measurements. M.L. is grateful for financial support of\nthe DFG (Award No. LE 1192/4-1/2).", "abstract": "Oxidation and dissolution phenomena of Si(111) in alkaline electrolyte are investigated by a combination of photoelectrochemistry, scanning probe microscopy (SPM), transmission electron microscopy (TEM) and in-system synchrotron radiation photoelectron spectroscopy (SRPES). The surface topography in the initial anodic potential regime shows the formation of mesoscale pores with widths in the range 300\u2013500 nm and partial surface oxidation. The surface chemistry assessment by SRPES shows patchy silicon oxide growth, suboxides, and remnants of the former hydrogen terminated surface areas. The use of the obtained self-organized nanostructures for application in nanoemitter photocatalytic solar cells is discussed. The necessary requirements regarding the total surface area of electrocatalysts needed to sustain the current density due to light-induced excess minority carriers in conjunction with the exchange current density of the considered heterogeneous catalysts is discussed.", "date": "2013-08-15", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "117", "number": "32", "publisher": "American Chemical Society", "pagerange": "16381-16391", "id_number": "CaltechAUTHORS:20130906-091022940", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130906-091022940", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LE 1192/4-1/2" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp401853p", "pub_year": "2013", "author_list": "Letilly, Marika; Skorupska, Katarzyna; et el." }, { "id": "https://authors.library.caltech.edu/records/12akh-8sd35", "eprint_id": 41039, "eprint_status": "archive", "datestamp": "2023-08-19 20:30:30", "lastmod": "2023-10-24 23:24:29", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiao-Kechao", "name": { "family": "Xiao", "given": "Kechao" } }, { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "McCluskey-P-J", "name": { "family": "McCluskey", "given": "Patrick J." } }, { "id": "Dale-Darren", "name": { "family": "Dale", "given": "Darren" } }, { "id": "Vlassak-J-J", "name": { "family": "Vlassak", "given": "Joost J." } } ] }, "title": "Scanning AC nanocalorimetry combined with in-situ x-ray diffraction", "ispublished": "pub", "full_text_status": "public", "keywords": "bismuth, calorimetry, cooling, indium, melting, metallic thin films, nanosensors, solidification, tin, X-ray diffraction", "note": "\u00a9 2013 AIP Publishing LLC.\n\nReceived 23 April 2013; accepted 6 June 2013; published online 24 June 2013.\n\nThe authors thank Aaron Lyndaker for assistance with\nthe synchrotron experiments and James MacArthur for assistance\nwith the custom electronics. The work presented in this\npaper was supported by the Air Force Office of Scientific\nResearch under Grant Nos. FA9550-08-1-0374 and FA9550-12-1-0098 and by the Materials Research Science and\nEngineering Center at Harvard University (NSF-DMR-0820484). The measurements were performed at the Cornell\nHigh Energy Synchrotron source (CHESS), which is supported\nby the National Science Foundation and the National\nInstitutes of Health/National Institute of General Medical\nSciences under NSF Award No. DMR-0936384. The sensors\nwere fabricated at the Center for Nanoscale Systems, a member\nof the National Nanotechnology Infrastructure Network,\nwhich is supported by the National Science Foundation\nunder NSF Award No. ECS-0335765. The Center for\nNanoscale Systems is part of the Faculty of Arts and\nSciences at Harvard University.\n\nPublished - JApplPhys_113_243501.pdf
", "abstract": "Micromachined nanocalorimetry sensors have shown excellent performance for high-temperature and high-scanning rate calorimetry measurements. Here, we combine scanning AC nanocalorimetry with in-situ x-ray diffraction (XRD) to facilitate interpretation of the calorimetry measurements. Time-resolved XRD during in-situ operation of nanocalorimetry sensors using intense, high-energy synchrotron radiation allows unprecedented characterization of thermal and structural material properties. We demonstrate this experiment with detailed characterization of the melting and solidification of elemental Bi, In, and Sn thin-film samples, using heating and cooling rates up to 300\u2009K/s. Our experiments show that the solidification process is distinctly different for each of the three samples. The experiments are performed using a combinatorial device that contains an array of individually addressable nanocalorimetry sensors. Combined with XRD, this device creates a new platform for high-throughput mapping of the composition dependence of solid-state reactions and phase transformations.", "date": "2013-06-28", "date_type": "published", "publication": "Journal of Applied Physics", "volume": "113", "number": "24", "publisher": "American Institute of Physics", "pagerange": "Art. No. 243501", "id_number": "CaltechAUTHORS:20130830-140035652", "issn": "0021-8979", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130830-140035652", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-08-1-0374" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0098" }, { "agency": "NSF", "grant_number": "DMR-0820484" }, { "agency": "NIH" }, { "agency": "NSF", "grant_number": "DMR-0936384" }, { "agency": "NSF", "grant_number": "ECS-0335765" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4811686", "pmcid": "PMC3676369", "primary_object": { "basename": "JApplPhys_113_243501.pdf", "url": "https://authors.library.caltech.edu/records/12akh-8sd35/files/JApplPhys_113_243501.pdf" }, "pub_year": "2013", "author_list": "Xiao, Kechao; Gregoire, John M.; et el." }, { "id": "https://authors.library.caltech.edu/records/j997w-2d154", "eprint_id": 46140, "eprint_status": "archive", "datestamp": "2023-08-19 20:28:11", "lastmod": "2023-10-26 18:42:56", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "C." }, "orcid": "0000-0002-1698-6754" }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "S." }, "orcid": "0000-0001-8913-8505" }, { "id": "Liu-Xiaonao", "name": { "family": "Liu", "given": "X." } }, { "id": "Marcin-M-R", "name": { "family": "Marcin", "given": "M." } }, { "id": "Cornell-E-W", "name": { "family": "Cornell", "given": "E. W." } }, { "id": "Fan-J", "name": { "family": "Fan", "given": "J." } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } } ] }, "title": "Combined Catalysis and Optical Screening for High Throughput Discovery of Solar Fuels Catalysts", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 The Electrochemical Society. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The experiments and data interpretation were supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; J.F. acknowledges financial support from the National Science Foundation of China (21003106 and 20873122). The authors thank Mr. Lung-Sheng Lin for assistance in fabrication of the cell and Mr. William Fisher of Lawrence Berkeley National Laboratory for assistance in fabrication of the capillary for the reference electrode. The authors also thank Drs. Joel Haber, Eric McFarland, Nathan Lewis, Carl Koval and Joachim Lewerenz for helpful discussions.\n\nPublished - Gregoire_2013p9.pdf
", "abstract": "Considerable research and development efforts are being devoted to the efficient generation of solar fuels. A solar fuels device couples a solar photoabsorber with catalysts to convert solar energy to chemical energy via reactions such as oxygen evolution (water splitting). Widespread deployment of this technology hinges upon discovery of new materials through efforts such as the high throughput screening of oxygen evolution catalysts, as discussed in this manuscript. We derive an expression for the efficiency of the oxygen evolution catalyst that combines catalytic and optical properties. Using this hybrid efficiency, we screen 5456 samples in a (Fe-Co-Ni-Ti)O_x pseudo-quaternary catalyst library using automated, high throughput electrochemistry and optical experiments. The observed compositional trends in this catalyst efficiency lead to the discovery of a new high performance composition region.", "date": "2013-06-20", "date_type": "published", "publication": "ECS Transactions", "volume": "50", "number": "49", "publisher": "Electrochemical Society", "pagerange": "9-20", "id_number": "CaltechAUTHORS:20140609-083826658", "issn": "1938-5862", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140609-083826658", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "National Science Foundation of China", "grant_number": "21003106" }, { "agency": "National Science Foundation of China", "grant_number": "20873122" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/05049.0009ecst", "primary_object": { "basename": "Gregoire_2013p9.pdf", "url": "https://authors.library.caltech.edu/records/j997w-2d154/files/Gregoire_2013p9.pdf" }, "pub_year": "2013", "author_list": "Gregoire, J. M.; Xiang, C.; et el." }, { "id": "https://authors.library.caltech.edu/records/f9dcz-xm731", "eprint_id": 39416, "eprint_status": "archive", "datestamp": "2023-08-19 20:08:05", "lastmod": "2023-10-24 16:47:41", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Chi-Chun-Yung", "name": { "family": "Chi", "given": "Chun-Yung" } }, { "id": "Fountaine-K-T", "name": { "family": "Fountaine", "given": "Katherine T." }, "orcid": "0000-0002-0414-8227" }, { "id": "Yao-Maoqing", "name": { "family": "Yao", "given": "Maoqing" } }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" }, { "id": "Dapkus-P-D", "name": { "family": "Dapkus", "given": "P. Daniel" } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Zhou-Chongwu", "name": { "family": "Zhou", "given": "Chongwu" }, "orcid": "0000-0001-8448-8450" } ] }, "title": "Optical, electrical, and solar energy-conversion properties of gallium arsenide nanowire-array photoanodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 The Royal Society of Chemistry. \n\nReceived 23rd January 2013; Accepted 14th March 2013. First published online 17 Apr 2013. \n\nThe non-aqueous photoelectrochemistry and optical simulation\nwas supported by the Office of Science of the U.S. Department of Energy under Award no. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub; and the MOCVD growth was supported by the Center for Energy Nanoscience, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Basic Energy Sciences under Award Number DE-SC0001013. The authors acknowledge Professor Hans-Joachim Lewerenz, Professor Michelle Povinelli and Stanley Burgos for helpful discussions, and Dr Ron Grimm for assistance with the photoelectrochemical studies. Optical data were collected at the Molecular Materials Research Center of the Beckman Institute of the California Institute of Technology. M.Y. acknowledges a USC Provost's Ph.D. Fellowship and K. T. F. acknowledges the National Science Foundation for Graduate Research Fellowship under Grant no. DGE-1144469.\n\nSupplemental Material - c3ee40243f.pdf
", "abstract": "Periodic arrays of n-GaAs nanowires have been grown by selective-area metal\u2013organic chemical-vapor deposition on Si and GaAs substrates. The optical absorption characteristics of the nanowire-arrays were investigated experimentally and theoretically, and the photoelectrochemical energy-conversion properties of GaAs nanowire arrays were evaluated in contact with one-electron, reversible, redox species in non-aqueous solvents. The radial semiconductor/liquid junction in the nanowires produced near-unity external carrier-collection efficiencies for nanowire-array photoanodes in contact with non-aqueous electrolytes. These anodes exhibited overall inherent photoelectrode energy-conversion efficiencies of [similar]8.1% under 100 mW cm^\u22122 simulated Air Mass 1.5 illumination, with open-circuit photovoltages of 590 \u00b1 15 mV and short-circuit current densities of 24.6 \u00b1 2.0 mA cm^\u22122. The high optical absorption, and minimal reflection, at both normal and off-normal incidence of the GaAs nanowire arrays that occupy <5% of the fractional area of the electrode can be attributed to efficient incoupling into radial nanowire guided and leaky waveguide modes.", "date": "2013-06", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "6", "number": "6", "publisher": "Royal Society of Chemistry", "pagerange": "1879-1890", "id_number": "CaltechAUTHORS:20130717-111233079", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130717-111233079", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001013" }, { "agency": "University of Southern California" }, { "agency": "NSF Graduate Research Fellowship", "grant_number": "DGE-1144469" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c3ee40243f", "primary_object": { "basename": "c3ee40243f.pdf", "url": "https://authors.library.caltech.edu/records/f9dcz-xm731/files/c3ee40243f.pdf" }, "pub_year": "2013", "author_list": "Hu, Shu; Chi, Chun-Yung; et el." }, { "id": "https://authors.library.caltech.edu/records/jgq7q-pb495", "eprint_id": 40719, "eprint_status": "archive", "datestamp": "2023-08-19 20:10:34", "lastmod": "2023-10-24 17:20:48", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Chi-Chun-Yung", "name": { "family": "Chi", "given": "Chun-Yung" } }, { "id": "Chang-Chia-Chi", "name": { "family": "Chang", "given": "Chia-Chi" } }, { "id": "Hu-Shu", "name": { "family": "Hu", "given": "Shu" }, "orcid": "0000-0002-5041-0169" }, { "id": "Yeh-Ting-Wei", "name": { "family": "Yeh", "given": "Ting-Wei" } }, { "id": "Cronin-S-B", "name": { "family": "Cronin", "given": "Stephen B." } }, { "id": "Dapkus-P-D", "name": { "family": "Dapkus", "given": "P. Daniel" } } ] }, "title": "Twin-Free GaAs Nanosheets by Selective Area Growth: Implications for Defect-Free Nanostructures", "ispublished": "pub", "full_text_status": "public", "keywords": "GaAs, nanosheet, defect-free, twin-free, selective-area-growth, MOCVD", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: February 12, 2013; Revised: April 17, 2013; Published: May 1, 2013. \n\nThis work was supported by the Center for Energy Nanoscience (CEN), an Energy Frontier Research Center (EFRC) funded by the U.S. Department of Energy, Office of Science and Office of Basic Energy Sciences, under Award Number DE-SC0001013. S.H. would like to acknowledge the funding supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993 to the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub.\n\nSupplemental Material - nl400561j_si_002.pdf
", "abstract": "Highly perfect, twin-free GaAs nanosheets grown on (111)B surfaces by selective area growth (SAG) are demonstrated. In contrast to GaAs nanowires grown by (SAG) in which rotational twins and stacking faults are almost universally observed, twin formation is either suppressed or eliminated within properly oriented nanosheets are grown under a range of growth conditions. A morphology transition in the nanosheets due to twinning results in surface energy reduction, which may also explain the high twin-defect density that occurs within some III\u2013V semiconductor nanostructures, such as GaAs nanowires. Calculations suggest that the surface energy is significantly reduced by the formation of {111}-plane bounded tetrahedra after the morphology transition of nanowire structures. By contrast, owing to the formation of two vertical {11\u03050} planes which comprise the majority of the total surface energy of nanosheet structures, the energy reduction effect due to the morphology transition is not as dramatic as that for nanowire structures. Furthermore, the surface energy reduction effect is mitigated in longer nanosheets which, in turn, suppresses twinning.", "date": "2013-06", "date_type": "published", "publication": "Nano Letters", "volume": "13", "number": "6", "publisher": "American Chemical Society", "pagerange": "2506-2515", "id_number": "CaltechAUTHORS:20130819-091048166", "issn": "1530-6984", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130819-091048166", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0001013" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/nl400561j", "primary_object": { "basename": "nl400561j_si_002.pdf", "url": "https://authors.library.caltech.edu/records/jgq7q-pb495/files/nl400561j_si_002.pdf" }, "pub_year": "2013", "author_list": "Chi, Chun-Yung; Chang, Chia-Chi; et el." }, { "id": "https://authors.library.caltech.edu/records/vywhf-9h936", "eprint_id": 38829, "eprint_status": "archive", "datestamp": "2023-08-22 09:26:38", "lastmod": "2023-10-23 23:31:13", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Sanabria-Chinchilla-J", "name": { "family": "Sanabria-Chinchilla", "given": "Jean" } }, { "id": "Chen-Xiaole", "name": { "family": "Chen", "given": "Xiaole" } }, { "id": "Li-Ding", "name": { "family": "Li", "given": "Ding" } }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "Chemisorption-Isotherm Measurements at Electrode Surfaces by Quantitative High-Resolution Electron Energy Loss Spectroscopy", "ispublished": "pub", "full_text_status": "restricted", "keywords": "High-resolution electron energy loss spectroscopy; Chemisorption isotherms; Surface coverage measurements by HREELS; Background-intensity normalization of HREEL spectra; HREELS of benzoquinone chemisorbed on Pd(100) electrodes", "note": "\u00a9 2013 Springer Science+Business Media New York.\nPublished online: 31 January 2013.\nThis material is based upon work performed by\nthe Joint Center for Artificial Photosynthesis, a DOE Energy Innovation\nHub, as follows: The HREELS spectral analysis and surface-coverage\ndetermination were supported through the Office of Science\nof the US Department of Energy under award no. DE-SC0004993; the\nTLE and HREELS experimental measurements were supported by The\nWelch Foundation (A-1064).", "abstract": "The chemisorption isotherm of benzoquinone at a well-defined Pd(100) surface was obtained by quantitative high-resolution electron energy loss spectroscopy (HREELS). Extraction of surface-coverage information from HREELS required the normalization of integrated peak intensities to compensate for differences in the backscattered electron flux brought about by the organic adlayer. A common procedure rests on a match of the elastic-peak heights, but it fails for organic adsorbates since those introduce surface roughness that result in a higher stream of inelastically scattered electrons. A more accurate method is based on the equalization of the incident electron beam currents. This is attained only when the background intensities integrated over a peak-free spectral region are set equal to one another. The HREELS-generated isotherm was compared with that acquired by thin-layer electrochemical measurements; excellent agreement was observed.", "date": "2013-06", "date_type": "published", "publication": "Electrocatalysis", "volume": "4", "number": "2", "publisher": "Springer", "pagerange": "101-103", "id_number": "CaltechAUTHORS:20130606-094123039", "issn": "1868-2529", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130606-094123039", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Robert A. Welch Foundation", "grant_number": "A-1064" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1007/s12678-013-0125-6", "pub_year": "2013", "author_list": "Sanabria-Chinchilla, Jean; Chen, Xiaole; et el." }, { "id": "https://authors.library.caltech.edu/records/33w9f-1sd55", "eprint_id": 39898, "eprint_status": "archive", "datestamp": "2023-08-19 19:58:14", "lastmod": "2023-10-24 17:17:52", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Xiao-Kechao", "name": { "family": "Xiao", "given": "Kechao" } }, { "id": "McCluskey-P-J", "name": { "family": "McCluskey", "given": "Patrick J." } }, { "id": "Dale-Darren", "name": { "family": "Dale", "given": "Darren" } }, { "id": "Cuddalorepatta-G", "name": { "family": "Cuddalorepatta", "given": "Gayatri" } }, { "id": "Vlassak-J-J", "name": { "family": "Vlassak", "given": "Joost J." } } ] }, "title": "In-situ X-ray diffraction combined with scanning AC nanocalorimetry applied to a Fe_(0.84)Ni_(0.16) thin-film sample", "ispublished": "pub", "full_text_status": "public", "keywords": "calorimetry, cooling, heat treatment, heating, iron alloys, martensitic transformations, metallic thin films, nickel alloys, synchrotron radiation, X-ray diffraction", "note": "\u00a9 2013 AIP Publishing LLC.\n\nReceived 4 April 2013; accepted 2 May 2013; published online 21 May 2013.\n\nThe authors thank Aaron Lyndaker for assistance with the\nsynchrotron experiments and James MacArthur for assistance\nwith the custom electronics. This work was supported by the\nMaterials Research Science and Engineering Center at Harvard\nUniversity (NSF-DMR-0820484), the Air Force Office of\nScientific Research (FA9550-12-1-0098), and the DOE Office\nof Basics Energy Sciences (DE-SC-0004889). The experiments\nwere conducted at CHESS, which is supported by the NSF &\nNIH/NIGMS via NSF Award No. DMR-0936384. Device fabrication\nwas supported by the Center for Nanoscale Systems at\nHarvard University (NSF-ECS-0335765).\n\nPublished - ApplPhysLett_102_201902.pdf
", "abstract": "We combine the characterization techniques of scanning AC nanocalorimetry and x-ray diffraction to study phase transformations in complex materials system. Micromachined nanocalorimeters have excellent performance for high-temperature and high-scanning-rate calorimetry measurements. Time-resolved X-ray diffraction measurements during in-situ operation of these devices using synchrotron radiation provide unprecedented characterization of thermal and structural material properties. We apply this technique to a Fe_(0.84)Ni_(0.16) thin-film sample that exhibits a martensitic transformation with over 350\u2009K hysteresis, using an average heating rate of 85\u2009K/s and cooling rate of 275\u2009K/s. The apparatus includes an array of nanocalorimeters in an architecture designed for combinatorial studies.", "date": "2013-05-20", "date_type": "published", "publication": "Applied Physics Letters", "volume": "102", "number": "20", "publisher": "American Institute of Physics", "pagerange": "Art. No. 201902", "id_number": "CaltechAUTHORS:20130813-135504917", "issn": "0003-6951", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130813-135504917", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Harvard University", "grant_number": "DMR-0820484" }, { "agency": "Air Force Office of Scientific Research (AFOSR)", "grant_number": "FA9550-12-1-0098" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC-0004889" }, { "agency": "NIH" }, { "agency": "NSF", "grant_number": "DMR-0936384" }, { "agency": "NSF", "grant_number": "ECS-0335765" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4806972", "pmcid": "PMC3676369", "primary_object": { "basename": "ApplPhysLett_102_201902.pdf", "url": "https://authors.library.caltech.edu/records/33w9f-1sd55/files/ApplPhysLett_102_201902.pdf" }, "pub_year": "2013", "author_list": "Gregoire, John M.; Xiao, Kechao; et el." }, { "id": "https://authors.library.caltech.edu/records/18ckq-y7f69", "eprint_id": 38541, "eprint_status": "archive", "datestamp": "2023-08-19 19:33:20", "lastmod": "2023-10-23 20:33:43", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Coridan-R-H", "name": { "family": "Coridan", "given": "Robert H." }, "orcid": "0000-0003-1916-4446" }, { "id": "Shaner-M-R", "name": { "family": "Shaner", "given": "Matthew" }, "orcid": "0000-0003-4682-9757" }, { "id": "Wiggenhorn-C", "name": { "family": "Wiggenhorn", "given": "Craig" } }, { "id": "Brunschwig-B-S", "name": { "family": "Brunschwig", "given": "Bruce S." }, "orcid": "0000-0002-6135-6727" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Electrical and Photoelectrochemical Properties of WO_3/Si Tandem Photoelectrodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 American Chemical Society. \n\nReceived: December 5, 2012; Revised: February 22, 2013; Published: March 15, 2013. Published In Issue April 11, 2013. \n\nWe acknowledge the Defense Advanced Research Projects Agency (DARPA) Grant W911NF-09-2-0011 for support of R.H.C. and N.S.L. and the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award DE-SC0004993, for support of M.S., B.S.B., and N.S.L. We also acknowledge BP and the Molecular Materials Research Center of the Beckman Institute at the California Institute of Technology for support.\n\nPublished - jp311947x.pdf
Supplemental Material - jp311947x_si_001.pdf
", "abstract": "Tungsten trioxide (WO_3) has been investigated as a photoanode for water oxidation reactions in acidic aqueous conditions. Though WO_3 is not capable of performing unassisted solar-driven water splitting, WO_3 can in principle be coupled with a low band gap semiconductor, such as Si, to produce a stand-alone, tandem photocathode/photoanode p-Si/n-WO_3 system for solar fuels production. Junctions between Si and WO_3, with and without intervening ohmic contacts, were therefore prepared and investigated in detail. Thin films of n-WO_3 that were prepared directly on p-Si and n-Si substrates exhibited an onset of photocurrent at a potential consistent with expectations based on the band-edge alignment of these two materials predicted by Andersen theory. However, n-WO_3 films deposited on Si substrates exhibited much lower anodic photocurrent densities (0.02 mA cm^(\u20132) at 1.0 V vs SCE) than identically prepared n-WO_3 films that were deposited on fluorine-doped tin oxide (FTO) substrates (0.45 mA cm^(\u20132) at 1.0 V vs SCE). Deposition of n-WO_3 onto a thin layer of tin-doped indium oxide (ITO) that had been deposited on a Si substrate yielded anodic photocurrent densities that were comparable to those observed for n-WO_3 films that had been deposited onto FTO-coated glass. An increased photovoltage was observed when an n-Si/ITO Schottky junction was formed in series with the n-WO_3 film, relative to when the WO_3 was deposited directly onto the Si. Hence, inclusion of the ITO layer allowed for tandem photoelectrochemical devices to be prepared using n-WO_3 and n-Si as the light absorbers.", "date": "2013-04-11", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "117", "number": "14", "publisher": "American Chemical Society", "pagerange": "6949-6957", "id_number": "CaltechAUTHORS:20130516-133146126", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130516-133146126", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)", "grant_number": "W911NF-09-2-0011" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "BP" }, { "agency": "Caltech Beckman Institute" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp311947x", "primary_object": { "basename": "jp311947x.pdf", "url": "https://authors.library.caltech.edu/records/18ckq-y7f69/files/jp311947x.pdf" }, "related_objects": [ { "basename": "jp311947x_si_001.pdf", "url": "https://authors.library.caltech.edu/records/18ckq-y7f69/files/jp311947x_si_001.pdf" } ], "pub_year": "2013", "author_list": "Coridan, Robert H.; Shaner, Matthew; et el." }, { "id": "https://authors.library.caltech.edu/records/nyj81-9wa65", "eprint_id": 39271, "eprint_status": "archive", "datestamp": "2023-08-19 14:39:03", "lastmod": "2023-10-24 16:37:08", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Mu\u00f1oz-A-G", "name": { "family": "Mu\u00f1oz", "given": "A. G." } }, { "id": "Heine-C", "name": { "family": "Heine", "given": "C." } }, { "id": "Lublow-M", "name": { "family": "Lublow", "given": "M." } }, { "id": "Klemm-H-W", "name": { "family": "Klemm", "given": "H. W." } }, { "id": "Szab\u03cc-N", "name": { "family": "Szab\u03cc", "given": "N." } }, { "id": "Hannappel-T", "name": { "family": "Hannappel", "given": "T." }, "orcid": "0000-0002-6307-9831" }, { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H.-J." }, "orcid": "0000-0001-8433-9471" } ] }, "title": "Photoelectrochemical Conditioning of MOVPE p-InP Films for Light-Induced Hydrogen Evolution: Chemical, Electronic and Optical Properties", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 The Electrochemical Society. \n\nManuscript submitted January 3, 2013; revised manuscript received January 22, 2013. Published February 8, 2013. \n\nThe authors acknowledge the support given by the Collaborating\nResearch Group (CRG), whichmaintains the SoLiAS system at Bessy II. Financial support was given by the BMBF federal project No. 03 SF 0353A-E which is greatly acknowledged.\n\nPublished - ECS_J._Solid_State_Sci._Technol.-2013-Mu\u00f1oz-Q51-8.pdf
", "abstract": "Homoepitaxial p-InP(100) thin films prepared by MOVPE (metallorganic vapor phase epitaxy) were transformed into an InP/oxide-phosphate/Rh heterostructure by photoelectrochemical conditioning. Surface sensitive synchrotron radiation photoelectron spectroscopy indicates the formation of a mixed oxide constituted by In(PO_3)_3, InPO_4 and In_(2)O_3 as nominal components during photo-electrochemical activation. The operation of these films as hydrogen evolving photocathode proved a light-to-chemical energy conversion efficiency of 14.5%. Surface activation arises from a shift of the semiconductor electron affinity by 0.44 eV by formation of In-Cl interfacial dipoles with a density of about 10^(12) cm^(\u22122). Predominant local In2O3-like structures in the oxide introduce resonance states near the semiconductor conduction band edge imparting electron conductivity to the phosphate matrix. Surface reflectance investigations indicate an enhanced light-coupling in the layered architecture.", "date": "2013-02-08", "date_type": "published", "publication": "ECS Journal of Solid State Science and Technology", "volume": "2", "number": "4", "publisher": "Electrochemical Society", "pagerange": "Q51-Q58", "id_number": "CaltechAUTHORS:20130709-110434578", "issn": "2162-8769", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130709-110434578", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Collaborating Research Group (CRG)" }, { "agency": "Bundesministerium f\u00fcr Bildung und Forschung (BMBF)", "grant_number": "03 SF 0353A-E" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.016304jss", "primary_object": { "basename": "ECS_J._Solid_State_Sci._Technol.-2013-Mu\u00f1oz-Q51-8.pdf", "url": "https://authors.library.caltech.edu/records/nyj81-9wa65/files/ECS_J._Solid_State_Sci._Technol.-2013-Mu\u00f1oz-Q51-8.pdf" }, "pub_year": "2013", "author_list": "Mu\u00f1oz, A. G.; Heine, C.; et el." }, { "id": "https://authors.library.caltech.edu/records/8zktp-36848", "eprint_id": 38401, "eprint_status": "archive", "datestamp": "2023-08-22 08:36:30", "lastmod": "2023-10-23 20:08:09", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "John M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Liu-Xiaonao", "name": { "family": "Liu", "given": "Xiaonao" } }, { "id": "Marcin-M-R", "name": { "family": "Marcin", "given": "Martin" } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "Jian" } } ] }, "title": "Scanning droplet cell for high throughput electrochemical and photoelectrochemical measurements", "ispublished": "pub", "full_text_status": "public", "keywords": "catalysts; chemical variables measurement; drops; electrochemical electrodes", "note": "\u00a9 2013 American Institute of Physics. \n\nReceived 15 October 2012; accepted 22 January 2013; published online 12 February 2013. \n\nThis material is based upon work performed by the Joint\nCenter for Artificial Photosynthesis, a DOE Energy Innovation\nHub, supported through the Office of Science of the U.S.\nDepartment of Energy (Award No. DE-SC0004993). The authors\nthank Mr. Lung-Sheng Lin for assistance in fabrication\nof the cell and Mr. William Fisher of Lawrence Berkeley National\nLaboratory for assistance in fabrication of the capillary\nfor the reference electrode. The authors also thank Dr.\nEric McFarland, Dr. Nathan Lewis, Dr. Carl Koval, and Dr.\nJoachim Lewerenz for helpful discussions.\n\nPublished - RevSciInstrum_84_024102.pdf
", "abstract": "High throughput electrochemical techniques are widely applied in material discovery and optimization. For many applications, the most desirable electrochemical characterization requires a three-electrode cell under potentiostat control. In high throughput screening, a material library is explored by either employing an array of such cells, or rastering a single cell over the library. To attain this latter capability with unprecedented throughput, we have developed a highly integrated, compact scanning droplet cell that is optimized for rapid electrochemical and photoeletrochemical measurements. Using this cell, we screened a quaternary oxide library as (photo)electrocatalysts for the oxygen evolution (water splitting) reaction. High quality electrochemical measurements were carried out and key electrocatalytic properties were identified for each of 5456 samples with a throughput of 4 s per sample.", "date": "2013-02", "date_type": "published", "publication": "Review of Scientific Instruments", "volume": "84", "number": "2", "publisher": "American Institute of Physics", "pagerange": "Art. No. 024102", "id_number": "CaltechAUTHORS:20130509-154116203", "issn": "0034-6748", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130509-154116203", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1063/1.4790419", "primary_object": { "basename": "RevSciInstrum_84_024102.pdf", "url": "https://authors.library.caltech.edu/records/8zktp-36848/files/RevSciInstrum_84_024102.pdf" }, "pub_year": "2013", "author_list": "Gregoire, John M.; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/mpw4y-4v451", "eprint_id": 37896, "eprint_status": "archive", "datestamp": "2023-08-22 08:35:56", "lastmod": "2023-10-23 19:06:21", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Baricuatro-J-H", "name": { "family": "Baricuatro", "given": "Jack H." } }, { "id": "Soto-J-C", "name": { "family": "Soto", "given": "Jos\u00e9 C." } }, { "id": "Cummins-K-D", "name": { "family": "Cummins", "given": "Kyle D." } }, { "id": "Soriaga-M-P", "name": { "family": "Soriaga", "given": "Manuel P." }, "orcid": "0000-0002-0077-6226" } ] }, "title": "High-resolution electron energy loss spectroscopy of anions chemisorbed on electrode surfaces: The effect of counter cations", "ispublished": "pub", "full_text_status": "restricted", "keywords": "AES and HREELS of chemisorbed anions; Cation-exchange at anionic adlayers; UHV-EC of Pd(111) electrodes; Benzoquinone sulfonate chemisorbed on Pd(111); High-resolution electron energy loss spectroscopy", "note": "\u00a9 2012 Elsevier B.V. \n\nReceived 23 October 2012. Received in revised form 5 November 2012. Accepted 6 November 2012. Available online 15 November 2012. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The surface spectral analysis was supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the adlayer preparation and characterization were supported by The Welch Foundation (A-1064). JES would like to acknowledge a graduate fellowship provided by the National Institute of General Medical Sciences and the National Institutes of Health.", "abstract": "In the course of experiments that included Auger electron spectroscopy (AES) and high-resolution electron energy loss spectroscopy (HREELS) on cation exchange at benzoquinone sulfonate chemisorbed on a Pd(111) electrode, it was found that, whereas the AES spectra remained invariant as the counter cation was varied from H^+ to K^+ to Cs^+, profound changes occurred in the HREELS spectra. Specifically, the intensity of the spectral features decreased noticeably when H^+ was replaced with K^+. And, when the K^+ ions were exchanged with Cs^+, nothing but a flat-line (dead) spectrum was observed; even the elastic peak was completely attenuated. When the Cs^+ ions were displaced by protons, the initial undiminished spectrum was fully restored. This outcome, while unrelated to cation-exchange selectivity, is of exceptional significance in surface electron spectroscopy. It appears that the positive ions on the surface attracted the low-energy incident electrons such that backscattering towards the energy analyzer was hindered; partially by K^+ but totally by the larger Cs^+ ion. The use of HREELS to examine the molecular integrity of chemisorbed anionic species must thus take cognizance of the possibility that the counter cation chosen to preserve interfacial-layer electroneutrality can have a profound effect. To circumvent such complication, low-valent and small-radii cations will have to be employed. In addition, although subject to instrument limitations, higher incident-electron energies could be adopted. AES, with incident-electron energies in the kV range, is impervious to the presence of counter cations.", "date": "2013-02", "date_type": "published", "publication": "Electrochemistry Communications", "volume": "27", "publisher": "Elsevier", "pagerange": "176-179", "id_number": "CaltechAUTHORS:20130412-084406072", "issn": "1388-2481", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130412-084406072", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Robert A. Welch Foundation", "grant_number": "A-1064" }, { "agency": "National Institute of General Medical Sciences" }, { "agency": "NIH Graduate Fellowship" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1016/j.elecom.2012.11.005", "pub_year": "2013", "author_list": "Baricuatro, Jack H.; Soto, Jos\u00e9 C.; et el." }, { "id": "https://authors.library.caltech.edu/records/7efrp-r4852", "eprint_id": 38658, "eprint_status": "archive", "datestamp": "2023-08-19 14:28:56", "lastmod": "2023-10-23 22:39:20", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Gregoire-J-M", "name": { "family": "Gregoire", "given": "J. M." }, "orcid": "0000-0002-2863-5265" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "C." }, "orcid": "0000-0002-1698-6754" }, { "id": "Mitrovic-S", "name": { "family": "Mitrovic", "given": "S." }, "orcid": "0000-0001-8913-8505" }, { "id": "Liu-Xiaonao", "name": { "family": "Liu", "given": "X." } }, { "id": "Marcin-M-R", "name": { "family": "Marcin", "given": "M." } }, { "id": "Cornell-E-W", "name": { "family": "Cornell", "given": "E. W." } }, { "id": "Fan-J", "name": { "family": "Fan", "given": "J." } }, { "id": "Jin-Jian", "name": { "family": "Jin", "given": "J." } } ] }, "title": "Combined Catalysis and Optical Screening for High Throughput Discovery of Solar Fuels Catalysts", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2013 The Electrochemical Society. \n\nManuscript submitted December 10, 2012; revised manuscript received January 21, 2013. Published January 30, 2013. This was Paper 1716 presented at the Honolulu, Hawaii, Meeting of the Society, October 7\u201312, 2012. \n\nThis material is based upon work performed by the Joint Center\nfor Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: The experiments and data interpretation were supported through the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; J.F. acknowledges financial support from the National Science Foundation of China (21003106 and 20873122). The authors thank Lung-Sheng Lin for assistance in fabrication of the cell and William Fisher of Lawrence Berkeley National Laboratory for assistance in fabrication of the capillary for the reference electrode. The authors also thank Dr. Joel Haber, Eric McFarland, Nathan Lewis, Carl Koval and Joachim Lewerenz for helpful discussions.\n\nPublished - J._Electrochem._Soc.-2013-Gregoire-F337-42.pdf
", "abstract": "Considerable research and development efforts are being devoted to the efficient generation of solar fuels. A solar fuels device\ncouples a solar photoabsorber with catalysts to convert solar energy to chemical energy via reactions such as oxygen evolution\n(water splitting). Widespread deployment of this technology hinges upon discovery of new materials through efforts such as the high\nthroughput screening of oxygen evolution catalysts, as discussed in this manuscript. We derive an expression for the efficiency of\nthe oxygen evolution catalyst that combines catalytic and optical properties. Using this hybrid efficiency, we screen 5456 samples in\na (Fe-Co-Ni-Ti)O_x pseudo-quaternary catalyst library using automated, high throughput electrochemical and optical experiments.\nThe observed compositional trends in this catalyst efficiency lead to the discovery of a new high performance composition region.", "date": "2013-01-30", "date_type": "published", "publication": "Journal of the Electrochemical Society", "volume": "160", "number": "4", "publisher": "Electrochemical Society", "pagerange": "F337-F342", "id_number": "CaltechAUTHORS:20130523-112147351", "issn": "0013-4651", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130523-112147351", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "National Science Foundation of China", "grant_number": "21003106" }, { "agency": "National Science Foundation of China", "grant_number": "20873122" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/2.035304jes", "primary_object": { "basename": "J._Electrochem._Soc.-2013-Gregoire-F337-42.pdf", "url": "https://authors.library.caltech.edu/records/7efrp-r4852/files/J._Electrochem._Soc.-2013-Gregoire-F337-42.pdf" }, "pub_year": "2013", "author_list": "Gregoire, J. M.; Xiang, C.; et el." }, { "id": "https://authors.library.caltech.edu/records/eg4r2-9gw60", "eprint_id": 36773, "eprint_status": "archive", "datestamp": "2023-08-19 14:20:11", "lastmod": "2023-10-23 15:45:54", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "McKone-J-R", "name": { "family": "McKone", "given": "James R." }, "orcid": "0000-0001-6445-7884" }, { "id": "Peiterick-A-P", "name": { "family": "Peiterick", "given": "Adam P." } }, { "id": "Gray-H-B", "name": { "family": "Gray", "given": "Harry B." }, "orcid": "0000-0002-7937-7876" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Hydrogen Evolution from Pt/Ru-Coated p-Type WSe_2 Photocathodes", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society. \n\nReceived: August 29, 2012; published: November 30, 2012. \n\nThis material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under Award Number DE-SC0004993. The contributions from JRM and HBG were supported by CCSER (the Gordon and Betty Moore Foundation). JRM is supported by a graduate research fellowship from the Office of Science of the U.S. Department of Energy.\n\nPublished - ja308581g.pdf
Supplemental Material - ja308581g_si_001.pdf
", "abstract": "Crystalline p-type WSe_2 has been grown by a chemical vapor transport method. After deposition of noble metal catalysts, p-WSe_2 photocathodes exhibited thermodynamically based photoelectrode energy-conversion efficiencies of >7% for the hydrogen evolution reaction under mildly acidic conditions, and were stable under cathodic conditions for at least 2 h in acidic as well as in alkaline electrolytes. The open circuit potentials of the photoelectrodes in contact with the H^(+)/H_2 redox couple were very close to the bulk recombination/diffusion limit predicted from the Shockley diode equation. Only crystals with a prevalence of surface step edges exhibited a shift in flat-band potential as the pH was varied. Spectral response data indicated effective minority-carrier diffusion lengths of ~1 \u03bcm, which limited the attainable photocurrent densities in the samples to ~15 mA cm^(\u20132) under 100 mW cm^(\u20132) of Air Mass 1.5G illumination.", "date": "2013-01-09", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "135", "number": "1", "publisher": "American Chemical Society", "pagerange": "223-231", "id_number": "CaltechAUTHORS:20130205-103231488", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130205-103231488", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" }, { "agency": "Gordon and Betty Moore Foundation" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ja308581g", "primary_object": { "basename": "ja308581g.pdf", "url": "https://authors.library.caltech.edu/records/eg4r2-9gw60/files/ja308581g.pdf" }, "related_objects": [ { "basename": "ja308581g_si_001.pdf", "url": "https://authors.library.caltech.edu/records/eg4r2-9gw60/files/ja308581g_si_001.pdf" } ], "pub_year": "2013", "author_list": "McKone, James R.; Peiterick, Adam P.; et el." }, { "id": "https://authors.library.caltech.edu/records/3nasw-59k31", "eprint_id": 44273, "eprint_status": "archive", "datestamp": "2023-08-19 14:02:11", "lastmod": "2023-10-26 00:21:07", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Lewerenz-H-J", "name": { "family": "Lewerenz", "given": "H. J." }, "orcid": "0000-0001-8433-9471" } ] }, "title": "On the Structure of the Helmholtz Layer and its Implications on Electrode Kinetics", "ispublished": "pub", "full_text_status": "public", "keywords": "Helmholtz layer structure, electrochemical kinetics,\nelectroreflectance, distance tunneling spectroscopy, electron injection,\ntransition state concept", "note": "\u00a9 2013 Electrochemical Society. Support by the DFG, project LE 1192-4 and by the Joint Center for Artificial\nPhotosynthesis is gratefully acknowledged. Dedicated to the memory of Dieter M. Kolb.\n\nPublished - ECS_Trans.-2013-Lewerenz-3-20.pdf
", "abstract": "Concepts and selected experiments on the structure of the Helmholtz double layer at the metal- and semiconductor - electrolyte phase boundary are reviewed. The widely used microcapacitor approach of the double layer and its limitations are assessed. Observations on the influence of the electrode potential on the energetic position of surface states at the Ag-electrolyte contact are compared to the predictions of classical charge transfer models that are based on transition state theory where adiabatic tunneling is assumed. Distance tunneling spectroscopy on Au(111) surfaces shows pronounced variations in tunneling barrier heights that are connected to the inner structure of the Helmholtz layer and implications on electrode kinetics are presented. At the semiconductor-electrolyte contact, the influence of the electrode potential on a charge injecting species that results in photocurrent doubling is reviewed for low- and higher doped Si(111) electrodes, showing that the complex that injects electrons into the conduction band is located outside the semiconductor surface. The observations are correlated with the search for low overpotential earth abundant electrocatalysts for solar fuel generation of solar fuels.", "date": "2013", "date_type": "published", "publication": "ECS Transactions", "volume": "50", "number": "52", "publisher": "Electrochemical Society", "pagerange": "3-20", "id_number": "CaltechAUTHORS:20140312-093801401", "issn": "1938-5862", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20140312-093801401", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Deutsche Forschungsgemeinschaft (DFG)", "grant_number": "LE 1192-4" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1149/05052.0003ecst", "primary_object": { "basename": "ECS_Trans.-2013-Lewerenz-3-20.pdf", "url": "https://authors.library.caltech.edu/records/3nasw-59k31/files/ECS_Trans.-2013-Lewerenz-3-20.pdf" }, "pub_year": "2013", "author_list": "Lewerenz, H. J." }, { "id": "https://authors.library.caltech.edu/records/q367t-vbq61", "eprint_id": 36203, "eprint_status": "archive", "datestamp": "2023-08-19 13:37:33", "lastmod": "2023-10-20 22:22:17", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Haussener-S", "name": { "family": "Haussener", "given": "Sophia" }, "orcid": "0000-0002-3044-1662" }, { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Spurgeon-J-M", "name": { "family": "Spurgeon", "given": "Joshua M." }, "orcid": "0000-0002-2987-0865" }, { "id": "Ardo-S", "name": { "family": "Ardo", "given": "Shane" }, "orcid": "0000-0001-7162-6826" }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" }, { "id": "Weber-A-Z", "name": { "family": "Weber", "given": "Adam Z." }, "orcid": "0000-0002-7749-1624" } ] }, "title": "Modeling, simulation, and design criteria for photoelectrochemical water-splitting systems", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 Royal Society of Chemistry.\n\nReceived 15th August 2012, Accepted 28th September 2012.\nFirst published on the web 01 Oct 2012. \n\nWe acknowledge the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the U.S. Department of Energy under award number DE-SC0004993. S.A. acknowledges support from a U.S. Department of Energy, Office of Energy Efficiency and Renewable Energy (EERE) Postdoctoral Research Award under the EERE Fuel Cell Technologies Program. We thank Sivagaminathan Balasubramanian for fruitful discussions.\n\nSupplemental Material - c2ee23187e.pdf
", "abstract": "A validated multi-physics numerical model that accounts for charge and species conservation, fluid flow, and electrochemical processes has been used to analyze the performance of solar-driven photoelectrochemical water-splitting systems. The modeling has provided an in-depth analysis of conceptual designs, proof-of-concepts, feasibility investigations, and quantification of performance. The modeling has led to the formulation of design guidelines at the system and component levels, and has identified quantifiable gaps that warrant further research effort at the component level. The two characteristic generic types of photoelectrochemical systems that were analyzed utilized: (i) side-by-side photoelectrodes and (ii) back-to-back photoelectrodes. In these designs, small electrode dimensions (mm to cm range) and large electrolyte heights were required to produce small overall resistive losses in the system. Additionally, thick, non-permeable separators were required to achieve acceptably low rates of product crossover.", "date": "2012-12", "date_type": "published", "publication": "Energy and Environmental Science", "volume": "5", "number": "12", "publisher": "Royal Society of Chemistry", "pagerange": "9922-9935", "id_number": "CaltechAUTHORS:20130107-104614254", "issn": "1754-5692", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130107-104614254", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-SC0004993" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1039/c2ee23187e", "primary_object": { "basename": "c2ee23187e.pdf", "url": "https://authors.library.caltech.edu/records/q367t-vbq61/files/c2ee23187e.pdf" }, "pub_year": "2012", "author_list": "Haussener, Sophia; Xiang, Chengxiang; et el." }, { "id": "https://authors.library.caltech.edu/records/zvrkb-fkj65", "eprint_id": 35250, "eprint_status": "archive", "datestamp": "2023-08-22 06:57:36", "lastmod": "2023-10-20 15:54:06", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Xiang-Chengxiang", "name": { "family": "Xiang", "given": "Chengxiang" }, "orcid": "0000-0002-1698-6754" }, { "id": "Meng-A-C", "name": { "family": "Meng", "given": "Andrew C." } }, { "id": "Lewis-N-S", "name": { "family": "Lewis", "given": "Nathan S." }, "orcid": "0000-0001-5245-0538" } ] }, "title": "Evaluation and optimization of mass transport of redox species in silicon microwire-array photoelectrodes", "ispublished": "pub", "full_text_status": "public", "keywords": "semiconductor/liquid junctions; Si microwire arrays; COMSOL Multiphysics", "note": "\u00a9 2012 National Academy of Sciences. \n\nEdited by Thomas J. Meyer, University of North Carolina at Chapel Hill, Chapel Hill, NC, and approved July 23, 2012 (received for review December 14, 2011). Published online before print August 16, 2012. \n\nThis work was supported by the U.S. Department of Energy, Grant DE-FG0203ER15483 and by the Caltech Center for Sustainable Energy Research (CCSER). One of us (A.C.M.) acknowledges support from Caltech's Summer Undergraduate Research Fellowship program. \n\nAuthor contributions: C.X., A.C.M., and N.S.L. designed research; C.X. and A.C.M. performed research; C.X. and A.C.M. analyzed data; and C.X., A.C.M., and N.S.L. wrote the paper.\n\nPublished - PNAS-2012-Xiang-15622-7.pdf
Supplemental Material - pnas.1118338109_SI.pdf
", "abstract": "Physical integration of a Ag electrical contact internally into a metal/substrate/microstructured Si wire array/oxide/Ag/electrolyte photoelectrochemical solar cell has produced structures that display relatively low ohmic resistance losses, as well as highly efficient mass transport of redox species in the absence of forced convection. Even with front-side illumination, such wire-array based photoelectrochemical solar cells do not require a transparent conducting oxide top contact. In contact with a test electrolyte that contained 50 mM/5.0 mM of the cobaltocenium^(+/0) redox species in CH_3CN\u20131.0 M LiClO_4, when the counterelectrode was placed in the solution and separated from the photoelectrode, mass transport restrictions of redox species in the internal volume of the Si wire array photoelectrode produced low fill factors and limited the obtainable current densities to 17.6 mA cm^(-2) even under high illumination. In contrast, when the physically integrated internal Ag film served as the counter electrode, the redox couple species were regenerated inside the internal volume of the photoelectrode, especially in regions where depletion of the redox species due to mass transport limitations would have otherwise occurred. This behavior allowed the integrated assembly to operate as a two-terminal, stand-alone, photoelectrochemical solar cell. The current density vs. voltage behavior of the integrated photoelectrochemical solar cell produced short-circuit current densities in excess of 80 mA cm^(-2) at high light intensities, and resulted in relatively low losses due to concentration overpotentials at 1 Sun illumination. The integrated wire array-based device architecture also provides design guidance for tandem photoelectrochemical cells for solar-driven water splitting.", "date": "2012-09-25", "date_type": "published", "publication": "Proceedings of the National Academy of Sciences of the United States of America", "volume": "109", "number": "39", "publisher": "National Academy of Sciences", "pagerange": "15622-15627", "id_number": "CaltechAUTHORS:20121101-150325621", "issn": "0027-8424", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20121101-150325621", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-FG02-03ER15483" }, { "agency": "Caltech Center for Sustainable Energy Research" }, { "agency": "Caltech Summer Undergraduate Research Fellowship (SURF)" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1073/pnas.1118338109", "pmcid": "PMC3465373", "primary_object": { "basename": "PNAS-2012-Xiang-15622-7.pdf", "url": "https://authors.library.caltech.edu/records/zvrkb-fkj65/files/PNAS-2012-Xiang-15622-7.pdf" }, "related_objects": [ { "basename": "pnas.1118338109_SI.pdf", "url": "https://authors.library.caltech.edu/records/zvrkb-fkj65/files/pnas.1118338109_SI.pdf" } ], "pub_year": "2012", "author_list": "Xiang, Chengxiang; Meng, Andrew C.; et el." }, { "id": "https://authors.library.caltech.edu/records/3f1mf-5kb90", "eprint_id": 36478, "eprint_status": "archive", "datestamp": "2023-08-19 12:22:49", "lastmod": "2023-10-20 23:12:10", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Jeon-Seokmin", "name": { "family": "Jeon", "given": "Seokmin" }, "orcid": "0000-0002-1230-906X" }, { "id": "Kim-Hyungjun", "name": { "family": "Kim", "given": "Hyungjun" }, "orcid": "0000-0001-8261-9381" }, { "id": "Goddard-W-A-III", "name": { "family": "Goddard", "given": "William A., III" }, "orcid": "0000-0003-0097-5716" }, { "id": "Atwater-H-A", "name": { "family": "Atwater", "given": "Harry A." }, "orcid": "0000-0001-9435-0201" } ] }, "title": "DFT Study of Water Adsorption and Decomposition on a Ga-Rich\n GaP(001)(2\u00d74) Surface", "ispublished": "pub", "full_text_status": "public", "note": "\u00a9 2012 American Chemical Society. Received: April 30, 2012.\nRevised: July 3, 2012. Published: July 9, 2012. This work was supported by DARPA and the Joint Center for Artificial Photosynthesis (JCAP), a project of the Office of Basic Energy Sciences, US Department of Energy. S. Jeon thanks the Kwanjeong Educational Foundation for support. H. Kim and W. A. Goddard acknowledge support from the WCU (World Class University) program through the National Research Foundation of Korea funded by the Ministry of Education, Science and Technology (R31-2008-000-10055-0).\n\nPublished - jp3041555.pdf
Supplemental Material - jp3041555_si_001.pdf
", "abstract": "We investigate the adsorption and decomposition states of a water molecule on a Ga-rich GaP(001)(2\u00d74) surface using the PBE flavor of density functional theory (DFT). We selected the GaP(001)(2\u00d74) mixed dimer surface reconstruction model to represent the Ga-rich GaP(001)(2\u00d74) surface. Because our focus is on reactions between a single water molecule and the surface, the surface water coverage is kept at 0.125 ML, which corresponds to one water molecule in the (2\u00d74) unit cell. We report here the geometries and energies for an exhaustive set of adsorption and decomposition states induced by a water molecule on the (2\u00d74) unit cell. Our results support a mechanism in which (1) the first step is the molecular adsorption, with the water molecule forming a Lewis acid\u2013Lewis base bond to the sp^2 Ga atom of either the first-layer Ga\u2013P mixed dimer or the second layer Ga\u2013Ga dimers using an addition reaction, (2) which is followed by dissociation of the adsorbed H_2O to form the HO/H decomposition state in which the hydroxyl moiety bonds with surface sp^2 Ga atoms, while the hydrogen moiety binds with the first-layer P atom, (3) which is followed by the O/2H decomposition state, in which the oxygen moiety forms bridged Ga\u2013O\u2013Ga structures with surface Ga dimers while one H bonds with the first-layer P atom and the other to surface sp^2 Ga atoms. (4) We find that driving off the hydrogen as H_2 leads to the surface oxide state, bridged Ga\u2013O\u2013Ga structures. This surface oxide formation reaction is exothermic relative to the energy of H_2O plus the reconstructed surface. These results provide guidelines for experiments and theory to validate the key steps and to obtain kinetics data for modeling the growth processes.", "date": "2012-08-23", "date_type": "published", "publication": "Journal of Physical Chemistry C", "volume": "116", "number": "33", "publisher": "American Chemical Society", "pagerange": "17604-17612", "id_number": "CaltechAUTHORS:20130118-105914846", "issn": "1932-7447", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20130118-105914846", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Defense Advanced Research Projects Agency (DARPA)" }, { "agency": "Joint Center for Artificial Photosynthesis (JCAP)" }, { "agency": "Department of Energy (DOE)" }, { "agency": "Kwanjeong Educational Foundation" }, { "agency": "Ministry of Education, Science and Technology (Korea)", "grant_number": "R31-2008-000-10055-0" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/jp3041555", "primary_object": { "basename": "jp3041555.pdf", "url": "https://authors.library.caltech.edu/records/3f1mf-5kb90/files/jp3041555.pdf" }, "related_objects": [ { "basename": "jp3041555_si_001.pdf", "url": "https://authors.library.caltech.edu/records/3f1mf-5kb90/files/jp3041555_si_001.pdf" } ], "pub_year": "2012", "author_list": "Jeon, Seokmin; Kim, Hyungjun; et el." }, { "id": "https://authors.library.caltech.edu/records/zezqj-xw950", "eprint_id": 114637, "eprint_status": "archive", "datestamp": "2023-08-22 05:10:16", "lastmod": "2023-10-24 15:05:32", "type": "article", "metadata_visibility": "show", "creators": { "items": [ { "id": "Manthiram-Karthish", "name": { "family": "Manthiram", "given": "Karthish" }, "orcid": "0000-0001-9260-3391" }, { "id": "Alivisatos-A-Paul", "name": { "family": "Alivisatos", "given": "A. Paul" }, "orcid": "0000-0001-6895-9048" } ] }, "title": "Tunable Localized Surface Plasmon Resonances in Tungsten Oxide Nanocrystals", "ispublished": "pub", "full_text_status": "public", "keywords": "Plasmonic nanoparticles ,Nanoparticles, Electrical conductivity, Surface plasmon resonance, Nanorods; Colloid and Surface Chemistry; Biochemistry; General Chemistry; Catalysis", "note": "\u00a9 2012 American Chemical Society. \n\nReceived 5 December 2011. Published online 23 February 2012. Published in issue 7 March 2012. \n\nWe thank B. Beberwyck, D. Britt, C. Choi, D. Grauer, P. K. Jain, M. Lucas, Y. Surendranath, and J. Wang for useful discussions and advice. This work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub funded by the Office of Science of the U.S. Department of Energy under Award DE-AC02-05CH11231. K.M. gratefully acknowledges the support of the Department of Energy Office of Science Graduate Fellowship Program (DOE SCGF), made possible in part by the American Recovery and Reinvestment Act of 2009 and administered by ORISE\u2013ORAU under Contract DE-AC05-06OR23100. \n\nThe authors declare no competing financial interest.\n\nSupplemental Material - ja211363w_si_001.pdf
", "abstract": "Transition-metal oxide nanocrystals are interesting candidates for localized surface plasmon resonance hosts because they exhibit fascinating properties arising from the unique character of their outer-d valence electrons. WO_(3\u2212\u03b4) nanoparticles are known to have intense visible and near-IR absorption, but the origin of the optical absorption has remained unclear. Here we demonstrate that metallic phases of WO_(3\u2212\u03b4) nanoparticles exhibit a strong and tunable localized surface plasmon resonance, which opens up the possibility of rationally designing plasmonic tungsten oxide nanoparticles for light harvesting, bioimaging, and sensing.", "date": "2012-03-07", "date_type": "published", "publication": "Journal of the American Chemical Society", "volume": "134", "number": "9", "publisher": "American Chemical Society", "pagerange": "3995-3998", "id_number": "CaltechAUTHORS:20220505-565529000", "issn": "0002-7863", "official_url": "https://resolver.caltech.edu/CaltechAUTHORS:20220505-565529000", "rights": "No commercial reproduction, distribution, display or performance rights in this work are provided.", "funders": { "items": [ { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC02-05CH11231" }, { "agency": "American Recovery and Reinvestment Act of 2009" }, { "agency": "Department of Energy (DOE)", "grant_number": "DE-AC05-06OR23100" } ] }, "local_group": { "items": [ { "id": "JCAP" } ] }, "doi": "10.1021/ja211363w", "primary_object": { "basename": "ja211363w_si_001.pdf", "url": "https://authors.library.caltech.edu/records/zezqj-xw950/files/ja211363w_si_001.pdf" }, "pub_year": "2012", "author_list": "Manthiram, Karthish and Alivisatos, A. Paul" } ]