@article{5cf429fba61142309271bcdefa7572e7,
title = "Theory-driven design of high-valence metal sites for water oxidation confirmed using in situ soft X-ray absorption",
abstract = "The efficiency with which renewable fuels and feedstocks are synthesized from electrical sources is limited at present by the sluggish oxygen evolution reaction (OER) in pH-neutral media. We took the view that generating transition-metal sites with high valence at low applied bias should improve the activity of neutral OER catalysts. Here, using density functional theory, we find that the formation energy of desired Ni 4+ sites is systematically modulated by incorporating judicious combinations of Co, Fe and non-metal P. We therefore synthesized NiCoFeP oxyhydroxides and probed their oxidation kinetics with in situ soft X-ray absorption spectroscopy (sXAS). In situ sXAS studies of neutral-pH OER catalysts indicate ready promotion of Ni 4+ under low overpotential conditions. The NiCoFeP catalyst outperforms IrO 2 and retains its performance following 100 h of operation. We showcase NiCoFeP in a membrane-free CO 2 electroreduction system that achieves a 1.99 V cell voltage at 10 mA cm -2, reducing CO 2 into CO and oxidizing H 2 O to O 2 with a 64% electricity-to-chemical-fuel efficiency.",
author = "Xueli Zheng and Bo Zhang and {De Luna}, Phil and Yufeng Liang and Riccardo Comin and Oleksandr Voznyy and Lili Han and {Garc{\'i}a De Arquer}, {F. Pelayo} and Min Liu and Dinh, {Cao Thang} and Tom Regier and Dynes, {James J.} and Sisi He and Xin, {Huolin L.} and Huisheng Peng and David Prendergast and Xiwen Du and Sargent, {Edward H.}",
note = "Funding Information: 149 154 10.1038/nchem.2886 EN Xueli Zheng Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada Institute of New-Energy Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China http://orcid.org/0000-0002-6800-2649 Bo Zhang Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China http://orcid.org/0000-0003-3875-1259 Phil De Luna Department of Materials Science and Engineering, University of Toronto, 184 College Street, Toronto, Ontario M5S 3E4, Canada http://orcid.org/0000-0002-7729-8816 Yufeng Liang The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Riccardo Comin Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada Oleksandr Voznyy Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada http://orcid.org/0000-0002-8656-5074 Lili Han Institute of New-Energy Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA Center for Electron Microscopy, TUT-FEI Joint Laboratory, Institute for New Energy Materials & Low-Carbon Technologies, School of Materials Science and Engineering, Tianjin University of Technology, Tianjin, 300384, China F. Pelayo Garc{\'i}a de Arquer Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada Min Liu Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada Cao Thang Dinh Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada Tom Regier Canadian Light Source, Inc. (CLSI), 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada James J. Dynes Canadian Light Source, Inc. (CLSI), 44 Innovation Boulevard, Saskatoon, Saskatchewan S7N 2V3, Canada Sisi He State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China Huolin L. Xin Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973, USA http://orcid.org/0000-0002-6521-868X Huisheng Peng State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China David Prendergast The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA Xiwen Du Institute of New-Energy Materials, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China Edward H. Sargent Department of Electrical and Computer Engineering, University of Toronto, 35 St George Street, Toronto, Ontario M5S 1A4, Canada http://orcid.org/0000-0001-8057-9558 nchem.2886 10.1038/nchem.2886 2016 08 29 2017 09 29 2017 November 20 The efficiency with which renewable fuels and feedstocks are synthesized from electrical sources is limited at present by the sluggish oxygen evolution reaction (OER) in pH-neutral media. We took the view that generating transition-metal sites with high valence at low applied bias should improve the activity of neutral OER catalysts. Here, using density functional theory, we find that the formation energy of desired Ni 4+ sites is systematically modulated by incorporating judicious combinations of Co, Fe and non-metal P. We therefore synthesized NiCoFeP oxyhydroxides and probed their oxidation kinetics with in situ soft X-ray absorption spectroscopy (sXAS). In situ sXAS studies of neutral-pH OER catalysts indicate ready promotion of Ni 4+ under low overpotential conditions. The NiCoFeP catalyst outperforms IrO 2 and retains its performance following 100 h of operation. We showcase NiCoFeP in a membrane-free CO 2 electroreduction system that achieves a 1.99 V cell voltage at 10 mA cm –2 , reducing CO 2 into CO and oxidizing H 2 O to O 2 with a 64% electricity-to-chemical-fuel efficiency. Publisher Copyright: {\textcopyright} 2018 Macmillan Publishers Limited, part of Springer Nature. All rights reserved.",
year = "2018",
month = feb,
day = "1",
doi = "10.1038/nchem.2886",
language = "English (US)",
volume = "10",
pages = "149--154",
journal = "Nature Chemistry",
issn = "1755-4330",
publisher = "Nature Publishing Group",
number = "2",
}
