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Title: Towards identifying the active sites on RuO 2 (110) in catalyzing oxygen evolution

Abstract

While the surface atomic structure of RuO 2 has been well studied in ultra high vacuum, much less is known about the interaction between water and RuO 2 in aqueous solution. In this work, in situ surface X-ray scattering measurements combined with density functional theory (DFT) were used to determine the surface structural changes on single-crystal RuO2(110) as a function of potential in acidic electrolyte. The redox peaks at 0.7, 1.1 and 1.4 V vs. reversible hydrogen electrode (RHE) could be attributed to surface transitions associated with the successive deprotonation of –H 2O on the coordinatively unsaturated Ru sites (CUS) and hydrogen adsorbed to the bridging oxygen sites. At potentials relevant to the oxygen evolution reaction (OER), an –OO species on the Ru CUS sites was detected, which was stabilized by a neighboring –OH group on the Ru CUS or bridge site. Combining potential-dependent surface structures with their energetics from DFT led to a new OER pathway, where the deprotonation of the –OH group used to stabilize –OO was found to be rate-limiting.

Authors:
ORCiD logo [1]; ORCiD logo [2];  [3]; ORCiD logo [4];  [5];  [6];  [7]; ORCiD logo [8];  [3];  [9];  [10];  [11]; ORCiD logo [3]; ORCiD logo [4];  [4]; ORCiD logo [12]
  1. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Mechanical Engineering
  2. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Research Lab. of Electronics
  3. Technical Univ. of Denmark, Lyngby (Denmark). Dept. of Energy Conversion and Storage
  4. Technical Univ. of Denmark, Lyngby (Denmark). Section for Surface Physics and Catalysis, Dept. of Physics
  5. SLAC National Accelerator Lab., Menlo Park, CA (United States)
  6. Argonne National Lab. (ANL), Argonne, IL (United States)
  7. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Materials Science and Engineering
  8. Oregon State Univ., Corvallis, OR (United States). School of Chemical, Biological, and Environmental Engineering
  9. Argonne National Lab. (ANL), Argonne, IL (United States). X-ray Science Division
  10. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Mechanical Engineering; Univ. di Milano-Bicocca (Italy). Dipartimento di Scienza dei Materiali
  11. Univ. of Copenhagen (Denmark). Dept. of Chemistry
  12. Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Mechanical Engineering; Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Research Lab. of Electronics; Massachusetts Inst. of Technology (MIT), Cambridge, MA (United States). Dept. of Materials Science and Engineering
Publication Date:
Research Org.:
SLAC National Accelerator Lab., Menlo Park, CA (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1419931
Grant/Contract Number:
9455; AC02-06CH11357; AC02-76SF00515; ACI-1548562
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Energy & Environmental Science
Additional Journal Information:
Journal Volume: 10; Journal Issue: 12; Journal ID: ISSN 1754-5692
Publisher:
Royal Society of Chemistry
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE

Citation Formats

Rao, Reshma R., Kolb, Manuel J., Halck, Niels Bendtsen, Pedersen, Anders Filsoe, Mehta, Apurva, You, Hoydoo, Stoerzinger, Kelsey A., Feng, Zhenxing, Hansen, Heine A., Zhou, Hua, Giordano, Livia, Rossmeisl, Jan, Vegge, Tejs, Chorkendorff, Ib, Stephens, Ifan E. L., and Shao-Horn, Yang. Towards identifying the active sites on RuO 2 (110) in catalyzing oxygen evolution. United States: N. p., 2017. Web. doi:10.1039/c7ee02307c.
Rao, Reshma R., Kolb, Manuel J., Halck, Niels Bendtsen, Pedersen, Anders Filsoe, Mehta, Apurva, You, Hoydoo, Stoerzinger, Kelsey A., Feng, Zhenxing, Hansen, Heine A., Zhou, Hua, Giordano, Livia, Rossmeisl, Jan, Vegge, Tejs, Chorkendorff, Ib, Stephens, Ifan E. L., & Shao-Horn, Yang. Towards identifying the active sites on RuO 2 (110) in catalyzing oxygen evolution. United States. doi:10.1039/c7ee02307c.
Rao, Reshma R., Kolb, Manuel J., Halck, Niels Bendtsen, Pedersen, Anders Filsoe, Mehta, Apurva, You, Hoydoo, Stoerzinger, Kelsey A., Feng, Zhenxing, Hansen, Heine A., Zhou, Hua, Giordano, Livia, Rossmeisl, Jan, Vegge, Tejs, Chorkendorff, Ib, Stephens, Ifan E. L., and Shao-Horn, Yang. 2017. "Towards identifying the active sites on RuO 2 (110) in catalyzing oxygen evolution". United States. doi:10.1039/c7ee02307c.
@article{osti_1419931,
title = {Towards identifying the active sites on RuO 2 (110) in catalyzing oxygen evolution},
author = {Rao, Reshma R. and Kolb, Manuel J. and Halck, Niels Bendtsen and Pedersen, Anders Filsoe and Mehta, Apurva and You, Hoydoo and Stoerzinger, Kelsey A. and Feng, Zhenxing and Hansen, Heine A. and Zhou, Hua and Giordano, Livia and Rossmeisl, Jan and Vegge, Tejs and Chorkendorff, Ib and Stephens, Ifan E. L. and Shao-Horn, Yang},
abstractNote = {While the surface atomic structure of RuO2 has been well studied in ultra high vacuum, much less is known about the interaction between water and RuO2 in aqueous solution. In this work, in situ surface X-ray scattering measurements combined with density functional theory (DFT) were used to determine the surface structural changes on single-crystal RuO2(110) as a function of potential in acidic electrolyte. The redox peaks at 0.7, 1.1 and 1.4 V vs. reversible hydrogen electrode (RHE) could be attributed to surface transitions associated with the successive deprotonation of –H2O on the coordinatively unsaturated Ru sites (CUS) and hydrogen adsorbed to the bridging oxygen sites. At potentials relevant to the oxygen evolution reaction (OER), an –OO species on the Ru CUS sites was detected, which was stabilized by a neighboring –OH group on the Ru CUS or bridge site. Combining potential-dependent surface structures with their energetics from DFT led to a new OER pathway, where the deprotonation of the –OH group used to stabilize –OO was found to be rate-limiting.},
doi = {10.1039/c7ee02307c},
journal = {Energy & Environmental Science},
number = 12,
volume = 10,
place = {United States},
year = 2017,
month =
}

Journal Article:
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