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Title: Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands

Abstract

Here, transition metal oxides show great promise as Earth-abundant catalysts for the oxygen evolution reaction in electrochemical water splitting. However, progress in the development of highly active oxide nanostructures is hampered by a lack of knowledge of the location and nature of the active sites. Here we show, through atom-resolved scanning tunnelling microscopy, X-ray spectroscopy and computational modelling, how hydroxyls form from water dissociation at under coordinated cobalt edge sites of cobalt oxide nanoislands. Surprisingly, we find that an additional water molecule acts to promote all the elementary steps of the dissociation process and subsequent hydrogen migration, revealing the important assisting role of a water molecule in its own dissociation process on a metal oxide. Inspired by the experimental findings, we theoretically model the oxygen evolution reaction activity of cobalt oxide nanoislands and show that the nanoparticle metal edges also display favourable adsorption energetics for water oxidation under electrochemical conditions.

Authors:
 [1];  [2];  [3]; ORCiD logo [4];  [5]; ORCiD logo [1];  [6];  [1]
  1. Aarhus Univ., Aarhus (Denmark)
  2. SLAC National Accelerator Lab., Menlo Park, CA (United States); Trinity College Dublin, Dublin (Ireland)
  3. Univ. of Manchester, Manchester (United Kingdom)
  4. Stanford Univ., Stanford, CA (United States)
  5. Institute for Storage Ring Facilities, Aarhus (Denmark)
  6. Univ. of Pennsylvania, Philadelphia, PA (United States)
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:
1349283
Grant/Contract Number:
AC02-76SF00515
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 8; Journal Issue: 1; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE; electrocatalysis; scanning probe microscopy; surfaces, interfaces and thin films

Citation Formats

Fester, J., García-Melchor, M., Walton, A. S., Bajdich, M., Li, Z., Lammich, L., Vojvodic, A., and Lauritsen, J. V.. Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands. United States: N. p., 2017. Web. doi:10.1038/ncomms14169.
Fester, J., García-Melchor, M., Walton, A. S., Bajdich, M., Li, Z., Lammich, L., Vojvodic, A., & Lauritsen, J. V.. Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands. United States. doi:10.1038/ncomms14169.
Fester, J., García-Melchor, M., Walton, A. S., Bajdich, M., Li, Z., Lammich, L., Vojvodic, A., and Lauritsen, J. V.. Mon . "Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands". United States. doi:10.1038/ncomms14169. https://www.osti.gov/servlets/purl/1349283.
@article{osti_1349283,
title = {Edge reactivity and water-assisted dissociation on cobalt oxide nanoislands},
author = {Fester, J. and García-Melchor, M. and Walton, A. S. and Bajdich, M. and Li, Z. and Lammich, L. and Vojvodic, A. and Lauritsen, J. V.},
abstractNote = {Here, transition metal oxides show great promise as Earth-abundant catalysts for the oxygen evolution reaction in electrochemical water splitting. However, progress in the development of highly active oxide nanostructures is hampered by a lack of knowledge of the location and nature of the active sites. Here we show, through atom-resolved scanning tunnelling microscopy, X-ray spectroscopy and computational modelling, how hydroxyls form from water dissociation at under coordinated cobalt edge sites of cobalt oxide nanoislands. Surprisingly, we find that an additional water molecule acts to promote all the elementary steps of the dissociation process and subsequent hydrogen migration, revealing the important assisting role of a water molecule in its own dissociation process on a metal oxide. Inspired by the experimental findings, we theoretically model the oxygen evolution reaction activity of cobalt oxide nanoislands and show that the nanoparticle metal edges also display favourable adsorption energetics for water oxidation under electrochemical conditions.},
doi = {10.1038/ncomms14169},
journal = {Nature Communications},
number = 1,
volume = 8,
place = {United States},
year = {Mon Jan 30 00:00:00 EST 2017},
month = {Mon Jan 30 00:00:00 EST 2017}
}

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Free Publicly Available Full Text
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Cited by: 9works
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