Decoupling the catalytic and degradation mechanisms of cobalt active sites during acidic water oxidation
Abstract Advancement of iridium-free catalysts for the low-pH oxygen evolution reaction (OER) is required to enable multi-gigawatt-scale proton-exchange water electrolysis. Cobalt-based materials might address this requirement, but little is known about the mechanism of operation of these OER catalysts at low pH. Here we investigate the nature and evolution of the active cobalt sites along with charge- and mass-transfer processes that support their catalytic function within a cobalt–iron–lead oxide material using in situ spectroscopic, gravimetric and electrochemical techniques. We demonstrate that corrosion of the cobalt sites and their reformation through electrooxidation of dissolved Co 2+ do not affect the catalytic mechanism and are decoupled from the OER. The OER-coupled charge transfer is supported by Co (3+δ)+ -oxo-species, which are structurally different from those reported for alkaline/near-neutral conditions and are formed on a relatively slow timescale of minutes. These mechanistic insights might assist in developing genuinely practical catalysts for this vital technology.
Authors
- Rosalie K. Hocking (ORCID: https://orcid.org/0000-0002-2213-8786)
- Jie Xiao (ORCID: https://orcid.org/0000-0002-2320-6111)
- Darcy Simondson (ORCID: https://orcid.org/0000-0002-8370-5027)
- Douglas R. MacFarlane (ORCID: https://orcid.org/0000-0001-5963-9659)
- Ronny Golnak (ORCID: https://orcid.org/0000-0002-5461-5284)
- Manjunath Chatti (ORCID: https://orcid.org/0000-0001-5046-2316)
- Ioannis Spanos (ORCID: https://orcid.org/0000-0001-5737-4992)
- Bernt Johannessen (ORCID: https://orcid.org/0000-0002-3027-0816)
- Travis E. Jones (ORCID: https://orcid.org/0000-0001-8921-7641)
- Marc F. Tesch (ORCID: https://orcid.org/0000-0001-7480-7200)
- Alexandr N. Simonov (ORCID: https://orcid.org/0000-0003-3063-6539)
- Brittany V. Kerr
- Shannon A. Bonke (ORCID: https://orcid.org/0000-0002-3285-4356)
- Jining Guo (ORCID: https://orcid.org/0009-0002-1775-6974)
Institutions
- Australian Nuclear Science and Technology Organisation (AU)
- Los Alamos National Laboratory (US)
- University of Wollongong (AU)
- University of Cambridge (GB)
- Helmholtz-Zentrum Berlin für Materialien und Energie (DE)
- Australian Synchrotron (AU)
- Max Planck Institute for Chemical Energy Conversion (DE)
- Monash University (AU)
- Swinburne University of Technology (AU)
Publication Details
- Journal
- Nature Energy
- Published
- 2025-07-16
- DOI
- https://doi.org/10.1038/s41560-025-01812-x
- Citations
- 21
- Primary Topic
- Electrocatalysts for Energy Conversion
- Type
- article
- Field-Weighted Citation Impact
- 7.63
Funders
- Australian Nuclear Science and Technology Organisation
- Australian Synchrotron
- Deutscher Akademischer Austauschdienst
- University of Wollongong
- Monash University
- Bundesministerium für Bildung und Forschung
- Australian Renewable Energy Agency
- Helmholtz-Zentrum Berlin für Materialien und Energie
- Australian Research Council
- Office of Naval Research
- Office of Naval Research Global
- Los Alamos National Laboratory