Isotope-dependent Tafel analysis probes proton transfer kinetics during electrocatalytic water splitting
Proton transfer plays an important role in both hydrogen and oxygen evolution reactions during electrocatalytic water splitting to produce green hydrogen. However, directly adapting the conventional proton/deuterium kinetic isotope effect to study proton transfer in heterogeneous electrocatalytic processes is challenging. Here we propose using the shift in the Tafel slope between protic and deuteric electrolytes, or the Tafel slope isotope effect, as an effective probe of proton transfer characteristics. Comparison of the Tafel slope isotope effect for diverse hydrogen and oxygen evolution reaction electrocatalysts in different pH environments reveals that proton transfer is both pH and structure dependent. Using ruthenium oxide as an example, we show that local structure modification can change the rate-determining step from an electrochemical, concerted proton-electron transfer step to a chemical step and improve the oxygen evolution activity in acid. The isotope-dependent Tafel analysis will facilitate a better understanding of the proton transfer behaviours during electrocatalytic processes and provide guidance for designing efficient electrocatalysts.
Authors
- Bo Song (ORCID: https://orcid.org/0000-0003-2000-5071)
- Lin Gu (ORCID: https://orcid.org/0000-0002-7504-031X)
- Jinzhen Huang (ORCID: https://orcid.org/0000-0002-0274-0454)
- Xiaorong Zhu (ORCID: https://orcid.org/0000-0001-8007-3047)
- Hongyuan Sheng (ORCID: https://orcid.org/0000-0002-0494-4418)
- Daxing Hua
- Song Jin (ORCID: https://orcid.org/0000-0001-8693-7010)
- Sida Jiang (ORCID: https://orcid.org/0000-0002-6647-1222)
- Jiecai Han (ORCID: https://orcid.org/0000-0002-5892-7787)
- R. Dominic Ross (ORCID: https://orcid.org/0000-0002-4192-8230)
- Qinghua Zhang (ORCID: https://orcid.org/0000-0001-9086-7000)
- Ping Xu (ORCID: https://orcid.org/0000-0002-1516-4986)
- Yafei Li (ORCID: https://orcid.org/0000-0002-6136-863X)
- Ran Wang (ORCID: https://orcid.org/0000-0002-2034-7189)
- Jun Biao Lu (ORCID: https://orcid.org/0000-0003-0858-8577)
- Lin Lei (ORCID: https://orcid.org/0009-0000-9786-9658)
- Xianjie Wang (ORCID: https://orcid.org/0000-0003-1688-2768)
Institutions
- University of Wisconsin System (US)
- University of Wisconsin–Madison (US)
- Nanjing Normal University (CN)
- Nantong University (CN)
- Harbin Institute of Technology (CN)
- Fudan University (CN)
- Paul Scherrer Institute (CH)
- Institute of Physics (CN)
- Zhejiang University (CN)
Publication Details
- Journal
- Nature Chemistry
- Published
- 2025-09-09
- DOI
- https://doi.org/10.1038/s41557-025-01934-5
- Citations
- 11
- Primary Topic
- Electrocatalysts for Energy Conversion
- Type
- article
- Field-Weighted Citation Impact
- 4.00
Funders
- National Science Foundation
- U.S. Department of Energy
- Natural Science Foundation of Shanghai
- National Natural Science Foundation of China
- China Scholarship Council
- Office of Science
- National Science Fund for Distinguished Young Scholars
- Division of Materials Research
- Division of Chemistry
- Argonne National Laboratory