Hexavalent Ru Catalyst with Both Lattice Oxygen and Metal Ion Mechanisms Coactive for Water Oxidation
Green hydrogen from water requires the development of efficient and low-cost catalysts for anodic oxygen evolution reaction (OER), which is the main obstacle for electrochemical water splitting. Herein, we focus on an OER catalyst (Pb<sub>2</sub>CoRuO<sub>7</sub>) featuring Ru<sup>6+</sup>, which exhibits an ultralow overpotential of 176 mV at 10 mA cm<sup>-2</sup> and a Tafel slope of 30.52 mV dec<sup>-1</sup> vs 340 mV at 10 mA cm<sup>-2</sup> and a Tafel slope of 111.54 mV dec<sup>-1</sup> for RuO<sub>2</sub> in 1.0 M KOH solution. In situ X-ray absorption experiments demonstrated the gradual conversion of Ru<sup>5+</sup> ions into high-valence Ru<sup>6+</sup>, while a portion of Co<sup>3+</sup> ions transformed into Co<sup>4+</sup> during the OER process. Density functional theory calculations revealed that the ultrahigh OER activity of Pb<sub>2</sub>CoRuO<sub>7</sub> was contributed by both metal-site adsorbate evolution (MAE) at the Co site and the lattice-oxygen-vacancy-site (LOV) mechanism involving lattice oxygen located between Ru<sup>6+</sup> and Co. Our work presents a new and unusual OER catalyst where both the MAE and LOV mechanisms cooperatively facilitate catalytic activity.
Authors
- Zhiwei Hu (ORCID: https://orcid.org/0000-0003-0324-2227)
- Chang‐Yang Kuo (ORCID: https://orcid.org/0000-0003-1968-8020)
- Shu‐Chih Haw (ORCID: https://orcid.org/0009-0008-9529-8204)
- Yalei Fan (ORCID: https://orcid.org/0000-0003-2605-0383)
- Changqing Jin (ORCID: https://orcid.org/0000-0001-6578-0149)
- Daixin Ye (ORCID: https://orcid.org/0000-0001-6020-429X)
- Jianfa Zhao (ORCID: https://orcid.org/0000-0002-7507-9441)
- Cheng‐Wei Kao (ORCID: https://orcid.org/0000-0003-3434-3258)
- Linjuan Zhang (ORCID: https://orcid.org/0000-0003-4704-5807)
- Ting‐Shan Chan (ORCID: https://orcid.org/0000-0001-5220-1611)
- Yucheng Huang (ORCID: https://orcid.org/0000-0002-7818-8811)
- Chao Jing (ORCID: https://orcid.org/0000-0003-0339-9742)
- Hongbin Zhao (ORCID: https://orcid.org/0000-0002-5712-2493)
- Shengjie Zhang
- Chien‐Te Chen
- Yu‐Chieh Ku
- Yanzhuo Li
Institutions
- Shanghai University (CN)
- National Yang Ming Chiao Tung University (TW)
- Chinese Academy of Sciences (CN)
- National Synchrotron Radiation Research Center (TW)
- Max Planck Institute for Chemical Physics of Solids (DE)
- Centre for Sustainable Energy (GB)
- FZU ‒ Institute of Physics of the Academy of Sciences of the Czech Republic (CZ)
- Shanghai Institute of Applied Physics (CN)
- Institute of Physics (CN)
- University of Chinese Academy of Sciences (CN)
Publication Details
- Journal
- Journal of the American Chemical Society
- Published
- 2025-07-16
- DOI
- https://doi.org/10.1021/jacs.5c08425
- Citations
- 11
- Primary Topic
- Electrocatalysts for Energy Conversion
- Type
- article
- Field-Weighted Citation Impact
- 4.00
Funders
- National Natural Science Foundation of China
- Shanghai City Youth Science and Technology Star Project
- National Key Research and Development Program of China