Series Reports from Professor Wei’s Group of Chongqing University: Advancements in Electrochemical Energy Conversions (2/4): Report 2: High-Performance Water Splitting Electrocatalysts

Abstract

The unavailability of high-performance and cost-effective electrocatalysts has impeded the large-scale deployment of alkaline water electrolyzers. Professor Zidong Wei's group has focused on resolving critical challenges in industrial alkaline electrolysis, particularly elucidating hydrogen and oxygen evolution reaction (HER/OER) mechanisms while addressing the persistent activity-stability trade-off. This review summarizes their decade-long progress in developing advanced electrodes, analyzing the origins of sluggish alkaline HER kinetics and OER stability limitations. Professor Wei proposes a unifying “12345 Principle” as an optimization framework. For HER electrocatalysts, they have identified that metal/metal oxide interfaces create synergistic “chimney effect” and “local electric field enhancement effect”, enhancing selective intermediate adsorption, interfacial water enrichment/reorientation, and mass transport under industrial high-polarization conditions. Regarding OER, innovative strategies, including dual-ligand synergistic modulation, lattice oxygen suppression, and self-repairing surface construction, are demonstrated to balance oxygen species adsorption, optimize spin states, and dynamically reinforce metal-oxygen bonds for concurrent activity-stability enhancement. The review concludes by addressing remaining challenges in long-term industrial durability and suggesting future research priorities.

Keywords

Alkaline water splitting / Hydron evolution reaction / Oxygen evolution reaction / Intrinsic activity / Stability

Conflicts of Interest

The authors declare that they have no conflict of interest.

Acknowledgements

Authors acknowledge the financial supports from the National Key R&D Program of China (2021YFB4000300) and National Science Foundation for Young Scientists of China (Grant No. 22408030).

Author Contributions

Doctor Ling Zhang and Professor Li Li collaborated on this review. Wang-Yang Wu, Qiu-Yue Hu, and Shi-Dan Yang assisted in gathering and curating the literature. Professor Rui-Jin Liao offered crucial policy guidance for this review. As the Principal Investigator responsible for funding, Professor Zi-Dong Wei was instrumental in this project by proposing the review's core conceptual framework, overseeing the research design, and providing strategic policy support throughout the process.

Data Availability

This study did not generate any new datasets. All data analyzed are from publicly available sources, as cited in the manuscript.

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