Advances in Ru-based acidic OER electrocatalysts: Addressing the activity-stability trade-off

Ruthenium (Ru)-based materials have garnered considerable attention as highly commercial potential anode electrocatalysts for proton exchange membrane water electrolyzer (PEMWE). However, its active sites are susceptible to over-oxidation under strongly acidic and high-potential conditions, which not only severely compromises the long-term stability of PEMWE, but also poses a challenge for large-scale commercialization. Currently, recent advancements in Ru-based catalysts have focused on achieving a balance between activity and stability to meet the stringent requirements of PEMWE for efficient, stable, and cost-effective acid-stable anode. Our review summarizes the recent progress in Ru-based acidic OER electrocatalysts. A comprehensive understanding of design principles for Ru-based catalysts is first present, including the optimization of reaction and degradation mechanisms, as well as strategies to overcome the activity-stability trade-off. Then, we systematically elaborate upon four main modification strategies for Ru-based catalysts, representative examples in practical PEMWE are also provided. Finally, we advocate the future research directions on these materials, as well as the potential prospects and challenges associated with commercialization. Convinced that this review will not only enhances the fundamental understanding of Ru-based catalysts but also provides valuable insights for the development of the next generation of economic anode catalysts for PEMWE. • The importance of researching efficient and stable Ru-based OER electrocatalysts in the context of green H 2 production technology is emphasized. • The mechanisms of reaction and destabilization mechanisms of Ru-based catalysts are discussed. • Feasible strategies for addressing the activity-stability trade-off of Ru-based catalysts based on the latest research findings are generalized. • An outlook for the development of efficient and stable Ru-based anode in PEMWE is provided.