Dynamic Stability of OER Electrocatalysts in Water Electrolyzers: Multiscale Deactivation Mechanisms and Regulation Strategies

Abstract

Water electrolysis is widely acknowledged as a vital pathway for achieving deep decarbonization and facilitating large-scale integration of renewable energy sources. Nonetheless, the anodic oxygen evolution reaction (OER) presents a significant efficiency bottleneck due to its inherently sluggish kinetics associated with multi-electron and proton transfer. In addition to the necessity for high catalytic activity, the long-term stability of OER electrocatalysis has garnered increasing attention. This review focuses on stability under realistic conditions and on understanding and elucidating OER deactivation mechanisms at the microscopic, mesoscopic, and macroscopic levels. At the micro level, the analysis delves into the disruption of dynamic phase equilibrium, stoichiometric deviations caused by selective dissolution, and deactivation resulting from the lattice oxygen mechanism. On the meso scale, it examines the extent of surface reconstruction, the inadequacy of nanomechanical robustness, and catalyst-layer delamination prompted by ripening and agglomeration.At the macro level, it considers corrosion resulting from start-stop cycling, component degradation, and the effects of harsh operational environments. Furthermore, the review summarizes current strategies aimed at enhancing stability, emphasizing intrinsic stability design as a foundational element, supplemented by dynamic stability regulation and optimization of operational conditions. Collectively, these approaches facilitate sustained catalytic performance under high potentials and extended operational periods, paving the way for durable electrocatalytic systems. Lastly, future research should prioritize the stabilization of OER electrocatalysis and its scalable application in industrial water electrolysis.