Degradation mechanisms and rational design ofdur-able oxygen evolution electrocatalysts under acidicconditions

Proton exchange membrane water electrolysis (PEMWE) stands as a pivotal technology for scalable green hydrogenpro-duction, yet its efficiency is hindered by the instability of oxygen evolution reaction (OER) catalysts under acidic andox-idative conditions. This review article systematically examines the degradation mechanisms of OER electrocatalysts inPEMWE, categorizing them into intrinsic and extrinsic factors. Intrinsic degradation arises from active metal dissolution(e.g., Ru/Ir oxidative leaching), dynamic surface reconstruction, and structural collapse induced by lattice oxygenparti-cipation via the lattice oxygen oxidation mechanism (LOM). Extrinsic instability stems from corrosion-prone supports(e.g., carbon-based materials or oxidized Ti substrates) and weakened catalyst-support interactions due to binderde-gradation or bubble-induced detachment. To address these challenges, advanced strategies are discussed, includingelectronic modulation of active sites (e.g., alloying, doping), rational utilization of surface reconstruction, suppression ofLOM pathways, and the integration of corrosion-resistant supports with optimized metal-support interactions.Further-more, self-supported catalysts and superaerophobic electrode designs are highlighted to mitigate delamination.Fi-nally, critical research gaps are identified, emphasizing the need for standardized stability evaluation protocols, in-situ/operando characterization techniques, and holistic integration of catalyst design with PEMWE system components(e.g., membranes, flow fields) to bridge laboratory advancements with industrial-scale applications.