Breaking the Alkaline HOR Barrier: Process‐Engineered Strategies for Breaking the Kinetic Bottleneck of Alkaline Hydrogen Oxidation Reaction

ABSTRACT The hydrogen oxidation reaction (HOR) is a key process for efficient energy conversion in alkaline anion exchange membrane fuel cells (AEMFCs). In this review, recent progress in HOR electrocatalysts is systematically summarized, and the underlying mechanisms, including hydrogen binding energy (HBE) theory, bifunctional theory, and other related models, are discussed in detail. Particular emphasis is placed on process‐engineered strategies for HOR enhancement, among which hydrogen spillover is highlighted as a mechanistic extension of the bifunctional theory that enables spatial decoupling of hydrogen activation and hydroxide‐assisted charge transfer. In addition, regulation of interfacial water structure, optimization of cation effects, and exploitation of the dynamic evolution of electrocatalysts are discussed as complementary approaches to improving HOR performance. Finally, future research directions are outlined, including the development of advanced in situ/operando characterization techniques and machine‐learning‐assisted catalyst design, aiming to provide theoretical guidance and technical references for the rational development of highly efficient HOR electrocatalysts.