ABSTRACT Achieving ampere‐level current densities in anion‐exchange membrane (AEM) water electrolyzers is severely hindered by the sluggish kinetics and rapid degradation of non‐noble‐metal oxygen evolution reaction (OER) electrocatalysts. Herein, we introduce a targeted electrochemical corrosion‐cation exchange (EC‐CE) coupling strategy to engineer a robust Ni(OH) 2 @Co 3 Fe 7 hybrid electrocatalyst. This architecture is specifically designed to bypass conventional linear scaling relations by triggering the highly efficient oxide pathway mechanism (OPM) at heteronuclear dual sites. Extended x‐ray absorption fine structure (EXAFS) reveals that the EC‐CE process forms an asymmetric Ni─O─Co motif, while in situ Raman and theoretical calculations suggest that this motif can survive during the OER process. Crucially, this motif lowers metal‐oxygen covalency and weakens d–p–d hybridization, suppressing metal‐site over‐oxidation and dissolution to achieve long‐term stability. Furthermore, in situ spectroscopy, isotope labeling, and theoretical calculations demonstrate that the alkaline OER process is dominated by the OPM pathway on heteronuclear Ni─Co dual sites, exhibiting significantly higher coupling efficiency than that on homonuclear Co─Co dual sites. By leveraging ultrafast kinetics and structural resilience, the Ni(OH) 2 @Co 3 Fe 7 achieves over 1000 h of durability for both OER and AEMWE at ampere‐level current densities (≥1.0 A cm −2 ), outperforming many state‐of‐the‐art transition metal‐based materials.
Huang et al. (Fri,) studied this question.