Oxyanion-Triggered Discrepant Oxide Pathways Via Tailoring Reconstruction of Non-Noble Catalysts for Water Oxidation

Constructing heterogeneous dual-site catalysts is anticipated for oxygen evolution reaction (OER). However, compared to the adsorbate evolution mechanism (AEM), the triggering oxide pathway mechanism (OPM) for catalysts poses challenges due to elusive structural evolution and low intrinsic activity. Herein, considering the distinct adsorption propensity of heterogeneous Ni-Fe sites toward differential intermediates (OH-O), the PO₄^3--induced deep reconstruction triggers a dual-site Ni-Fe discrepant oxide pathway mechanism (DOPM) for R-PO₄-NiCoFeOOH. Highly oxidized Ni/Fe actives exhibit moderate intermediate *OH/*O adsorption energies and form adjacent sites with modulated spatial configuration, stimulating localized discrepant radical coupling (Ni-*OH-O*-Fe) around leachable PO_x sites, expediting OER kinetics. Thus, R-PO₄-NiCoFeOOH demonstrates ultralow overpotentials of 230/258 mV at 100 mA cm^-2 and robust 1500-h durability in alkaline/seawater. Additionally, the anion exchange membrane water electrolyzer merely requires a cell voltage of 1.81 V to deliver 1.0 A cm^-2 and maintains 300-h stable operation. This work provides a methodology for triggering the DOPM of catalysts.