Surface Reconstruction‐Free Stability Achieving Highly Anticorrosive Seawater Splitting

Surface reconstruction, although often associated with enhanced activity through the lattice oxygen mechanism (LOM), can expose vulnerable sites that accelerate chloride-induced corrosion. It is demonstrated that a silver and cerium co-doped iron manganese oxide catalyst achieves high oxygen evolution reaction (OER) activity while maintaining a stable, reconstruction-free surface under alkaline seawater conditions. Operando X-ray absorption spectroscopy (XAS), complemented by the previous operando Raman analysis, reveals no detectable rearrangement of chemical environment or electronic structures across the OER-relevant potential window. The catalyst achieves a low overpotential of 210 mV to reach 10 mA cm^-2 in alkaline seawater, while maintaining 99.5% faradaic efficiency for oxygen evolution. By adopting the electrocatalyst into an anion exchange membrane (AEM) electrolyzer (5×5 cm² of active area) for direct seawater electrolysis, the durability tests show a stable electrolysis current of 5000 mA for at least 250 h, while the blank electrolyzer fails in 1 h with significant corrosion. These findings strongly support the hypothesis that inhibiting surface reconstruction can effectively enhance seawater corrosion resistance without sacrificing catalytic performance.