Engineering Electronic Structures of Ni‐Based Heterostructures for Accelerated Reconstruction Toward Efficient Alkaline Seawater Oxidation

ABSTRACT Developing efficient and stable anodes for seawater electrolysis is critical for sustainable hydrogen production but remains challenging due to competing chloride reactions and corrosion. Herein, we report a hierarchical heterostructure comprising NiFe layered double hydroxide (LDH) nanosheets grown on P‐doped NiMoO4 nanorods (P‐NiMoO4/NiFe LDH) as a high‐performance anode for alkaline seawater oxidation. The heterostructure leverages synergistic interfacial interactions to enhance oxygen evolution reaction (OER) activity and selectivity. The interfacial Ni─O─Fe bridges facilitate electron transfer, generating high‐valence Ni species that optimize intermediate adsorption and reaction kinetics. This catalyst delivers exceptional performance in alkaline seawater, requiring only 284, 348, and 462 mV overpotentials to achieve 0.5, 1.0, and 2.0 A·cm −2 , respectively, alongside remarkable stability and OER selectivity in alkaline seawater. Experimental analyses reveal that the P‐doped NiMoO 4 substrate not only promotes in situ reconstruction into active oxyhydroxides but also electrostatically repels chloride ions, thereby suppressing corrosion. This work highlights heterojunction engineering as a promising strategy to develop durable, high‐efficiency electrocatalysts for industrial‐scale seawater splitting.