Synergistic Regulation of Bimetallic Electronic Structure and Electrochemical Activation‐Driven Surface Reconstruction for Fabricating High‐Performance NiFe‐Based Alloy/Oxyhydroxide Electrocatalysts Toward Efficient Oxygen Evolution

Aiming at the core mechanism whereby the activity of electrocatalytic OER strongly relies on surface active sites, this study presents an efficient catalyst design strategy integrating bimetallic electronic structure tuning with electrochemical activation‐induced surface reconstruction.Ni–Fe alloy catalysts with varying atomic ratios were fabricated on 316 stainless steel substrates via electrodeposition. Systematic investigations reveal that Ni–Fe alloys exhibit remarkably superior OER performance compared to monometallic Ni/Fe catalysts, with the NiFe alloy at an 8:2 molar ratio demonstrating the optimal intrinsic activity. Cyclic voltammetry activation further induces in situ formation of a Ni–Fe alloy/oxyhydroxide composite phase on the alloy surface. High‐valent Ni/Fe species enhance MO bond covalency, optimizing reaction intermediate adsorption and lowering the OER energy barrier. Electrochemical measurements show that the composite phase maintains stable operation for over 70 h at a current density of 10 mA cm −2 . By elucidating the evolution mechanism of alloy precursors into high‐activity composite phases via surface reconstruction, this study provides a theoretical foundation and technical pathway for the in situ interface design and structural optimization of efficient OER catalysts by revealing the evolution mechanism of alloy precursors into high‐activity composite phases through surface reconstruction.