Self‐Reconstruction of Dual‐Morphology Copper‐Iron Selenides for Cost‐Effective Oxygen Evolution Toward Industrial Alkaline Water Splitting

Abstract Nickel and cobalt dominate as electrocatalysts for the oxygen evolution reaction (OER). Despite the advantages of iron in terms of abundance and cost, the insufficient catalytic activity of iron‐rich catalysts is limited by the inherent poor electrical conductivity. Herein, a dual‐morphology CuFe‐Se/CFF catalyst through a one‐step hydrothermal method, integrating the high conductivity of copper selenides with Cu‐Fe electronic interaction, is designed. The unique nanoblock‐nanorod architecture imparts simultaneous superhydrophilicity and superaerophobicity, enabling a low overpotential of 330 mV at industrial‐grade 1000 mA cm −2 with 620 h durability in alkaline media, and a cell voltage of 1.99 V at 1000 mA cm −2 for 259 h in anion exchange membrane water electrolyzers (AEMWE) devices—outperforming most reported Ni/Co‐based catalysts and commercial RuO 2 . The experimental and characterization results reveal that the Cu‐Fe electronegativity difference drives charge redistribution, promoting self‐reconstruction into active FeOOH with residual SeO x . Density functional theory (DFT) calculations demonstrate that SeO x ‐modulated FeOOH optimizes the d ‐band center, tuning the adsorption/desorption of OER intermediates at Fe active sites and thereby lowering the overpotential. This work establishes a durable, Ni/Co‐free OER catalyst paradigm, offering design insights for efficient industrial water splitting.