Binder‐Free Fe III Cu I Mo IV Electrocatalysts for Durable Water Splitting at Industrial Current Density

The development of highly active and durable electrocatalysts based on earth‐abundant Fe, Cu, and Mo via an energy‐efficient one‐pot synthesis marks a decisive advancement in alkaline water electrolysis. Herein, we report a ligand (isothiocyanate)‐assisted, coordination‐guided one‐pot strategy for the synthesis of an Fe III Cu I Mo IV electrocatalyst. Compositional tuning between Cu‐rich and Mo‐rich variants induces pronounced morphological evolution, including cubic and spherical structures. Among them, Fe 3 CuMo 11 , with an average particle size of 28 ± 6 nm, exhibits exceptional bifunctional activity in 1 m KOH, evidenced by overpotentials of only 85 mV for hydrogen evolution reaction (HER) at 10 mA cm −2 and 90 mV for the oxygen evolution reaction (OER) at 10 mA cm −2 along with a low Tafel slope of 70.2 mV dec − 1 . Remarkably, a two‐electrode electrolyzer assembled using Fe 3 CuMo 11 /NF as both the anode and cathode achieves a cell voltage of merely 2.082 V at 200 mA cm −2 , maintaining exceptional operational stability for over 500 h under alkaline water electrolysis. The superior catalytic performance is attributed to synergistic coupling among FeOOH, Cu 2 S, and MoS 2 phases, which offer optimal adsorption energetics and accelerates charge‐transfer kinetics. Our study offers a robust platform for industrially relevant alkaline water electrolysis.