Microwave-assisted synthesis of multimetal oxygen-evolving catalysts

•Mo-doped FeNi3 nanoparticles are synthesized by a facile microwave synthesis process.•The doped Mo lowers the FeNi3 particle size, and increases the catalytic activity/durability.•An excellent OER overpotential of 280 mV is achieved at 10 mA cm− 2.

Oxygen evolution reaction (OER) plays a pivotal role in water-splitting. Here, we report a facile method to synthesize multimetal supported on commercial carbon black via a time-saving microwave process. Crystalline FeNi3 nanoparticles homogeneously doped with Mo are formed via a microwave treatment and activated to metal oxyhydroxide in-situ during cyclic voltammetry test with overpotential of only 280 mV at 10 mA cm− 2 for OER in alkaline electrolyte, outperforming RuO2. Our synthesis methodology is a promising alternative for large-scale production, delivering a valuable contribution to catalyst preparation and electrocatalytic water oxidation research.