Facile synthesis of bimetallic Ni–Fe phosphide as robust electrocatalyst for oxygen evolution reaction in alkaline media

Bimetallic Ni–Fe phosphide electrocatalysts were in-situ synthesized through direct phosphorization of metal salts on carbon cloth (CC). The Fe dopant remarkably enhances the OER performance of Ni 2 P in alkaline medium through the electronic structure modulation of Ni. The (Fe 0.5 Ni 0.5 ) 2 P/CC electrode, composed of uniform films coated on carbon fibers, delivers a low overpotential of 260 mV with a small Tafel slope of 45 mV·dec −1 at the current density of 100 mA cm −2 , outperforming most reported non-noble electrocatalysts and commercial RuO 2 electrocatalyst. The (Fe 0.5 Ni 0.5 ) 2 P/CC also displays superior electrochemical stability at high current density . An appropriate Fe dopant level facilitates the in-situ transformation of Ni–Fe phosphides into active NiFeOOH during alkaline OER. This work simplifies the synthesis procedure of metal phosphides.