Ni₂P(O)/Fe₂P(O) Interface Can Boost Oxygen Evolution Electrocatalysis

Abstract

Oxygen evolution reaction (OER) plays a paramount role in renewable energy technologies. However, the slow kinetics of OER seriously limits the overall performance and commercialization. Here, we rationally design a metallic Ni2P/Fe2P interface, which can be in situ oxidized to a Ni2P(O)/Fe2P(O) interface to enhance OER efficiency, with active doped oxyhydroxides and phosphates on the surface and conductive phosphide in the bulk. The resulting catalysts require a low overpotential of 179 mV to achieve a current density of 10 mA/cm2 (without iR compensation) and can continuously drive OER for 120 h without any obvious degradation, which rivals most reported OER catalysts. These results suggest that we are able to design multicomponent metallic precatalysts to construct most active surface layers and conductive bulks, further boosting OER performance for real-world electrolysis utilization.