Preparation of highly active MoNi4 alloys in 3D porous nanostructures and their application as bifunctional electrocatalysts for overall water splitting

The major challenges of replacing noble-metal electrocatalysts for hydrogen evolution reaction and oxygen evolution reaction in alkaline electrolytes are stability- and kinetics-related. Here we report the synthesis of MoNi 4 electrocatalysts covered by MoO 2 nanosheets on carbon cloth. Originating from the high intrinsic catalytic activity of MoNi 4 nanoalloy, the 3D porous structure provides many exposed active sites and high conductivity. The sample exhibited high activity with an overpotential of 23 mV and 253 mV, a low Tafel slope of 47 mV dec −1 and 136 mV dec −1 at a current density of 10 mA cm −2 for HER and OER, respectively.