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

Abstract

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 MoNi4 electrocatalysts covered by MoO2 nanosheets on carbon cloth. Originating from the high intrinsic catalytic activity of MoNi4 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.