Ag2S-Engineered Heterojunction Enhances Overall Water Splitting Efficiency of NiSx Catalysts

Abstract

Ag2S/NiSx heterostructures are designed as efficient electrocatalysts for overall water splitting. Ag 2 S modifies the electronic structure and induces a large number of active sites. Strong interactions between the interfaces of the heterostructure lead to lower charge transfer resistance and enhance the intrinsic activity of active sites. As expected, Ag 2 S/NiS x demonstrated excellent OER catalytic performance in alkaline environments, with an OER current density of 10, 50, 100 mA cm -2 obtained at 1 M KOH at an overpotential of only 42, 137, 180 mV. When used in a two-electrode electrolyzer, Ag 2 S/NiS x can achieve 100 mA cm -2 at a low voltage of 1.81 V. This work provides an efficient way to enhance the overall catalytic performance of non-precious metal electrocatalysts.