Coupling interface structure in NixS/Cu5FeS4 hybrid with enhanced electrocatalytic activity for alkaline hydrogen evolution reaction

Bornite (Cu5FeS4) exhibits great potential for the alkaline hydrogen evolution reaction (HER) and few studies have been conducted on its electrocatalytic activity. Herein, we successfully fabricate NixS/Cu5FeS4 hybrid catalyst with interface structure between NixS nanoparticles (NPs) and Cu5FeS4 NPs. The NixS/Cu5FeS4 hybrid catalyst exhibits favorable HER performances in 1.0 M KOH electrolyte and demonstrates smaller overpotential and lower Tafel slope than bare NixS NPs and Cu5FeS4 NPs. The remarkable HER performances are attributed to the strongly coupling interface structure between NixS NPs and Cu5FeS4 NPs, which leads to synergistic effect optimizing the HER activity and enhancing the charge transfer during catalytic process. This work provides a promising strategy for the construction of Cu5FeS4-based hybrid catalyst and its application in energy systems.