Amorphous RuS ₂ electrocatalyst with optimized active sites for hydrogen evolution

Abstract

Transition metal chalcogenides have attracted much attention as high-performance electrocatalysts for hydrogen evolution reaction (HER). Here, we synthesized an efficient HER electrocatalyst of amorphous ruthenium sulfide (A-RuS₂), exhibiting an overpotential of 141 mV at the current density of 10 mA cm^-2 and a Tafel slope of 65.6 mV dec^-1. Experiments demonstrate amorphous RuS₂ has much better catalytic activity than that of its crystalline counterparts. Our study shows that amorphous RuS₂ has increased intrinsic activity and active sites. This work provides a feasible strategy for the development of HER electrocatalysts in amorphous state.