Co(Ni)–Mo–Sx Chalcogels Films as pH-Universal Electrocatalysts for the H2 Evolution Reaction

Abstract

Here, a simple dipping coating route was applied to synthesize a series of CoMoSx/NiMoSx chalcogel thin film which in situ grown uniformly on the 3D skeleton of Ni foam as electrocatalysts for the hydrogen evolution reaction (HER). We attempt to understand the effect of pH on the kinetics of the HER. As expected, CoMoSx@Ni foam electrocatalyst presents a low overpotential of 118 mV at 10 mA cm−2 and a low Tafel slope of 85 mV dec−1 for HER in alkaline solution and an overpotential of 129 mV at 10 mA cm−2 and a low Tafel slope of 113 mV dec−1 for HER in acidic solution. The long-term performance of CoMoSx-3@Ni foam revealed that there was no obvious decrease in catalytic activity after 5000 cycles in alkaline medium. We are able to synthesize low-cost and pH-universal catalysts for efficient electrocatalytic production of hydrogen. A dipping coating route was applied to synthesize a series of chalcogel films in situ grown on 3D Ni foam skeleton as catalysts for HER. We attempt to understand the effect of pH on the kinetics of HER. CoMoSx as pH-universal catalyst presents a low overpotential and Tafel slope for HER.