Copper and cobalt co-doped Ni3S2 grown on nickel foam for highly efficient oxygen evolution reaction

Abstract Multi metal-based elctrocatalyst may provide the more active sties, optimal synergistic effect and unique nanostructure for efficient oxygen evolution reaction (OER). Here, we report the efficient OER performance of copper and cobalt co-doped Ni3S2 supported on nickle foam (CuCo-Ni3S2/NF). The nanoparticles of Ni3S2 grown on NF are synthesized by simple hydrothermal method and liquid phase vulcanization method. Direct hydrothermal growth results in a strong bonding between CuCo-Ni3S2 and the substrate, which has strong electrical conductivity and long-term stability. The different ratio of copper to cobalt doping has been investigated. The optimized CuCo-Ni3S2/NF (1:1 of molar ratio of copper to cobalt) demonstrates superior catalytic activity to OER in 1.0 M KOH with the lowest overpotential of 400 mV at a current density of 100 mA cm−2. CuCo-Ni3S2/NF has the largest electrochemically active surface area (ECSA) of 513 cm2 and excellent conductivity. The enhanced mechanisms may be ascribed to the incorporation of copper and the strong electron interaction among copper, cobalt and nickel element. The intrinsic activity of CuCo-Ni3S2/NF may be determined by cobalt and nickel sulfide. This low-cost and efficient electrocatalyst can be used as a promising electrode material for the oxygen evolution reaction.