Stainless Steel Mesh-Supported NiS Nanosheet Array as Highly Efficient Catalyst for Oxygen Evolution Reaction

Nickel(II) sulfide (NiS) nanosheets with a thickness of 10 nm and a size of 200 nm were facilely grown on stainless steel (SLS) meshes via a one-pot hydrothermal method. This unique construction renders an excellent electrical contact between the porous film of active NiS sheets and the highly conductive substrate, which exhibits a superior catalytic activity toward oxygen evolution reaction (OER). The NiS@SLS electrocatalyst exhibits an unusually low over-potential of 297 mV (i.e., 1.524 V vs RHE) at a current density of 11 mA.cm(-2), and an extra small Tafel slope of only 47 mV.dec(-1) proves an even more competitive performance at high to very high current densities. This performance compares very favorably to other Ni-based catalysts and even to the precious state-of-the-art IrO2 or RuO2 catalyst.