Photocatalytic hydrogen production by stainless steel@ZnS core–shell wire mesh photocatalyst from saltwater

Ni-doped stainless steel@ZnS core–shell wire mesh photocatalyst for photocatalytic hydrogen production was prepared by a solvothermal method. Effects of wire mesh density, doping, and surface texture on the photocatalytic activity were studied. The photocatalytic activity of the catalyst was evaluated by splitting Na2S/Na2SO3 solution into H2. The effects of surface texture and doping on the surface wettability and photocatalytic activity were investigated. Energy-dispersive X-ray spectroscopy (EDX) analysis and Ni mapping images indicated that a small amount of Ni is loaded on the ZnS. The highest hydrogen evolution is obtained for the Ni-doped core–shell photocatalyst when ZnS is grown on wire mesh substrate (distance between adjacent wires = 60 μm) with precursor solution (Ni(CH3COO)2/Zn(CH3COO)2 = 1%) by a solvothermal reaction for 0.5 h. The enhanced performance results from enhanced separation of the photoinduced carriers by Ni-doping, and effective contact among sacrificial aqueous solution and the ZnS shell. Photocatalytic activity and photocurrent of three repeated tests of recycled photocatalysts were also investigated.