Synthesis of layer-like Ni(OH)2 decorated ZnIn2S4 sub-microspheres with enhanced visible-light photocatalytic hydrogen production activity

Novel layer-like Ni(OH)(2) co-catalyst-decorated ZnIn2S4 microsphere photocatalysts were synthesized for the first time via a facile in situ deposition method to boost the photocatalytic H-2-production performance. The physical and optical properties of the as-prepared Ni(OH)(2)-ZnIn2S4 composite samples were characterized via X-ray diffraction (XRD), transmission electron microscopy (TEM), UV-vis diffusion reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS), and surface photovoltage spectroscopy (SPV). The results indicate that the photocatalytic H-2 evolution activity of the ZnIn2S4 microspheres under visible light irradiation significantly enhances by introducing inexpensive Ni(OH)(2) as a cocatalyst. The 5 mol% Ni(OH)(2)-ZnIn2S4 sample shows the highest H-2-production rate of 8.35 mmol g(-1) h(-1), which is 18 times higher than that of pure ZnIn2S4. Moreover, photocatalytic activity of the Ni(OH)(2)-ZnIn2S4 sample remains stable even after 4 cycling photocatalytic experiments. In addition, a possible mechanism on the enhanced photocatalytic activity was proposed and verified by surface photovoltage spectroscopy.