Efficient ZnO1-xSx composites from the Zn5(CO3)2(OH)6 precursor for the H2 production by photocatalysis

ZnO1-xSx (x = 0.2, 0.5, 0.7, and 1.0) composites were prepared from the hydrozincite precursor (Zn-5(CO3)(2)(OH)(6)) as Zn source by sulfidation during the solvothermal treatment using thiourea as sulfur source at different molar ratio. The sulfurized composites were characterized by XRD, FTIR, TGA, SEM-EDS, N-2 physisorption, UV-vis diffuse reflectance spectroscopy, and photoluminescence. Additionally, photocatalysts were deposited onto ITO coated supports to perform their photoelectrochemical characterization. The sulfurized samples were composed of cubic-ZnO and cubic-ZnS with proportions close to the theoretical ones, given a ZnO1-xSx, heterostructures. Mesoporous composites with large specific surface area (up to 207 m(2) g(-1)) were obtained. All the obtained composites were evaluated in the production of H-2 from a MetOH-water solution and UV light. The photocatalytic stability of the best composite was also evaluated for five reaction cycles. The photocatalytic properties of the ZnO1-xSx composite is explained as a function of the generation capacity of electron-hole pairs when the photocalyst is illuminated jointly with the charge transfer resistance of photocatalysts in a methanol-water solution. (C) 2017 Elsevier Ltd. All rights reserved.