Ni-doped ZnS decorated graphene composites with enhanced photocatalytic hydrogen-production performance

This study investigated the abilities of photocatalytic H-2 production by Ni-doped ZnS-graphene composite photocatalysts. Undoped or Ni-doped ZnS was loaded on the surface of graphene to prepare a series of composite photocatalysts. Properties of the photocatalysts were characterized by field-emission scanning electron microscope (PESEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HRTEM), ultraviolet visible diffuse reflectance spectroscopy (DRS), photoinduced current, and photocatalytic hydrogen evolution test. The as-prepared graphene@Ni-doped ZnS nanocomposites are highly active photocatalysts for hydrogen evolution and the highest photocatalytic activity reaches 8683 umol h(-1) g(-1). Effects of introducing graphene, doping, and decorated ZnS on the surface chemistry, crystalline property, optical property, surface morphology, and photocatalytic hydrogen production performance were studied. Ni-doping and decorated ZnS on graphene improved the photocatalytic H-2 production activity because of improved dispersing property, increased surface area, increased absorption, and enhanced transfer of photogenerated electrons. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.