ZnS microsphere/g-C3N4 nanocomposite photo-catalyst with greatly enhanced visible light performance for hydrogen evolution: synthesis and synergistic mechanism study

In this work, ZnS microsphere/g-C3N4 nanocomposites with different ZnS contents were synthesized by a facile precipitation route and characterized by a variety of techniques. The TEM results confirmed that ZnS microspheres are deposited on the surface of g-C3N4 nanosheets with intimate contact in the nanocomposites. Such type-II heterostructures formed between ZnS and g-C3N4 can unexpectedly improve the photocatalytic H2-production rate of g-C3N4 under visible light, which reaches an optimal value of up to 194 mu mol h-1 g-1 at the ZnS content of 50 wt%. The synergistic effect of ZnS and g-C3N4 was proposed to be responsible for the efficient separation of the photogenerated charge carriers and, consequently, the enhancement of the visible light photocatalytic H2 production activity of the nanocomposites. This work highlights that the integration of g-C3N4 and ZnS will be an opportunity to obtain a g-C3N4-based nanocomposite photocatalyst with enhanced photocatalytic H2 production activity, and we hope our work may be helpful for the construction of photocatalysts with efficient visible light H2-production activities.