ZnS microsphere/g-C3N4 nanocomposite photocatalyst 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 H-2-production rate of g-C3N4 under visible light, which reaches an optimal value of up to 194 mmol 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 H-2 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 H-2 production activity, and we hope our work may be helpful for the construction of photocatalysts with efficient visible light H-2-production activities.