Effect of S2− donors on synthesizing and photocatalytic degrading properties of ZnS/RGO nanocomposite

To synthesize ZnS/RGO nanocomposite via one-step solvothermal method with graphene oxide (GO) aqueous solution as precursor, we selected sodium sulfide and thiourea as S2− donor, respectively, with the aim to evaluate the effect of different S2− sources on the synthesis and degrading properties of the composite. The photocatalytic activity of the nanocomposite was investigated through the photocatalytic degradation of methylene blue in aqueous solution. Results showed that ZnS/RGO nanocomposites were synthesized using both sodium sulfide and thiourea as S2− donor, respectively. Compared to pure ZnS, the nanocomposites exhibited higher photocatalytic activity; furthermore, the nanocomposite prepared with sodium sulfide as the S2− source exhibited much better photocatalytic degradation efficiency than that with thiourea as the S2− source. The surface reaction rate constant of the former was two times higher than that of the latter and was six times higher than that of pure ZnS sample.