Bi2S3-ZnS/graphene complexes: Synthesis, characterization, and photoactivity for the decolorization of dyes under visible light

A series of Bi2S3-ZnS/graphene photocatalysts were prepared using a facile and efficient solvothermal method. The obtained products were characterized by X-ray powder diffraction (XRD), UV-vis absorption spectroscopy (UV-vis), X-ray photoemission spectroscopy (XPS), and Brunauer-Emmett-Teller surface area analysis (BET). The morphology and microstructure of the as-prepared hybrid were characterized by Scanning electron microscopy (SEM) and Transmission electron microscopy (TEM) images. It was revealed that the graphene sheets were inagauze-like morphology, and the Bi2S3-ZnS nanorods assembled into anechinus structure and attached onto the graphene sheets. Bi2S3-ZnS/graphene photocatalysts showed high photocatalytic activity during the degradation of Rhodamine B (Rh. B) and methylene blue (MB) under visible-light irradiation (lambda >= 400 nm). The as-prepared Bi2S3-ZnS/graphene photocatalysts exhibit wide absorption in the visible-light region and display superior visible-light-driven photocatalytic activities in degradation of Rh. B and MB compared with pristine ZnS/graphene microspheres. Incorporation of Bi3+ into ZnS/graphene had shown noteworthy effects on the development of photocatalytic activity. The dramatic enhancement in the visible light photocatalytic performance of the Bi2S3-ZnS/graphene composites could be attributed to the effective electron-hole separations at the interfaces of the two semiconductors, which facilitate the transfer of the photoinduced carriers. The present study provides helpful insight into the design of novel and highly efficient sulfate heterostructure photocatalysts. Thus, the Bi2S3-ZnS/graphene hybrid is expected to be effective photocatalysts. Published by Elsevier Ltd.