Hollow CdS-ZnS-ZIF-8 Polyhedron for Visible Light-Induced Cr(VI) Reduction.

By loading a small amount of cadmium acetate dihydrate on the zeolitic imidazolate framework-8 (ZIF-8), a hollow CdS-ZnS-ZIF-8 composite was facilely synthesized by rapid solid-phase grinding with thioacetamide. The evolution of the structure, composition, and photoelectrochemical properties was studied by a series of methods. When it was used as a photocatalyst, the hollow CdS-ZnS-ZIF-8 composite demonstrated a highly visible light response as well as a robust ability and reusability for Cr(VI) reduction, which could be ascribed to the hollow structure and ultrasmall CdS nanoparticles. Notably, the presence of ZIF-8-S (ZIF-8 ground with thioacetamide) could also obviously enhance the stability of CdS by promoting the separation of the photogenerated charge during light irradiation.