Polyoxometalate mediated synthesis of novel multiporous microspheres of ternary Cu-Sn-S chalcogenides with enhanced photocatalytic activities

The introduction of Keggin-type polyoxometalate (POM) K₄SiW₁₂O₄₀ into the solvothermal synthesis system of Cu₃SnS₄ (CTS) led to the formation of a new CTS-POM particle. The structure and composition were characterized by x-ray diffraction, scanning electronic microscopy and transmission electron microscopy. The results revealed that the CTS-POM particles exhibit multiporous microsphere morphology, which was first observed in CTS materials. A possible growing mechanism was proposed based on POM concentration-dependent growth study of the microspheres. The photodegradation of RhB and H₂ production under UV–vis irradiation was done to evaluate the photocatalytic activities of the samples. The results indicated that the as-synthesized CTS-POM exhibited enhanced photodegration of RhB and photocatalytic H₂ generation compared to pure CTS particles, and the content of loaded POM has an important impact on the catalytic activity of CTS-POM. The 5% POM-loaded CTS microspheres reached the best photocatalytic activity in H₂ production. Meanwhile, increased stability of photocatalytic activity of CTS-POM was also observed. (paper)