In Situ Synthesis of Conjugated Polyvinyl Alcohol Derivative-Modified SnS2 Nanosheets with Improved Visible Photocatalytic Reduction of Cr(VI)

The development of high-performance photocatalysts is crucial in addressing water environmental pollution using photocatalytic technology. In this study, CPVA/SnS2 heterojunctions modified with conjugated polyvinyl alcohol were prepared using water-soluble polyvinyl alcohol. The effects of temperature and CPVA loading amount on the chemical composition, morphology, optical and electrochemical properties, and visible-light photocatalytic reduction of aqueous Cr(VI) performance of CPVA/SnS2 were evaluated. The results showed that the CPVA was uniformly coated on the surface of SnS2, improving the light absorption range and the effective utilization of photogenerated carriers. All CPVA/SnS2 heterojunctions exhibited enhanced photocatalytic activity compared to bare SnS2. The reaction rate for the photocatalytic reduction of Cr(VI) by CPVA/SnS2-B (0.034 min(-1)) was 3.46 times higher than that of SnS2 (0.0098 min(-1)). The photocatalytic mechanism of S-scheme heterojunction for the photocatalytic reduction of Cr(VI) by CPVA/SnS2 was proposed based on the trapping experiments and electrochemical results. This study provides a straightforward strategy for the construction of efficient photocatalysts.