SnS2 nanoplates/SnO2 nanotubes composites as efficient visible light-driven photocatalysts for Cr(VI) reduction

Abstract SnS 2 /SnO 2 nanocomposites have been successfully prepared via a hydrothermal method using electrospun SnO 2 nanotubes as both substrates and reactants. The ratios of the nanocomposites are controlled by varying the concentration of thioacetamide during the solvothermal synthesis processes. The as-prepared SnS 2 /SnO 2 nanocomposites exhibit considerable improvement on the photocatalytic activities for the reduction of aqueous Cr(VI) under visible light irradiation. Their photoactivities are also much higher than that of SnS 2 nanoplates and a physical mixture of SnO 2 and SnS 2 . In particular, the SnS 2 /SnO 2 -B sample exhibits the highest photocatalytic activity. After visible light irradiation for 60 min, the reduction rate has reached about 100%. The photoelectrochemical analyses further show that the high photocatalytic activity of the SnS 2 /SnO 2 -B sample can be ascribed to the unique structural features and the intimate interfacial contact between SnS 2 and SnO 2 , which is more effective separation of the photo-generated carriers. Graphical Abstract