Controlled strategy to synthesize SnO2 decorated SnS2 nanosheets with enhanced visible light photocatalytic activity

Abstract

Novel SnO₂ nanoparticle-decorated SnS₂ nanosheets were synthesized via a one-pot solvothermal process using SnCl₄·5H₂O and CH₄N₂S as precursors. SnS₂@SnO₂ nanosheets were characterized by XRD, TEM, FESEM, XPS and UV-vis diffuse reflectance spectra (DRS). The band-gap of SnO₂@SnS₂ can be easily tuned by the controlled experimental strategy. Anisole and ethanol with different volume ratios were used as binary solvent to tune the composition of SnS₂@SnO₂ nanocomposites (NCs) continuously and the composites gradually change from hexagonal SnS₂ into tetragonal SnO₂. All of the SnS₂@SnO₂ nanosheets exhibited enhanced visible light photocatalytic activity, which was remarkably superior to SnS₂, SnO₂ and Degussa P-25. The obtained SnS₂@SnO₂ NCs with V_ethanol/V_anisole = 1 : 2 showed the best photocatalytic capability. Furthermore, the formation mechanism of SnS₂@SnO₂ nanosheets has also been discussed.