Decomposition of the molecular precursor Bu4Sn6S6 on the surface of TiO2 to prepare semiconductor composite photocatalysts

In this work, the single source organometallic precursor Bu4Sn6S6 was impregnated and decomposed on the surface of TiO2 to produce semiconductor composites. 119Sn Mössbauer, Raman and ultra violet/visible spectroscopies, powder X-ray diffraction, temperature programmed reduction and surface area suggest for Sn contents of 1, 5 and 10 wt%, the formation of a highly dispersed unstable SnS phase which is readily oxidized by air at room temperature to form SnO2 on the TiO2 surface. The composite with Sn 30 wt% produced a mixture with the phases SnS/γ-Sn2S3 and SnO2. Photocatalytic experiments with the composites SnXn/TiO2 using the textile dye Drimaren red as a probe molecule showed a first-order reaction with rate constants kabsorbance for the composites with Sn 1 and 5% higher than pure TiO2 which was explained by the formation of the more active photocatalyst composite SnO2/TiO2.