Visible-light-driven SnO2/TiO2 nanotube nanocomposite for textile effluent degradation
Nanocomposite of SnO2/TiO2 nanotube (NT) was prepared by a simple two-step procedure, viz., hydrothermal preparation of TiO2 NT followed by chemical precipitation of SnO2 nanoparticle sensitized TiO2 NT. Transmission electron microscopy analysis revealed that the as-synthesized TiO2 NTs exhibit a diameter of 20–30 nm and a length of 1–2 μm with a wall thickness of 2–5 nm. The particle size of SnO2 nanoparticles in the composite was estimated to be 4–6 nm. Both the TiO2 NT and SnO2/TiO2 NT composite were considered for the photocatalytic degradation of textile dye effluent under UV and sunlight irradiation. The SnO2/TiO2 NT composite showed improved degradation efficiency. Photoluminescence spectra of SnO2/TiO2 NT composites showed a decrease in intensity when compared to the TiO2 NT – revealing that the rate of recombination is reduced in the SnO2/TiO2 NT composite, which is responsible for larger photocatalytic activity. Further, an effluent degradation efficiency of 85% was obtained for the SnO2/TiO2 NT composite under sunlight irradiation and this can be considered as one of the best values achieved so far.