LAUSR

Abstract TiO 2 /SnO 2 nanocomposites have been prepared by laser pyrolysis of volatile TiCl 4 and SnCl 4 precursors introduced together or separately in the reaction zone in the presence of air as oxidant and ethylene as sensitizer. Prior to the obtaining of TiO 2 /SnO 2 nanocomposites with the different Sn concentrations (1.1–4.8 at.%), the best experimental conditions were identified for preparing pure anatase phase TiO 2 samples considered as photoactive reference sample. The TiO 2 /SnO 2 composites were characterized using X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM), and UV–vis diffuse reflectance spectroscopy (DRS) techniques. The structural results show the presence of both TiO 2 main phases: anatase (65–82% − the majority one) and rutile, as well as of small amounts of SnO 2 tetragonal phase, all those with mean crystallite dimensions in the 8–22 nm range. Laser synthesized TiO 2 /SnO 2 samples have a lower band gap energy and some of them (containing 1.8 or 4.8 at.% Sn) show higher photoactivity in the process of Methyl Orange solutions UV discoloration when compared with the P25 Degussa commercial sample.