Shape, size and photocatalytic activity control of TiO2 nanoparticles with surfactants

Shape-, size- and photocatalytic activity-controlled TiO2 nanoparticles were prepared from Ti(OBu)4 and TiCl4 through the sol–gel method and studied for photocatalytic decomposition of methyl orange in fixed film batch reactors. The results showed that shape and size of TiO2 nanoparticles could be manipulated by the use of surfactants during preparation. Spherical, cubic, ellipse nanoparticles and nanorods of TiO2 were obtained with different surfactants. Shape- and size-controlled TiO2 nanoparticles showed a red shift in UV–vis light reflectance spectra, which would be beneficial for photocatalytic reactions, as compared to TiO2 nanoparticles obtained without the use of surfactants. TiO2 nanoparticles with different shapes and sizes showed different photocatalytic activities. Cubic nanoparticles prepared with the use of sodium dodecyl sulfate had a higher photocatalytic activity than other TiO2 nanoparticles.