The preparation of coupled SnO2/TiO2 photocatalyst by ball milling

The coupled photocatalyst SnO2/TiO2 is prepared by ball milling through doping SnO2 into TiO2 and using H2O solution as disperser. The coupled photocatalyst SnO2/TiO2 is characterized by the UV–vis diffuse reflection spectroscopy, X-ray photoelectron spectroscopy (XPS), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The results show that the optimum percentage of SnO2 doped is 5 wt.% and that the photocatalytic activity of the coupled SnO2/TiO2 photocatalyst is much higher than that of TiO2 and SnO2–TiO2 without ball milling. Compared with TiO2, the photoexcited wavelength range of the coupled SnO2/TiO2 red shifts of about 20 nm and the light absorption intensity is also improved. The crystal phase of TiO2 is not changed and new crystal phases are not found by ball milling. SnO2 and TiO2 coupled highly, forming the SnO2/TiO2 photocatalyst. The increased photocatalytic activity of the coupled photocatalyst may be attributed to the enhance charge separation efficiency and extend the wavelength range of photoexcitation.