Preparation of Sn4+ -Doped TiO2 and Investigation of its Photocatalytic Activity

TiO₂ and Sn⁴⁺-doped TiO₂ were prepared by sol-gel method and characterized by the techniques such as XRD, SEM and DRS. The photocatalytic degradation of methylene blue (MB) in aqueous solution was used as a probe reaction to evaluate their photocatalytic activity. The matrix distortion of TiO₂ increases after Sn⁴⁺ doping and a blue-shift of the absorption profile are clearly observed. The results show that doped Sn⁴⁺ inhibits the phase transformation of TiO₂ from anatase to rutile, decreases the diameter of TiO₂ and significantly enhance the photocatalytic activity of TiO₂. The Sn⁴⁺-doped into TiO₂ exert a synergistic effect on their photocatalytic activity.