Preparation of Sb₂O₃-doped TiO₂ by hydrothermal method and the inhibition of photocatalytic activity

Two kinds of Sb₂O₃-doped TiO₂ (Sb₂O₃ : TiO₂ = 0-0.35 mol%) nano-particles were synthesized by the hydrothermal method at 200°C for 6 h. The first kind of Sb₂O₃-doped TiO₂ was prepared by using titania and antimony trichloride as reactants. The second kind of Sb₂O₃-doped TiO₂ was prepared by using metatitanic acid and antimony trichloride as reactants. The Sb₂ O₃-doped TiO₂ powders were characterized by XRD, SEM, EDS, TG, IR and the diameter of the particles was evaluated by Scherrer equation. EDS characterization shows that Sb₂O₃ exists in Sb₂O₃-doped TiO₂. The crystallines of all samples are anatase in XRD patterns. The dopant of Sb₂O₃ can inhibit the particle growth of the second kind of Sb₂O₃-doped TiO₂ when the crystalline is changed into anatase TiO₂. The photocatalytic activities of the two kinds of Sb₂O₃-doped TiO₂ were characterized by photodegradation of rhodamine B. The photocatalytic activity of Sb₂O₃-doped TiO₂ is effectively suppressed by the doping of Sb₂O₃. When Sb₂O₃ : TiO₂ is 0.21%, the photocatalytic activity of Sb₂O₃-doped TiO₂ is the lowest. The photocatalytic activity of the second kind of Sb₂ O₃-doped TiO₂ is lower than that of the first.