| Abstract: The Lanthan ide doped TiO2 photocatalysts were prepared by the sol-gel and impregnation method, denoted as RE/TiO2(RE=La, Y, Gd, Er, Nd, Pr). FTIR, XRD, TEM, Low temperature adsorption/desorption, TG/DTA, UV-Vis diffuse reflectance spectroscopy(DRS) and surface photovoltage spectroscopy (SPS) were used to characterize TiO2 and RE/TiO2. The photocatalytic degradation of C2H4 and CH3Br was used as a probe reaction to evaluate their photocatalytic activities. The relationship of spectroscopic properties and gas-phase photocatalytic performance of TiO2 and RE/TiO2 was discussed. The results indicated that RE/TiO2 catalysts had higher content of anatase, smaller particle sizes , higher specific surface area and lager band gap than those of pure TiO2. In addition, La3+, Y3+, Gd3+, Er3+, Nd3+doped TiO2 had stronger photovoltage signals and higher photocatalytic activities as compared with pure TiO2. However Pr3+doped TiO2 had lower photocatalytic activity responding to the lower photovoltage signal. The higher photocatalytic activities may be mostly attributed to the effective separation of photo-generated electron-hole pairs. |
