Preparation of Doping Nano-TiO2 by Impregnation Method and Study on Its Photocatalytic Performance for Organic Pollutants

The research objectives of the study are to manufacture nano-TiO₂ with doping Fe³⁺, Ce³⁺ and La³⁺ adopting impregnation method, examine the effects of the preparing condition on catalyst performance, and explore the influence of the adding account of metal ions and different ion-combinations on the photocatalytic activity of modified nano-TiO₂. The experiment results support the following three conclusions. Firstly, the optimum condition for the preparation of doping nano-TiO₂ using impregnation method are stirring the solution with the speed of 200r/min for 2 hours at the temperature of 20°C and pH value of 6, drying the solution slowly so as to get solid residue, and roasting the residue for 2 hours at the temperature of 650°C. Secondly, metal ions addition using impregnation method can improve the photocatalytic activity of nano-TiO₂ obviously. The optimum concentrations for mixing Fe³⁺, Ce³⁺ and La³⁺ are 2.7%wt, 0.65%wt and 0.36%wt respectively. The ranking of photocatalytic activity of modified nano-TiO₂ is 0.35%wtLa³⁺ 1^st, 0.65wt%Ce³⁺ 2^nd, and 2.7wt%Fe³⁺ 3^rd. Thirdly, The photocatalytic activities of multi-constituent doping nano-TiO2 present the below orders: (1).Fe³⁺ + La³⁺> Fe³⁺ + Ce³⁺> Fe³⁺; (2).Ce³⁺ + La³⁺ > Ce³⁺ + La³⁺; (3).the catalyzing activity of the combination of Fe³⁺, Ce³⁺ and plus La³⁺ is lower than any of individual ion addition.