Study On Preparation And Photocatalytic Activity Of Titanium Dioxide Thin Film

The preparation of titanium dioxide thin film and the methods of improving photocatalysis activity and the rate of degradating methyl orange were studied in this paper, Fe³⁺/ TiO₂ system were mainly researched, and the reaction mechanisms of Fe³⁺/TiO₂ film and kinetics of photocatalysis degradation were discussed simultaneously.First, Fe³⁺/TiO₂ film was prepared by sol-gel method, the TiO₂ sol was prepared with different doped concentration of Fe³⁺, Glass piece was used as support, dipping-raising method was used to prepare film, the film was obtained after drying. The film was analyzed by XRD, UV, IR etc, then the optimal technics conditions were educed by experiments under the following conditions: Fe(NO₃)₃ mass was 0.2wt%, nitric acid needed was 0.3ml, calcination temperation was 500℃.Second, the paper also studied degradation of methyl orange solution using above Fe³⁺/ TiO₂ film. Influence of different initial concentrations on degradation process was reviewed, the result shows that low initial concentration was propitious to degradation; Influence of different pH on degradation process was reviewed, when pH was 1, decomposition rate was higher than others; Influence of more oxidant on degradation process was reviewed, there was an optimal mete. The optimal technics conditions were educed by orthogonal experiments under the following conditions: initial concentration was 5mg/L, pH was 1, oxidant mass was 0.8ml.Finally, the mechanisms and the kinetics of photocatalysis degradation of methyl orange were discussed, the rate of photocatalysis degradation can be expressed in first-order kinetics model, The rate constant of reaction was connected with initial concentration and pH of methyl orange solution and added oxidants.