Effect of Heat Treatment Temperature on Microstructure and Antibacterial Properties of Ag⁺、Zn^2＋ Co-Doped TiO₂ Thin Films

Sol-gel method was used to prepare the Ag+, Zn2+ co-doped TiO2 thin film. Influence of temperature on stability of the Ag-Zn-TiO2 system was studied. XPS, SEM, XRD and antibacterial tests were used to investigated the effect of heat treatment temperature on the chemical composition,microstructure,grain size and antibacterial property of the obtained film. The results show that the doped film was uniform and dense.The white point existed on film surface was Ag2O and the size was about 10 nm, while the Zn2+ took place the Ti4+ into TiO2 lattice.Doped ions could inhibite grain growth of TiO2. The doped film exhibited antibacterial rate of 100% when UV light existed, the value was 99.5% when no light, both of the data were significantly better than that of the non-doped film. With increasing the heat treatment temperature, the antibacterial activity of film increased first and then decreased, the best heat treatment temperature was 500 ℃.