Preparation Of Ag Doped Nano TiO₂ Films And Its Photocatalytic Property Research

Aiming at the actuality of disadvantages of TiO2 powder, difficult to separate, low using rate of light and easy to deposit and agglomerate, which hold back the transformation of photocatalytic technology into utility, preparation process of nano-sized TiO2 powder and film were studied, and the fixation of TiO2 was solved and firm thin films with nano-crystalline have been prepared by the sol-gel processing using tetrabutyl titanate as a precursor in this paper. Using ultraviolet germicidal lamp as light source, the photocatalytic activities of T1O2 thin film and TiO2 thin film doped with Ag were studied in the 1 0mg/1 methylene orange solution. Factors influencing of the photocatalytic activities of TiO₂ thin film in photodegradation of methylene orange solution such as calcined temperature, the thickness of films, amount of Ag dopants,repeated using times was discussed. The XRD and SEM results of powders and films showed that crystal type, granularity, particle size distribution of TiO2 and the surface modality of thin film.The results showed that TiO2 semi-conductor with nano-crystalline have been prepared by the sol-gel processing using tetrabutyl titanate as a precursor. The reaction condition was easy to control and the process was stable,thus the distribution uniformity can reach molecule level, and highly quality sol and gel can be acquired ,and further obtained the nano-sized particles. Micro-analytic results of XRD,SEM showed that TiO2 prepared in this experiments was anatase, in which was calcined at 350℃ for 1 hour the average size of TiO2 powder and that of TiO2 particles in the film was above 10 nm,distributions of granularity were narrow and particles distribute uniformly. Comparing the different degradation tests of TiO2 thin film and TiO2 thin film doped with Ag at different calcined temperature showed that coated for 3 times TiO2 thin film of which wascalcined at 350 °C for 1 hour and 10mol% Ag doped behaves the best photocatalytic ability, with its degradation ratio reaching above 25%.It indicates that calcined temperature and amount of Ag dopants influece photocatalytic ability of TiO2 thin film.