Preparation And Photocatalytic Properties Of Ce Doped And Ce-Zn Co-doped Titanium Dioxide Thin Films

In this paper, Ce/TiO₂and Ce-Zn/TiO₂films were prepared on glass substrate bysol-gel process. The effect of process parameters, such as doping level of Ce and Zn, heattreatment temperature and pulling speed on the photocatalytic activity of the films wereinvestigated systematacially. The photocatalytic activity of Ce/TiO₂, Zn/TiO₂andCe-Zn/TiO₂films was investigated under the same conditions. The structure, compositionand crystalline phase transformation of the films were characterized by XRD, DSC, FTIR,AFM and Raman in this experiment. The photocatalytic activity was evaluated by thedegradation rate of methyl orange solution. The optical transmittance of films was studiedby UV-Vis spectrophotometer.The experimental results show that under this experimental condition, the optimumconditions is doping amount Ce1mol%, heat treatment temperature200℃, pulling rate120mm/min in Ce doped experiments, and the degradation rate of this sample for methylorange solution reaches95.03%after uv irradiation50min, while the degradation rate ofthe pure TiO₂for methyl orange is only74.97%under the same conditions; In Ce-Znco-doped experiments, when Ce and Zn atom ratio of1:1, their synergy effect to improvethe photocatalytic activity is the best, and the optimum conditions is heat treatmenttemperature400℃, pulling rate90mm/min, doping amount Ce1.5mol%-Zn1.5mol%, thedegradation rate of this sample for methyl orange solution is99.32%after uv irradiation40min, and the degradation rate of pure TiO₂for methyl orange is only50.4%under thesame conditions; It shows that the Ce-Zn/TiO₂film has the best photocatalytic activityunder the same experimental conditions in the comparative experiments of Ce, Zn singledoped and Ce-Zn co-doped experiments.The doped films prepared in this experiment all consist of anatase, and the averageparticle size of the samples are about10nm; The crystal transformation and grain growthof TiO₂are hindered by Ce, Zn and Ce-Zn doped. The synergy effect of Ce-Zn co-dopedon the promotion of the photocatalytic activity of TiO₂is more obvious. Normally thehydrophilic of the films decreases after increasing firstly with the heat treatmenttemperature increasing. The average transmittance of Ce/TiO₂and Ce-Zn/TiO₂filmsprepared by sol-gel process is above75%with the application prospect of self-cleaning glass.