Influence of doping the nanosized SiO2 powder on structure and activity of photocatalytic films
SiO2纳米粉掺杂对薄膜光催化剂结构和活性的影响

Regard to the poor adsorbability of the fixing film photocatalyst,a new TiO2 thin film by doping the nanosized SiO2 powder with large specific surface area into sol for coating film was prepared.Accoring to the results of characterization by XRD,SEM,FTIR techniques,it was found that the films were mainly anatase structrue,containing a little rutile and its mean crystallite size was about 27nm.And doped SiO2 was dispersed into films forming the amorphous cluster with the size form more than ten nanometers to scores of nanometers.The doping of SiO2 had no effect on the crystal structure and the surficial group of TiO2,except for increassing specific surface area.The result of photocatalytic degradation showed that activity of the film doped by SiO2 largely increased and was greatly influenced by the size and amount of doped SiO2.Besides,this photocatalyst also had very good stability.During the course of continuous experiment for more than 30 days,removal efficiency of reactive brilliant red X-3B was kept at about 80% all the time.