Preparation And Properties Characterization Of Modified TiO₂and Research On Its Visible-light Photocatalytic Degradation Of Rhodamine B

TiO2is studied widely among all the semiconductors, due to its higher photocatalytic activity,non-toxic side effects, chemical stability, Safety, and cheapness. But TiO2can only be inspired byultraviolet light in sunlight because its larger band-gap (3.2eV for anatase form), thus to lower therates of utilization of solar energy. In addition, the efficiency of photoquantum is low due to therecombination of photo-induced electrons and holes. Based on the above factors, cobalt and tindoped Co-Sn/TiO2photocatalysts was prepared by sol-gel method using tetrabutyl titanate astitanium source, and the Co-Sn/TiO2/SiO2and Co-Sn/TiO2/WO3photocatalysts also be synthesizedrespectively in the study. Meanwhlie, their characteristics were investigated by XRD, FI-IR, UV-visDRS, BET and photocatalytic degradation for Rhodamine B (Rh B).1. In the system of Co-Sn codoped TiO2,all of the synthetic photocatalysts that belongs to thenanoparticle are Rutile. The crystalline phase of the catalyst did not change when the calcinationtemperature rise. And the crystalline size of Co-Sn codoped TiO2is far less than the pure TiO2which shows a certain amount of Co-Sn codoping can inhibit the growth of grain. By Co, Sndoping can narrow the band-gap of TiO2, which broadens the range of TiO2response to visiblelight, but it has no significant contribution to the performance of the samples response to the visiblelight, when the calcination temperature rise. In addition, the study found that10%Sn and1%Co(both are mass percentage) codoped TiO2performed best in the degradation of rhodamine Bunder the visible light irradiation, when the calcination temperature is500℃,and the best catalyticefficiency is73.26%.2.Based on the optimization doping amount and calcination temperature, all theCo-Sn/TiO2/SiO2catalysts is Anatase. And the increase of the SiO2can inhibit the growth of grain.Besides, Co-Sn/TiO2/SiO2catalysts can response to the visible light. According to thephotocatalytic performance test, the results show that the efficency of rhodamine B degradation onCo-Sn/TiO2/SiO2catalysts has been improved obviously by taking a comparation with theCo-Sn/TiO2catalysts. And the efficency of the degradation of rhodamine B under the visible lightirradiation are above90%.3.Based on the optimization doping amount and calcination temperature, all the Co-Sn/TiO2/WO3catalysts is Anatase. And the increase of the WO3can inhibit the growth of grain.Besides, Co-Sn/TiO2/WO3catalysts can response to the visible light. According to thephotocatalytic performance test, the results indicate that relevant Co-Sn/TiO2/WO3catalystperformed best in the degradation of rhodamine B under the visible light irradiation, when the masspercentage of WO3is4%. And the best catalytic efficiency is88.09%.