Photocatalytic Mechanism of Nano-TiO_2 and Analysis on Factors Influencing Its Photocatalytic Activity
Wang Jisena,Feng Zhongbina,Sun Jinquanb,Jia Mingjiana,Song Zhenleia (a. College of Mechanical Engineering;b. College of Materials Engineering,Shandong University of Science and Technology,Qingdao 266510,China)
The reseach development of TiO2 photocatalysis technology was presented, and the mechanism of photocatalytic activity of nano-TiO2 was analyzed. Primary factors affecting the photocatalytic activity of nano-TiO2 were discussed. The smaller crystal grains are, the more effectively they can improve the photocatalytic activity of TiO2. Deposition of noble metals can promote separating efficiency of surface photo-induced current carriers and depress the electron-hole recombination. Coupling of semiconductors is benificial to charge separation and expand the light absorption spectrum of TiO2. Doped metal ions can produce lattice defects in TiO2 by entering into the crystal lattices, thus the photocatalytic property of TiO2 is improved by decreasing the elentron-hole recombination. On the other side, doped nonmetal ions can restrain the conversion of crystal types, improve the light absorption efficiency of the sample, and decrease the recombination of photon-generated carriers, thus the photocatalytic efficiency of nano-TiO2 is increased obviously.
【CateGory Index】： O643.3