Abstract: TiO2 was semiconductor and widely applied in the fields of catalysis,sensing,hydrogen generation,optics and optoelectronics,benefited from its many advantages such as chemical stability,green to environment and low toxicity,etc.However,On the one hand,TiO2 only can be excited by UV,on the other hand,the rapid recombination of electron-hole (e-—h+) pairs after excitation that leading to decrease of catalytic activity and quantum efficiency.The latest research progress on four main modification methods of TiO2 including surface deposition of noble metal,semiconductor composite,ion doping and dye sensitization was introduced respectively.These all methods were aimed to make full use of the sunlight,or to induce crystal surface defects to restrain the recombination of electron-hole pairs.Finally,the modification of TiO2 photocatalyst in the future was predicted.
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