| TiO2 is one of most widely used nanomaterials due to its outstanding properties such as strong oxidizing ability, stable chemical properties, non-toxic and high catalytic efficiency,and so on. However,due to the wide band gap energy of TiO2, it can only be excited by UV light irradiation. In order to improve the degradation efficiency of TiO2 photocatalyst to various pollutants, it is necessary to broaden the light response area of TiO2 and enhance the light response intensity. In this paper,N-doped TiO2 porous films and TiO2 photocatalyst with different morphologies were prepared respectively. The photocatalytic activity of TiO2 under different light sources was also studied. The specific works are as follows:N-TiO2 photocatalyst was prepared by sol-gel method using ammonia water as nitrogen source, and N-TiO2 was modified with silane coupling agent kh550. The TiO2 paste was prepared by a step by step grinding method using P25, N-TiO2,modified P25 and modified N-TiO2 as the raw materials, respectively, glacial acetic acid and deionized water as the polymerization inhibitor, ethyl cellulose and terpilenol as the binder,then through the process of spin coating and calcination to obtain the three kinds of porous TiO2 films. Photocatalytic degradation of 4-nitrophenol (4-NP)was studied using TiO2 porous films under UV light irradiation. Optimal degradation conditions and TiO2 porous films’ durability were investigated. The results indicated that the photocatalytic performance of modified N-TiO2 porous film was the best in the three kinds of TiO2 porous films. The degradation rate of 10 mg/L of 4-NP solution achieved 90% after 180 min under the condition of pH2 and adsorbed 30 min.The modified N-TiO2 porous film was recycled four times, the fourth degradation rates reached 80% after 180 min.TiO2 with different 3D micro/nanostructures was synthesized by hydrothermal method, using tetrabutyl titanate as the titanium source, CTAB, SDBS and SDS as the surfactants, ethanol, polyols and urea as the additives, respectively. The surface morphology and crystal structure of TiO2 photocatalysts were successfully mediated by selecting different additives or their combinations. In addition, the effects of different TBT contents on the morphology were investigated. Some particular 3D structures were achieved, such as double cone cylinder, flower-like cluster with stalactiform petals, urchin-like sphere with plenty of fine and dense surface nanothorns, and lantern-like hollow sphere. The photocatalytic activity of the samples was tested with RhB solution. Among them, a series of photocatalysts prepared from SDBS show a unique structure and good photocatalytic performance. The anatase-rutile(2.57:1) mixed TiO2 with the urchin-like sphere structure showed the best photocatalytic activity on RhB degradation,resulting in a removal rate of 95%and 83% after 150 min of UV and visible light illumination, respectively.The effect of different single organic solvents and mixed organ,ic solvents on the morphology of TiO2 photocatalyst was investigated by using TBT as Ti source and hydrochloric acid as inhibitor. The results show that the pure rutile 3D urchin-like TiO2was obtained when toluene is used as the solvent, and the photocatalytic activity of the 3D urchin-like TiO2 under different light sources was studied by using RhB solution as the target pollutant. The results show that the pure ratile 3D urchin-like TiO2 exhibits high photocatalytic activity to RhB solution under UV light and visible light irradiation. |
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