Preparation And Photocatalytic Property Of Iron-doped And Mesoporous TiO₂

Titanium dioxide is a kind of important semiconductor photocatalysis material and it has many advantages, such as high activity, anti-photochemical and chemical erosion, well stability, correspondingly low price and intoxicity. Many organic molecules will be photo-degraded completely by photo-catalyst TiO₂, so it has offered conciderable potential for wide use in many fields such as prevention and cure to environment pollution, water treat with, air purifying, the prepartion of self-cleansing materials. As more attention is payed to environmental protection, photocatalysis material TiO₂ has been focus on material science and catalysis ology. But TiO₂ is a wideband semiconductor, and it is excited only by ultraviolet light resource (wavelength lower than 388nm). Ultraviolet light possesses 5% in the whole sunlight, which leads to low utilization rate of photos and limited application. For the sake of widening spectral response range of TiO₂ and enhancing the utilization rate of sun's rays, a lot of work has been done. People put forward to many modified methods, including the sensitization with organic dye, deposition with notable metal, and complex of semiconductor with Sol-gel method. But above methods have some disadvantages of poor stability, high cost and complicated synthesizing technics. In order to offset these shortages, woke below was done in this paper:Firstly, the technics of transitional metal ions doping was designed in my research work. The synthesis methods of doped TiO₂ were probed in the first instance. Taking simple and low-cost inorganic salts as raw materials, nanometer-sized TiO₂ powdes modified with iron ions doping were prepared by nomal pressure lipuid-phase method and microwave lipuid-phase method respectively. Then powdes synthesized by the two methods were characterized. XRD analysis showed that they had anatase structure. The powders are less aggregation and symmetrically ball-like through TEM analysis and particle size is about 20 nm. The applying experiment testified that modified TiO₂ had higher reaction activity and velocity and efficiency of degration towards organic dyes.Secondly, mesoporous TiO₂ with iron doping was researched in this ariticle. It is well known that nano-TiO₂ has high activity as a photo-catalyst, but pore structure is not possessed in these particles. Mesoporous materias with pore diameters in the range of 2～50 nm, have high specific surface areas, large pore volumes and narrow pore size distributions, thereby offering conciderable potential for wide use in the fields of catalysis, absorption and separation. They...