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采用溶胶-凝胶法制备了不同含量铁掺杂的纳米TiO2粉末,利用X射线衍射、X射线光电子能谱和紫外可见光谱技术对粉末的晶体结构和光吸收性能进行了表征。Fe/TiO2粉末中铁主要以Fe2O3存在,与TiO2形成了钛铁固溶体。TiO2的晶粒尺寸和相转变受焙烧温度的影响较大,焙烧温度越高,晶粒尺寸越大。铁掺杂后TiO2粉末的晶粒尺寸随焙烧温度升高的增大速度减慢。掺铁量越多,平均晶粒尺寸越小。铁掺杂后TiO2粉末的光谱吸收范围被明显拓展至可见光区,可以被较宽范围的可见光激发。光催化反应快慢与入射光波长有关,紫外光下Fe/TiO2粉末对甲基橙的光催化降解活性与纯TiO2粉末相比较差,而在可见光下,Fe/TiO2粉末对甲基橙的光催化降解活性明显好于纯TiO2粉末。
The nano-TiO2 powders with different iron doping content were prepared by sol-gel method. The crystal structure and optical absorption properties of the powders were characterized by X-ray diffraction, X-ray photoelectron spectroscopy and UV-Vis spectroscopy. Iron in the Fe / TiO2 powder mainly exists as Fe2O3, forming an iron-titanium solid solution with TiO2. The grain size and phase transition of TiO2 are greatly affected by the calcination temperature. The higher the calcination temperature, the larger the grain size. After iron doping, the grain size of TiO2 powder slowed down with the increase of calcination temperature. The more the iron content, the smaller the average grain size. After iron doping TiO2 powder spectral absorption range was significantly extended to the visible region, can be a wide range of visible light excitation. The photocatalytic reaction speed is related to the wavelength of incident light. The photocatalytic degradation of methyl orange by Fe / TiO2 powder under UV light is worse than that of pure TiO2 powder. Under visible light, the photocatalytic activity of Fe / TiO2 powder on methyl orange Degradation activity was significantly better than pure TiO2 powder.