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采用溶胶-凝胶法低温制备了Ti_(1-x)Fe_xO_2纳米晶。利用X射线衍射仪、透射电子显微镜、红外光谱、X射线光电子能谱对样品进行了表征。透射电镜结果表明Ti_(1-x)Fe_xO_2纳米晶的形貌呈颗粒状。TiO_2,Ti_(0.9)Fe_(0.1)O_2,Ti_(0.75)Fe_(0.25)O_2纳米晶的平均粒径分别为3·5,3·0,2·8nm。XRD结果表明随着Fe~(3+)离子掺杂浓度增加,对应于TiO_2(101)晶面的半高宽增大,表明Fe~(3+)离子的掺杂促使TiO_2晶格扭曲。Ti_(1-x)Fe_xO_2纳米晶为TiO_2锐钛矿相。XPS结果表明Ti_(1-x)Fe_xO_2纳米晶中Ti的价态为4+,Fe的价态为3+。与纯TiO_2红外光谱相比,Ti_(1-x)Fe_xO_2红外光谱中TiO_2表面与缔合的-OH伸缩振动和弯曲振动的吸收均发生J蓝移,表明Fe~(3+)TiO_2之间的化学键作用。Ti-O-Ti伸缩振动吸收蓝移是由Fe-O-Ti伸缩振动引起的,表明Fe~(3+)离子掺入TiO_2晶格并占据了晶格Ti~(4+)的位置。Ti_(1-x)Fe_xO_2纳米晶溶胶-凝胶法低温制备的机理也进行了研究。
Ti_ (1-x) Fe_xO_2 nanocrystals were prepared by sol-gel method at low temperature. The samples were characterized by X-ray diffraction, transmission electron microscopy, infrared spectroscopy and X-ray photoelectron spectroscopy. The results of TEM showed that the morphology of Ti_ (1-x) Fe_xO_2 nanocrystals was grainy. The average particle size of TiO_2, Ti_ (0.9) Fe_ (0.1) O_2 and Ti_ (0.75) Fe_ (0.25) O_2 nanocrystals were 3.5, 3.0 and 2.8 nm, respectively. The XRD results show that the FWHM of the TiO 2 (101) crystal plane increases with the doping concentration of Fe 3+ ions, indicating that the doping of Fe 3+ ions causes the lattice distortion of TiO 2. Ti_ (1-x) Fe_xO_2 nanocrystals are TiO_2 anatase phase. The results of XPS show that the valence of Ti is 4 + and the valence of Fe is 3+ in Ti_ (1-x) Fe_xO_2 nanocrystals. Compared with the pure TiO_2, the blue shift of the absorption and absorption of the -OH stretching vibration and bending vibration of the TiO_2 surface in the Ti_ (1-x) Fe_xO_2 infrared spectrum was observed, indicating that the Chemical bond effect. The blue shift of Ti-O-Ti stretching vibration is caused by the stretching vibration of Fe-O-Ti, which implies that Fe 3+ ions occupy the lattice of Ti 4+. The mechanism of low temperature preparation of Ti_ (1-x) Fe_xO_2 nanocrystalline sol-gel method was also studied.