摘要
采用溶胶-乳化-凝胶法制备纯TiO2和Fe-TiO2复合体,通过热重-差热分析,X射线衍射和扫描电子显微镜对其热处理过程进行表征,通过晶粒生长动力和热分解反应分析,探讨了铁离子掺杂对TiO2晶粒生长和晶型转变的影响。结果表明:铁离子的掺杂使得TiO2在低温条件下的晶化过程加快,晶粒生长速度增大,晶型转变温度升高。其原因是纯TiO2和Fe-TiO2的晶粒生长表观活化能依次为25.179kJ/mol和27.431kJ/mol;热分解活化能分别为13.743kJ/mol和9.024kJ/mol。Fe对TiO2晶粒生长的阻遏作用和热分解活性增大。
Pure titana (TiO2) and iron-doped TiO2 composites were prepared by a sol-emulsification-gel method.The thermal treatment process of the prepared samples was investigated by themogravimetric-differential thermal analysis,X-ray diffraction and scanning electron microscopy.The effects of doping Fe ions on the crystallite growth and phase transform of TiO2 were discussed by means of the crystalline growth kinetics and the thermal decomposion reaction.The results indicate that the crystallization process and the growing speed of crystalline after the Fe ions doping are enhanced at a low temperature.In addition,the phase-transformation temperature of TiO2 can be increased by Fe ions doping.These are attributed to the difference of the apparent activity energy of the crystalline growth and the activation energy of thermal decomposition between the TiO2 and the Fe-TiO2 films.The Fe ions appear a baffling effect on the TiO2 crystalline growth,resulting in the easy occurrence of TiO2 decomposition.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2010年第1期137-142,共6页
Journal of The Chinese Ceramic Society
基金
湖南省自然基金(2009JJ6101)资助项目