摘要
用溶胶 -凝胶法制备了TiO2 纳米粉晶。对干凝胶做了DTA、TG等热分析。利用XRD微结构数据对粉晶长大行为及其相转位进行了分析研究。结果表明 ,当热处理温度低于50 0℃时 ,粉末粒径增长缓慢 ,而热处理温度高于 50 0℃时 ,粉末生长迅速。运用相变理论计算了晶粒长大激活能及相转位活化能 ,研究表明 ,高温区粒子生长激活能比低温区 (50 0℃以下 )高出几倍 ;与粗晶粒相比 ,TiO2 的锐钛矿向金红石相转变的活化能要低很多。
Nanocrystalline TiO 2 powder was prepared by sol-gel process.The structures of the TiO 2 powder annealed at different temperatures were studied by thermogravimetric analyzer (TG),differential thermal analysis (DTA),X-ray diffraction (XRD).The powder grown behavior and phase transformation were studied by XRD microstructure data and the phase transformation theory.The results showed that the powder particle-size grown very slow at low annealing temperature (<500℃),while the annealing temperature was higher than 500℃ the powder grown very fast. The particle growing activation energy and the phase transformation activation energy were also studied by phase transfromation theory.The results showed that the particle growing activation energy of high temperatures region (>500℃) were much higher than the activation energy of low temperatures region,and compared with the raw crystalline TiO 2,nanocrystalline TiO 2 possessed very low phase transformation activation energy.
出处
《功能材料》
EI
CAS
CSCD
北大核心
2000年第2期186-188,共3页
Journal of Functional Materials
基金
广州市科委重点项目资助
