论文部分内容阅读
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。
TiO2 nano - powder was prepared by sol - gel method. On the dry gel made DTA, TG and other thermal analysis. XRD microstructure data were used to analyze the growth behavior and phase translocation of the powder crystal. The results show that when the heat treatment temperature is below 500 ℃, the particle size of the powder grows slowly. When the heat treatment temperature is above 500 ℃, the powder grows rapidly. The phase transformation theory was used to calculate the activation energy of grain growth and the activation energy of phase translocation. The results show that the activation energy of particle growth in high temperature is several times higher than that in low temperature (below 50 ℃) Of the anatase to rutile phase activation energy is much lower.