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本文结合透射电镜分析研究了 sol-gel方法制备的纯二氧化钛和掺铁二氧化钛干凝胶的晶化过程。计算了在不同的煅烧温度下二氧化钛微晶的晶胞参数，晶粒度，畸变等参数的变化关系。应用非晶物质晶化晶核生长速率方程计算的晶粒生长活化能表明晶粒生长分为两个阶段，临界点大约为相变温度。纯的和掺铁的二氧化钛在两个阶段的晶粒生长活化能分别约为 20.8kJ· mol-1,70.9kJ· mol-1和 26.6kJ· mol-1,78.8kJ· mol-1。这个差别可能是由于相变过程首先发生在小晶粒上，导致小晶粒生长较为困难所致。
In this paper, the crystallization process of pure titanium dioxide and iron-doped titanium dioxide xerogel prepared by sol-gel method was studied by transmission electron microscopy. The relationship between the cell parameters, grain size, distortion and other parameters of the titania crystallites at different calcination temperatures was calculated. The activation energy of grain growth calculated by using the equation of crystal growth rate of amorphous material nucleation shows that the grain growth is divided into two stages, and the critical point is about the phase transition temperature. The activation energies of pure and iron-doped titania in two stages are about 20.8kJ · mol-1, 70.9kJ · mol-1 and 26.6kJ · mol-1,78kJ · mol-1, respectively. This difference may be due to the fact that the phase transformation first occurs on small grains, which makes it difficult to grow small grains.