水文结合透射电镜分析研究了so1-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述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·nol-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。%The crystallization and phase transformation of the TiO2 xerogel powders, from amorphous to anatase and from anatase to rutile, were studied by X-ray diffraction and TEM methods. The cell parameters, grain size and lattice strain of TiO2 xerogel powders under various calcinating temperature were calculated. It was found that the crystal growth process had obvious two stages with the turning point at about phase transformation temperature. The activation energies of grain growth were calculated in terms of grain size varying with temperature, 20. 8kJ · mol-1, 70. 9kJ·mol-1 in the case of pure samples and 26. 6kJ·mol-1, 78.8kJ·mol-1 in the case of Fe doping samples. The phase transformation may firstly occur in small grains. The small grains may have difficulties in swallowing the other similar sized grains to make themselves grow.
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