溶剂热合成法制备锐钛矿型TiO2溶胶及粉体

PREPARATION OF ANATASE TiO_2 SOL AND POWDER BY SOLVOTHERMAL SYNTHESIS

以钛酸丁酯为前驱体(钛酸丁酯、水、无水乙醇的摩尔比为1∶20∶100,pH值为1.5),采用溶剂热合成法制备锐钛矿型TiO2溶胶和粉体。通过对不同反应温度下的产物进行分析,研究TiO2的结晶过程。结果表明:在反应初期,溶胶中存在Ti-O网络的类锐钛矿结构排列;随反应的进行,类锐钛矿结构的有序排列消失,Ti-O网络结构趋于无序化;进一步反应,无序的结构会发生重排,重新转变为类锐钛矿结构,同时析出晶核并长大形成锐钛矿型晶粒。

TiO2 sol and powder were prepared by solvothermal synthesis, using Ti（OC4H9）4 as a precursor （where mole ratio of Ti（OC4H9）4：H2O：C2H5OH=1：20：100, and pH=1.5）. The crystallization processes of TiO2 have been studied by analyzing the products obtained at different reaction temperatures. The results show that there is a Ti-O network with quasi anatase structure in the initial stage of the reaction. In the process of the reaction, the ordered arrangement of the structure disappears, and the Ti-O network structure tends to disordering. With further reaction, the disordered structure rearranges and turns to the quasi anatase structure again, while at the same time, the crystal nucleus is precipitated and grows gradually into anatase grain.