摘要
以钛酸四丁酯(TBT)、正硅酸乙酯(TEOS)为原料,制备出TiO_2和SiO_2溶胶,研究了不同水解抑制剂以及水解抑制剂的用量对TiO_2溶胶的影响。最终确定以HCl为水解抑制剂制备出稳定的TiO_2溶胶;两种溶胶混合后,研究了pH值对复合凝胶透明度的影响。结果表明,当pH值为5.5时,凝胶时间适当且复合湿凝胶透明度较好;随着TiO_2含量的增加,比表面积减小、锐钛矿衍射峰强度增强;从TEM图可以看出,锐钛矿型TiO_2晶体均匀分散在SiO_2气凝胶网络结构中。
Sols of TiO2 and SiO2 are prepared using TBT and TEOS as the raw material, separately. The effect of category and dosage of different hydrolysis restrainers on the sol of TiO2 is investigated. Ultimately, the stable sol of TiO2 is prepared taking HCl as hydrolysis restrainer. After the two kinds of sols are mixed, the effect of pH value on SiO2-TiO2 composite sol is investigated. The result shows that, when the pH value is 5.5, the gelation time is proper and the transmittance of SiO2-TiO2 composite alcogels is better. With increase of the content of TiO2, the specific sur- face area of SiO2-TiO2 composite aerogels decreases and the intensity of X-ray diffraction peak of anatase TiO2 strengthens. The TEM image shows that the anatase TiO2 crystal disperses uniformly in the network of SiO2 aerogel.
基金
江苏省自然科学基金项目(BK2007586)
江苏省博士后科研资助计划项目(0701012B)
