论文部分内容阅读
以正硅酸乙酯为硅源,用溶胶—凝胶法通过常压干燥制备SiO2气凝胶,在溶胶—凝胶的过程中加入扩孔剂,着重考察以乌洛托品作为扩孔剂的用量、水解时间、水解温度、焙烧温度等因素对SiO2气凝胶孔径的影响。采用红外波谱(FTIR)表征了样品具有SiO2气凝胶的骨架结构和特定的表面基团,电镜(SEM)说明了样品有很好的分散性,热重(TG)说明经过扩孔的SiO2气凝胶依然有良好的热稳定性、BET对SiO2气凝胶表征显示了样品有较大的比表面积(400～1 200m2/g)、孔径(10～21nm)、孔容(0.5～2.5cm3/g)。
SiO2 tetraethyl orthosilicate was used as the silicon source and SiO2 airgel was prepared by the sol-gel method at atmospheric pressure. The pore-expanding agent was added during the sol-gel process. The investigation focused on the use of urotropin as a pore-expanding agent Of the amount, hydrolysis time, hydrolysis temperature, calcination temperature and other factors on the pore size of SiO2 aerogels. The structure and specific surface groups of SiO2 aerogels were characterized by Fourier Transform Infrared Spectroscopy (FTIR). Electron microscopy (SEM) showed that the samples had good dispersibility. The thermogravimetry (TG) The gel still has good thermal stability. The BET specific surface area of SiO2 aerogels shows that the samples have larger specific surface area (400-1 200m2 / g), pore size (10-21nm), pore volume (0.5-2.5cm3 / g).