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分别通过 Ti O2 和 Si O2 的单独溶胶和 Ti O2 / Si O2 复合凝胶 ,并添加干燥控制化学添加剂甲酰胺 ,形成比较完善的凝胶网络结构 ,同时通过正硅酸乙酯的乙醇溶液浸泡 ,低表面张力溶剂替换和分级陈化以及干燥等步骤 ,实现了块状 Ti O2 / Si O2 复合气凝胶的非超临界干燥制备 .所得 Ti O2 / Si O2 气凝胶为无色或乳白色轻质块状多孔固体 ,表观密度约 0 .4~ 0 .9g/ cm3,孔隙率约 80 %~ 95 % .它由直径约 1 0 nm的 Ti O2 和 Si O2微粒相互分散复合而成 ,孔洞直径约几十纳米 .其相态 Si O2 为无定形 ,Ti O2 为锐钛矿晶型 .随着焙烧温度的升高 ,直到 80 0℃不发生相变化
Respectively, by Ti O2 and Si O2 sol and Ti O2 / Si O2 alone gel, and add the drying control of chemical additives formamide, to form a relatively perfect network structure of the gel, while ethyl tetraethyl orthosilicate ethanol solution soak, Low surface tension solvent replacement and grading aging and drying steps to achieve a non-supercritical dry bulk Ti O2 / Si O2 composite airgel prepared Ti O2 / Si O2 airgel colorless or milky white light Bulk porous solid with an apparent density of about 0.4 ~ 0.9g / cm3 and a porosity of about 80% ~ 95%. It is composed of Ti O2 and Si O2 particles with a diameter of about 10 nm dispersed and combined with each other, About tens of nanometers, the phase Si O2 is amorphous, Ti O2 anatase crystal form with the calcination temperature, up to 80 0 ℃ phase change does not occur