TiO2-SiO2复合气凝胶：常压干燥制备及性能表征

Using cheap titanium tetrachioride and industrial watergiass as raw materials, TiO2-SiO2 composite aerogels were prepared via an ambient pressure drying process, by using Trimethylchlorosilane/Ethanol/Hexane solution to modify the sol-gel-derived TiO2-SiO2 wet gel. The morphology and properties of the aerogels were characterized by SEM, TEM, FTIR, XRD and N2 adsorption-desorption measurement. The results indicate that the obtained TiO2-SiO2 composite aerogels exhibit a porous structure, with a specific surface area of 1 076 m^2•g^(-1) and pore volume of 4.96 cm^3•g^(-1) after dried at 150 ℃. Moreover, the composite aerogels still show high porosity after calcined at 550 ℃, with a specific surface area of 856 m^2•g^(-1) and pore volume of 3.46 cm^3•g^(-1). The results of adsorption and photocatalytic degradation of rhodamine B show that TiO2-SiO2 composite aerogels have both good adsorption and photocatalytic properties. The synergistic adsorption/photocatalysis actixity of TiOrSiO2 composite aerogels was better than pure SiO2 aerogels and pure anatase TiO2 powder. Additionally, the adsorption/photocatalytic degradation rate is still up to 89% after being used for four times.