Summary: | Stable anatase is attractive to its notable functions for photo catalysis and photon-electron transfer. Stable anatase TiO2 containing amorphous SiO2 aerogel was prepared by hydrolysis of Ti (OC3H7)4 and Si (OC3H7)4 in a 2-propanol solution with acid catalyst. The solvent in wet gels was supercritically extracted in CO2 at 60 °C and 22 Mpa. Thermal evolutions of the microstructure of the gels were evaluated by TGADTA, N2 adsorption and XRD. A stable anatase TiO2 containing amorphous SiO2 aerogel with a BET specific surface area of 365 m2/g and a total pore volume of 0.20 cm3/g was obtained as prepared condition. The anatase phase was stable after calcination up to 1000°C, and BET specific surface area, total pore volume and average pore diameter did not change significantly after calcination up to 900 °C.
Keywords: Supercritical extraction, sol-gel, aerogel, stable anatase structure.
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