Preparation of SiO 2 Aerogel Derived from TEOS Catalyzed by HF

Nano porous material SiO 2 aerogels were prepared from TEOS / C 2H 5OH and catalyzed by HF The effects of some variable parameters such as catalyst ,pH,water and solvent on the sol gel process were studied The results showed that catalyst HF greatly influences the velocity of the hydrolysis and condensation of the TEOS The special effect of the HF catalyst on the sol gel process was also discussed BET and TEM showed that the silica aerogels have a high inner surface area (673 8m 2g -1 )and the diameter of the skeletal particles is about 5 10 nm while the pore size is about 5～30 nm