Study on Preparation of Nanometer Silicon Dioxide by Sol - gel Method
Huang Zhijie Fei Yiwei Shang Zhenfeng Huang Zhining (Xuzhou Air Force College , Xuzhou 221000)
Nanometer SiO2 was prepared by sol - gel method. The effects of test conditions on the preparation of nanometer SiO2 were examined. The surface structure of nanometer SiO2 was analyzed. The result showed that nanometer SiO2 with the diameter in the range of 20 - 40 nm was prepared using sodium silicate and ethyl acetate. BET specific area could reach 400 m2/g,sometimes up to 500 m2/g.The content of ethyl acetate and reaction temperature could have significant influence on the specific area and total pore volume of nanometer SiO2 while the heat treatment had little influence on the diameter of SiO2 , but the silicon - hydroxy of nanometer SiO2 would condense to lose water and form Si-O-Si bond, leading to the collapse of pore structure and decrease of the specific area.