Synthesis and characterization of mesoporous SiO2 by the chemical precipitation method

Abstract

Mesoporous silicon dioxide (SiO2) powders with different specific surface areas were prepared by the chemical precipitation method from sodium metasilicate, hydrochloric acid, and cetyl trimethylammonium bromide (CTAB). The obtained samples were characterized by the BET method — differential scanning calorimetry/thermogravimetry (DSC/TG), X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and transmission electron microscopy (TEM). The effects of some factors, such as pH, concentration of sodium metasilicate, concentration of hydrochloric acid solution, and reaction temperature, on the specific surface area were investigated. Mesoporous SiO2 with a BET-specific surface area of 1041.382/g and an average pore size of 5.78nm was made under the following conditions: pH, 8; concentration of sodium metasilicate, 0.4mol/L; concentration of hydrochloric acid, 1.0mol/L; reaction temperature, 30°C.