A novel approach for the synthesis of monodispersed porous silica microspheres with high surface area

Monodispersed porous silica microspheres are synthesized by the hydrolysis and condensation of tetraethoxysilane (TEOS) in a water-ethanol mixed solution containing 1-alkylamine as a template and hydrolysis catalyst. The as-prepared products were characterized with scanning electron microscopy (SEM), transmission electron microscopy (TEM), small angle X-ray diffraction (SAXRD), Fourier transform infrared spectroscopy (FTIR) and nitrogen adsorption, respectively. It was found that the alkyl chain length of 1-alkylamine and calcination temperature have an obvious influence on the particle size, morphology, specific surface area and pore structure of the as-prepared silica powder. The specific surface area, porosity and pore volume increased with increasing calcination temperature. Further observation showed that at 600 °C, with increasing the alkyl chain length of template from C₁₂ to C₁₈, the specific surface area decreased and the pore size, porosity and pore volume increased. This research may provide new insight into the control of morphology and pore structures of oxide materials.