Aero-sol-gel synthesis of nanostructured silica powders

Nanostructured silica powders are synthesized by a nonpyrolytic, room-temperature aerosol-gel process. Hydrolysis and condensation of tetraethoxysilane (TEOS) and tetramethoxysilane (TMOS) precursors produce nanosized silica powders that have specific surface areas greater than 400 m(2)/g. This paper reports on a novel synthetic approach and characterization of the morphology, particle growth process, surface area, and chemical composition using small-angle X-ray scattering (SAXS), N-2 adsorption, and elemental analysis. Structural models for the morphology and growth process of the silica particles are suggested. The effects of reactant-temperature and powder sintering on the specific surface area of silica are discussed.