Synthesis of monodispersed silica nanoparticles with high concentration by the Stober process

Silica nanoparticles with high concentration were prepared by the sol-gel process based on the Stober method using tetraethoxysilane as a starting material. It was found that silica sol with about 4 wt% in concentration and with a diameter of about 10 nm was obtained by controlling the reaction conditions in the Stober process. By removing the solvent under a reduced pressure, the particle concentration was increased up to 15 wt% without aggregation.