Adjustment of the morphology of MCM-41 silica in basic solution

Abstract MCM-41 silica particles with rich morphologies were prepared in a strong basic solution under a variety of conditions. It was found that the morphology of mesostructured silica was mainly affected by the rate difference between silica condensation and mesostructure formation. The effect of various parameters such as types and amounts of the cosolvents, degree of the dilution, amount of the surfactant, and pH value on the size of rate difference was studied systematically. Depending on the rate difference between silica condensation and mesostructure formation, mesoporous MCM-41 particles with various morphologies could be achieved, including spheres, hexagonal rods, spiral, orange, and gyroid.