Controlled preparation of rod- and top-like MCM-41 mesoporous silica through one-step route

Rod- and top-like mesoporous silica particles have been synthesized through one-step route. Synthetic conditions such as co-solvent, temperature, ionic strength, alkalinity, and reactant ratios that affect the mesostructures and macrostructures of mesoporous materials have been extensively studied. Rod and top with two head particles have been synthesized in mixed ethanol/water solutions. As the increase of the amount of ammonia, the aspect ratios of length/diameter of the particles decrease. At lower temperature highly ordered mesoporous silica with hexastyle structure can be obtained more easily under different alkalinity. As the increase of the temperature, mesoporous silica transforms to rod-like shape and the aspect ratios of length/diameter decrease. When the temperature is higher enough, spherical particles can be prepared and there are still defects existing in mesostructure.