Preparation of monodisperse nanosized mesoporous silica

Using the cationic surfactant-cetyltrimethylammonium bromide(CTAB)as template, tetraethyl orthosilicate(TEOS)as silica source and nonionic sufactant-triblock copolymer F127 as dispersant,the monodisperse nanosized mesoporous siliceous MCM-41 was prepared by room temper- atural synthesis method in basic media.The samples were characterized by techniques such as XRD, TEM.HRTEM,SEM,IR and N_2 physisorption.In addition, the influences of different molar ratios of F127 to CTAB on mesoporous crystalline structure,surface structure,pore size distribution and the dispersity of nanosized mesoporous siliceous MCM-41 were also systemically studied.The results show that a suitable amount of F127 can greatly improve the ordered structure of pore array, while an excessive amount of F127 will destroy the ordered structure.When the molar ratio of F127 to CTAB was ranged from 0.04 to 0.08,the synthesized samples were nanoparticle, monodispersed,single-pore distributed, huge pore volume and highly ordered mesoporous structure.