Highly efficient synthesis of ordered mesoporous silica materials with controllable microporosity using surfactant mixtures as templates

Ordered mesoporous silica materials (SBA-family) with 2-D hexagonal (p6mm) and 3-D cubic (Im3m) symmetry have been efficiently synthesized by using the mixture of triblock copolymer surfactant and sodium dodecylsulfonate as co-templates at relatively low concentration. X-ray diffraction (XRD), transmission electron microscopy (TEM), and nitrogen adsorption/desorption isotherms are used to characterize these mesoporous silica materials, and the results show that the mesoporous silica mateials synthesized from the mixed surfactants have better mesostructural order and smaller mesopore size, compared with mesoporous silica materials of SBA-15 and SBA-16. Moreover, the microporosity in these ordered mesoporous materials is well controlled by the weight ratios of polymer surfactant to anionic surfactant. Particularly, when P123 concentration in the starting gel is reduced to less than 0.4 wt.%, the walls of ordered hexagonal mesoporous silica are micropore-free.