Hierarchically mesoporous silica materials prepared from the uniaxially stretched polypropylene membrane and surfactant templates

Hierarchically mesoporous silica materials with a bimodal distribution were template-prepared from uniaxially stretched polypropylene membrane in the presence of a surfactant via a sol?gel process. Their regularity and morphologies were characterized by transmission electron microscopy (TEM), x-ray diffraction and Brunauer?Emmett?Teller?(BET) surface area analysis. The larger channel pores formed by removing the microfibrils of uniaxially stretched polypropylene membrane have a broad pore size distribution, and their size is around 13?nm. In contrast, the smaller mesopores formed by surfactant templates have a narrow distribution; their size is about 3.9?nm. The size of the smaller pores could be tuned from 2 to 6?nm by selecting different surfactants and by changing the concentration of reactants.