Synthesis of SBA-16 and SBA-15 mesoporous silica crystals templated with neutral block copolymer surfactants Original Research Article

Using C8TMAB-SDS-F127 ternary surfactants as mesostructural template, SBA-16 mesoporous silica crystals in the rhombdodecahedronal shape can be conveniently obtained at pH≈2.0. It was found that the C8TMAB-SDS catanionic surfactants act as micellization promoter for the F127 surfactant but do not alter the SBA-16 mesostructure. The SBA-15 mesoporous silica crystals in a rod shape were also synthesized using P123 surfactant as a template. However, when the pH value of the silicate solution was adjusted to 5.0, fast silica condensation rate leads to the formation of irregular particles rather than crystals. The mesoporous silica crystals exhibit well-ordered mesostructure, high surface area and large pore size and volume. Therefore, the calcined mesoporous silica crystals were used as a solid template to prepare the mesoporous carbon crystals.