Phase transformation in mesoporous silica films induced by the degradation of organic moiety

We demonstrate a phase transformation approach for selective control of mesophase in a silica film. Here, the phase transformation is induced by the degradation of organic moiety during calcination of the film. The films are prepared using Brij-30 [C-12 H-25 (OCH2CH2)(4)OH] as a structure directing agent and TEOS (tetraethylorthosilicate) as a source of silica under acidic conditions. The degree of silica condensation of the SiO2/Brij-30 mesophase is found to be a crucial factor enabling the phase transformation.