Hierarchical Meso-Mesoporous and Macro-Mesoporous Silica Templated by Mixtures of Polyoxyethylene Fluoroalkyl Ether and Triblock Copolymer
Abstract
We report here the synthesis of different kinds of hierarchical porous silica materials by using mixtures of an amphiphilic block copolymer (Pluronic P123) and a nonionic fluorinated surfactant. In particular, we have taken advantage of the difference in polarities between the two compounds to design dual-mesoporous materials through the cooperative templating mechanism (CTM). We have undertaken a complete study of this system by varying the composition of the mixed micelles and the synthesis conditions. We have shown that both the dual-mesoporosity and the mesopore ordering are favored when materials are prepared with fluorine-rich and P123-rich micelles. However, when the P123-rich micelles predominate, the mesostructure is less organized and the dual-porosity depends on the P123 content. In addition, concentrated emulsions were formed by incorporating perfluorodecalin (PFD) in the surfactant mixture, and hierarchical macro-mesoporous materials were prepared by combining the CTM and the emulsion templating mechanism.