Preparation of Mesoporous/Macroporous Materials in Highly Concentrated Emulsions Based on Cubic Phases by a Single-Step Method

A novel and simple single-step method for the preparation of meso/macroporous silica materials is described, which consists in templating in highly concentrated emulsions with a cubic liquid crystal in the continuous phase. Tetraethyl orthosilicate (TEOS) was solubilized in the aqueous continuous phase of highly concentrated emulsions stabilized by C₁₂(EO)₈ and a PEO–PPO–PEO block copolymer nonionic surfactant, with a cubic liquid crystalline phase of the <i>Fd</i>3<i>m</i> type. The resulting silica materials were characterized by small-angle X-ray scattering, nitrogen sorption and transmission electron microscopy. The results showed that a dual pore size distribution was obtained, consisting of mesopores in the nanometer range and macropores between 1 and 5 μm. These dual meso/macroporous silicas with bimodal pore size distribution can possess specific surface areas higher than 400 m²/g