Preparation of mesoporous/macroporous materials in highly concentrated emulsions based on cubic phases by a single-step method.

Jordi Esquena, Jérémie Nestor, Alejandro Vílchez, Kenji Aramaki, Conxita Solans

Index: Langmuir 28(33) , 12334-40, (2012)

Full Text: HTML

Abstract

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 C(12)(EO)(8) and a PEO-PPO-PEO block copolymer nonionic surfactant, with a cubic liquid crystalline phase of the Fd3m 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 m(2)/g.