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

• Published in: Langmuir Vol. 28; no. 33; pp. 12334 - 12340
• Main Authors: Esquena, Jordi, Nestor, Jérémie, Vílchez, Alejandro, Aramaki, Kenji, Solans, Conxita
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 21.08.2012
• Subjects: Alkanes - chemistry; Chemistry; Colloidal state and disperse state; Emulsions; Emulsions. Microemulsions. Foams; Exact sciences and technology; General and physical chemistry; Polyethylenes - chemistry; Polypropylenes - chemistry; Porosity; Porous materials; Scattering, Small Angle; Silanes - chemistry; Silicon Dioxide - chemistry; Surface physical chemistry; Surface-Active Agents - chemistry; Water - chemistry; X-Ray Diffraction; Crystalline phase; Binary compound; Cubic crystals; Non ionic surfactant; Liquid phase; Nitrogen; Small angle X ray scattering; Continuous phase; Porous material; Liquid crystals; Silica; Mesoporosity; Template; Sorption; Pore size; Emulsion; Transmission electron microscopy; Adsorption; Preparation; Distribution; Surface area; Block copolymer; Macroporosity
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la302120f

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 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 m2/g.