Highly Swollen Liquid Crystals as New Reactors for the Synthesis of Nanomaterials
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- 作者：Geetarani Surendran ; Miriam S. Tokumoto ; Eduardo Pena dos Santos ; Hynd Remita ; Laurence Ramos ; Patricia J. Kooyman ; Celso Valentim Santilli ; Claudie Bourgaux ; Philippe Dieudonné ; and Eric Prouz
- 刊名：Chemistry of Materials
- 出版年：2005
- 出版时间：March 22, 2005
- 年：2005
- 卷：17
- 期：6
- 页码：1505 - 1514
- 全文大小：1261K
- 年卷期：v.17,no.6(March 22, 2005)
- ISSN：1520-5002
文摘
Synthesis and self-assembly of nanomaterials can be controlled by the properties of soft matter. Onone hand, dedicated nanoreactors such as reverse microemulsions or miniemulsions can be designed. Onthe other hand, direct shape control can be provided by the topology of liquid crystals that confine thereacting medium within a specific geometry. In the first case, the preparation of micro- or miniemulsionsgenerally requires energetic mechanical stirring. The second approach uses thermodynamically stablesystems, but it remains usually limited to binary (water + surfactant) systems. We report the preparationof different families of materials in highly ordered quaternary mediums that exhibit a liquid crystal structurewith a high cell parameter. They were prepared with the proper ratios of salted water, nonpolar solvent,surfactant, and cosurfactants that form spontaneously swollen hexagonal phases. These swollen liquidcrystals can be prepared from all classes of surfactants (cationic, anionic, and nonionic). They contain aregular network of parallel cylinders, whose diameters can be swollen with a nonpolar solvent, that areregularly spaced in a continuous aqueous salt solution. We demonstrate in the present report that bothaqueous and organic phases can be used as nanoreactors for the preparation of materials. This propertyis illustrated by various examples such as the synthesis of platinum nanorods prepared in the aqueousphase or zirconia needles or the photo- or 
-ray-induced polymerization of polydiacetylene in the organicphase. In all cases, materials can be easily extracted and their final shapes are directed by the structure-directing effect imposed by the liquid crystal.
-ray-induced polymerization of polydiacetylene in the organicphase. In all cases, materials can be easily extracted and their final shapes are directed by the structure-directing effect imposed by the liquid crystal.