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Sol–Gel Synthesis of Solids

  1. Thibaud Coradin,
  2. Jacques Livage

Published Online: 15 MAR 2006

DOI: 10.1002/0470862106.ia223

Encyclopedia of Inorganic Chemistry

Encyclopedia of Inorganic Chemistry

How to Cite

Coradin, T. and Livage, J. 2006. Sol–Gel Synthesis of Solids. Encyclopedia of Inorganic Chemistry. .

Author Information

  1. Université Pierre et Marie Curie, Chimie de la Matière Condensée (CNRS) and Collège de France, Paris, France

Publication History

  1. Published Online: 15 MAR 2006

Abstract

The synthesis of glasses and ceramics via the sol–gel route is based on the inorganic polymerization of molecular precursors such as metal alkoxides. Precursor structure and reactivity can be chemically controlled via complexation or acid–base catalysis. Sol-gel chemistry allows the powderless processing of glasses and ceramics, at much lower temperatures than usual solid-state reactions. It provides a convenient and flexible access to nanoparticles, films, and fibres. Moreover, precursors are mixed at the molecular level and multicomponent materials can be formed. Thus, hybrid organic–inorganic materials have been made via the sol–gel route. The organic component can be used as a network modifier during the sol–gel synthesis and then withdrawn, allowing the formation of structured porous materials. It can also remain entrapped in the mineral matrix via weak interactions. Alternatively, organoalkoxysilanes allow covalent binding of organic moieties to silica networks. Such composites fill the gap between polymers and glasses and open new fields in materials science such as ‘sol–gel optics’ or bioencapsulation in mineral hosts.

Keywords:

  • sol-gel;
  • oxides;
  • silica;
  • metal alkoxides;
  • organic-inorganic hybrids;
  • functional materials