ABSTRACT
This chapter examines the physics and chemistry of sol–gel processing and the ways in which these relate to the practical fabrication of ceramics and glasses. The sol–gel is used to describes the preparation of ceramic materials by a process that involves the preparation of a sol, the gelation of the sol, and the removal of the liquid. Applications sol–gel processing can provide substantial benefits, such as the various special shapes that can be obtained directly from the gel state, control of the chemical composition and microstructure, and low processing temperatures. While polymeric gels are the subject of considerable research and publication, the particulate systems include some of the most successful industrial applications of sol–gel technology. Metal alkoxides are the most common precursors used in sol–gel processing because they react readily with water. The most commonly used precursors for the sol–gel processing of silica are tetraethoxysilane.
