Fullerenes in sol-gel materials

The family of fullerene molecules is composed of a large variety of compoun ds that have been synthesized following the discovery of C-60 in 1985. The chemistry of fullerenes, developed in these last years, has allowed designi ng the properties of this family of molecules for specific applications in materials science. One of the main tasks to build up solid state devices ba sed on fullerenes is the synthesis of materials doped with a highly dispers ed and homogeneous distribution of fullerenes. Many of the peculiar photoph ysical properties, such as the reverse saturable absorption used to obtain a solid state optical limiter, are in fact lost in the aggregates of fuller enes. Sol-gel processing allows preparing inorganic oxides and hybrid organ ic-inorganic materials at low temperatures and presents an interesting alte rnative to organic polymers to entrap molecules of the fullerene family in a solid matrix. Porous inorganic solids and aerogels are also important cla sses of materials that can be synthesized via sol-gel and can act as hosts of fullerenes. In the present article we have reviewed the main achievement s of sol-gel processing of fullerene based nanocomposite materials.