New Transparent Chalcogenide Materials Using a Sol−Gel Process

We report a scheme for the II−VI chalcogenide sol−gel synthesis, using cadmium sulfide as a model system. Highly concentrated sols are obtained by surface complexation of CdS nanocrystals with 4-fluorophenylthiol. Controlled aggregation and gelation is then achieved by a progressive decomplexation of the particles via a thiol oxidation reaction. The gels may finally be processed as solid monoliths or thin films and dried to obtain transparent nanostructured materials.