Spectroscopic properties of sol-gel derived nanoscaled hybrid materials

An organometallic sol-gel route is presented for the synthesis of concentrated 12-16- and 6-16-semiconductor cluster assemblies embedded in patternable organosilicate-copolymer films and monoliths. Bifunctional spacers such as aminosilanes, isoeugenol or phosphines have been employed successfully to both control the CdSe and WSe3 nucleation processes and protect the formed clusters from attack by silanol groups of the matrix lacquer. The size-dependent spectral response of the clusters may be tuned by careful choice of processing parameters. For example, in combined amino-silane/phosphine cluster sols, reversible spectral changes in the UV/Vis spectra are observed due to a ligand exchange induced growth and decomposition of the cluster aggregates. Alternatively, thermal treatment of the CdSe-organosilicate films allows control of the optical absorption onset without matrix damage. Furthermore, we wish to report the development of a new class of functional optical materials such as NIR-fluorescing Er3+/ZnO/organosilicate-hybrids.