From amorphous phase separations to nanostructured materials in sol-gel derived ZrO2 : Eu3+/SiO2 and ZnO/SiO2 composites

摘要

ZrO2Eu3+-SiO2 and ZnO-SiO2 composites have been synthesized by a sol-gel method by using a specific gelation and drying procedure. In the two cases we were able to produce large and transparent monolithic samples. Microstructural properties of these materials were investigated by thermo-differential and thermo-gravimetric analysis, X-ray diffraction, transmission electron microscopy and small angle X-ray scattering. The existence of a miscibility gap in both systems results in the formation of nanocomposites where crystallized zirconia or amorphous zinc oxide nanoparticles are dispersed in a silica glass matrix. These two kinds of nanocomposites are potential high efficiency luminescent materials because the nanoparticles size is easily controlled by the annealing conditions. (c) 2006 Elsevier B.V. All rights reserved.