J. Phys. IV France 02 (1992) C2-141-C2-144
Nucleation and crystallisation in xerogel induced and probed by CrW. NIE1 and G. BOULON2
1 LSM/CRT, Kodak-Pathé, 71102 Chalon sur Saône, France
2 Laboratoire de Physico-Chimie des Matériaux Luminescents, Université Lyon I, URA au CNRS n° 442, Bâtiment 205, 69622 Villeurbanne Cedex, France
Nucleation and crystallization from xerogels of the system SiO2-ZnO-Al2O3 are induced and probed by Cr. Besides the traditional techniques, such as X-ray diffraction, SAXS and TEM, ESR and optical techniques especially laser spectroscopy are employed for the investigation of the structural evolution during thermal treatments of these xerogels. Cr is served not only as a structure probe but also a nucleating agent. The devitrification of the system is found to be essentially initiated by the presence of traces of chromium.
© EDP Sciences 1992