Structural and morphological studies were carried out on cerium- and gadolinium-doped sol-gel silica glasses intended for scintillator applications, to deepen the understanding of rare earth ion incorporation into the glass matrix. Several compositions, ranging from 0 to 5 mol % Ce and from 0 to 8 mol % Gd, were studied by Raman spectroscopy. The vibrational response was compared to that of pure silica glasses: for cerium doping higher than 0.5 mol %, the F-2g Raman mode, characteristic of CeO2, was observed. The presence Of CeO2 nanocrystalline clusters, whose size depends on cerium concentration and thermal treatment, was confirmed also by X-ray powder diffraction (XRD) patterns and transmission electron microscopy (TEM) analyses. On the contrary, gadolinium-doped sol-gel silica glasses exhibited Raman spectra similar to those of pure silica glasses, at least for the investigated concentrations up to 8 mol %, and no crystalline particles were detected within the amorphous matrix.
DI MARTINO, D., Vedda, A., Angella, G., Catti, M., Cazzini, E., Chiodini, N., et al. (2004). Evidences of rare earth ion aggregates in a sol-gel silica matrix: The case of cerium and gadolinium. CHEMISTRY OF MATERIALS, 16(17), 3352-3356 [10.1021/cm049276m].
Evidences of rare earth ion aggregates in a sol-gel silica matrix: The case of cerium and gadolinium
DI MARTINO, DANIELA;VEDDA, ANNA GRAZIELLA;CATTI, MICHELE;CHIODINI, NORBERTO;MORAZZONI, FRANCA;SCOTTI, ROBERTO;SPINOLO, GIORGIO MARIO
2004
Abstract
Structural and morphological studies were carried out on cerium- and gadolinium-doped sol-gel silica glasses intended for scintillator applications, to deepen the understanding of rare earth ion incorporation into the glass matrix. Several compositions, ranging from 0 to 5 mol % Ce and from 0 to 8 mol % Gd, were studied by Raman spectroscopy. The vibrational response was compared to that of pure silica glasses: for cerium doping higher than 0.5 mol %, the F-2g Raman mode, characteristic of CeO2, was observed. The presence Of CeO2 nanocrystalline clusters, whose size depends on cerium concentration and thermal treatment, was confirmed also by X-ray powder diffraction (XRD) patterns and transmission electron microscopy (TEM) analyses. On the contrary, gadolinium-doped sol-gel silica glasses exhibited Raman spectra similar to those of pure silica glasses, at least for the investigated concentrations up to 8 mol %, and no crystalline particles were detected within the amorphous matrix.
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