Incorporation of Ce3+ in crystalline Gd-silicate nanoclusters formed in silica
2011; Elsevier BV; Volume: 132; Issue: 2 Linguagem: Inglês
10.1016/j.jlumin.2011.09.016
ISSN1872-7883
AutoresFederico Moretti, A. Vedda, N. Chiodini, Mauro Fasoli, A. Lauria, Vítězslav Jarý, Romana Kučerková, E. Mihóková, Angeloclaudio Nale, M. Nikl,
Tópico(s)Mineralogy and Gemology Studies
ResumoStructural and optical properties of sol–gel silica based glassceramics doped with 0.1 mol% Ce and codoped with Gd at high concentrations, from 5 mol% up to 40 mol%, are investigated and compared to those of analogous samples doped only with Ce. Raman scattering, transmission electron microscopy, and x-ray diffraction reveal the formation of Gd apatite-like silicate (Gd4.67O(SiO4)3) and of Gd pyrosilicate (Gd2Si2O7) nanophases whose morphology and crystallinity depend on the Gd concentration and thermal treatments. Optical absorption measurements demonstrate the role of the densification atmosphere in modifying the charge state of Ce ions. The incorporation of Ce3+ ions in the nanophases is put in evidence by photo- and radio-luminescence results.
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