Publication Date:
2012-12-13
Description:
The influence of the addition of 1 mol% Tm 2 O 3 on the nanocrystallization of LaF 3 in a glass of composition 55 SiO 2 –20 Al 2 O 3 –15 Na 2 O –10 LaF 3 (mol%) has been studied. Tm 2 O 3 affects the phase separation in the glass and delays the onset of crystallization with respect to the undoped glass. Additionally, the maximum LaF 3 crystal size is slightly greater than that in the undoped glass–ceramics. The microstructural and compositional changes in the glass matrix have been studied using several techniques, including viscosity, dilatometry, X-ray and neutron diffraction (XRD, ND), quantitative Rietveld refinement, transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and Raman spectroscopy. Photoluminescence measurements indicate that the Tm 3+ ions are distributed between the glassy matrix and LaF 3 crystals. Eu 2 O 3 has been used as structure probe and part of the Eu 3+ ions are reduced to Eu 2+ when incorporated in the LaF 3 nano-crystals. Up-conversion spectra under IR-excitation show a higher intensity of the blue emission in the Tm -doped glass–ceramic compared with that in the glass.
Print ISSN:
0002-7820
Electronic ISSN:
1551-2916
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
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