کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5402822 1392742 2010 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Role of Al coordination in barium phosphate glasses on the emission features of Ho3+ ion in the visible and IR spectral ranges
کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه شیمی شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
Role of Al coordination in barium phosphate glasses on the emission features of Ho3+ ion in the visible and IR spectral ranges
چکیده انگلیسی
The glasses of the composition (39−x)BaO-xAl2O3-60P2O5:1.0Ho2O3 (in mol%) with x value ranging from 1.0 to 4.0 have been synthesized. The IR spectral studies of these glasses have indicated that there is a gradual transformation of Al3+ ions from tetrahedral to octahedral with increase in the concentration of Al2O3 up to 3.0 mol%. Optical absorption and fluorescence spectra (in the visible and NIR regions) of these glasses have been recorded at room temperature. The Judd-Ofelt theory could successfully be applied to characterize the absorption and luminescence spectra of Ho3+ ions in these glasses. From the luminescence spectra, various radiative properties like transition probability A, branching ratio βr, the radiative lifetime τr and emission cross-section σE for various emission levels of these glasses have been evaluated. The radiative lifetime of the 5S2→5I8 (green emission) transition has also been measured. The variations observed in these parameters have been discussed in the light of varying co-ordinations (tetrahedral and octahedral positions) of Al3+ ions in the glass network. The influence of hydroxyl groups on the luminescence efficiency of the transition 5S2→5I8 has also been discussed. Finally the optimum concentration of Al2O3 for getting maximum luminescence output has also been identified and reported.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 130, Issue 3, March 2010, Pages 498-506
نویسندگان
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