کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
7840576 | 1505869 | 2018 | 9 صفحه PDF | دانلود رایگان |
عنوان انگلیسی مقاله ISI
Transparent oxyfluoride glass-ceramics with NaGdF4 nanocrystals doped with Pr3+ and Pr3+-Yb3+
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کلمات کلیدی
موضوعات مرتبط
مهندسی و علوم پایه
شیمی
شیمی تئوریک و عملی
پیش نمایش صفحه اول مقاله
چکیده انگلیسی
Transparent oxyfluoride nano-glass-ceramics (GCs) containing NaGdF4 nanocrystals doped with 0.1Pr3+and 0.5Pr3+, and co-doped with 0.5Pr3+-2Yb3+ ions (mol%) were obtained by melting-quenching followed by heat treatments at temperatures near Tg. The addition of rare-earths (RE) ions affects the crystallization kinetics due to the progressive increase of Tg as RE concentration increases. X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM) show the precipitation of NaGdF4 nanocrystals with sizes between 9 and 30Â nm. The crystal size increases with the increasing amount of dopant. Energy dispersive X-ray (EDX) analysis confirms the incorporation of the RE ions in the fluoride nanocrystals in the glass-ceramics. This incorporation is also supported by optical characterization. Photoluminescence measurements shows a better resolved structure together with a narrowing of the Pr3+ emission and excitation spectra in the glass-ceramics compared to the precursor glass. The emission spectra and fluorescence decay curves from the 3P0 level of Pr3+ in the codoped samples support the existence of a Pr3+ â Yb3+ energy transfer with slight enhancement of the energy transfer efficiency in the GC sample.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Journal of Luminescence - Volume 193, January 2018, Pages 61-69
Journal: Journal of Luminescence - Volume 193, January 2018, Pages 61-69
نویسندگان
J.J. Velázquez, R. Balda, J. Fernández, G. Gorni, L. Pascual, G. Chen, M. Sundararajan, A. Durán, M.J. Pascual,