Physical, thermal, structural and optical properties of Dy 3+ doped lithium alumino-borate glasses for bright W-LED
| Autor: | R.S. Gedam, S. Gautam, S.R. Munishwar, P.P. Pawar |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
Materials science
Biophysics Analytical chemistry chemistry.chemical_element 02 engineering and technology 01 natural sciences Biochemistry Spectral line Optics 0103 physical sciences Photoluminescence excitation Emission spectrum Chromaticity 010302 applied physics business.industry Doping General Chemistry 021001 nanoscience & nanotechnology Condensed Matter Physics Atomic and Molecular Physics and Optics Amorphous solid chemistry Direct and indirect band gaps Lithium 0210 nano-technology business |
| Zdroj: | Journal of Luminescence. 183:79-88 |
| ISSN: | 0022-2313 |
| DOI: | 10.1016/j.jlumin.2016.11.027 |
| Popis: | Rare earth (RE) doped glasses have potential applications due to their emission efficiencies of 4f–4 f and 4f–5d electronic transitions. Among all the rare earths, Dy 3+ doped glasses have drawn much interest among the researchers for their intense emission in the visible region from 470 to 500 nm and around 570 to 600 nm. The physical, thermal, structural and optical properties of Dy 3+ doped lithium alumino-borate glasses (LABD glasses) have been studied for white LED (W-LED) application. The glasses were synthesized by conventional melt quench technique. X-ray diffraction spectra revealed the amorphous nature of the glass sample. An FTIR spectrum was carried out to study the glass structure and various functional groups present in the LABD glasses. Optical absorption spectra were recorded by UV–vis-NIR spectrometer. Allowed direct and indirect band gaps were obtained by Tauc's plot. Thermal parameters like glass thermal stability (∆T), Hruby's parameter (K gl ), etc. were calculated by DTA graph. Photoluminescence excitation and emission spectra's were measured at room temperature. The emission spectra shows two intense emission bands at around 482 nm (blue) and 574 nm (yellow) corresponds to the 4 F 9/2 → 6 H 15/2 and 4 F 9/2 → 6 H 13/2 transitions respectively along with one feeble band at 662 nm (red) corresponds to 4 F 9/2 → 6 H 11/2 transition. The CIE chromaticity co-ordinates were calculated for all glass samples. CIE chromaticity diagram shows glass LABD-4 containing 0.5 mol% Dy 2 O 3 with colour co-ordinates X = 0.34 and Y = 0.38 have highest emission intensity. These glasses having emission in the white region and thus can be used for bright white LED. |
| Databáze: | OpenAIRE |
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