P. Rehana; O. Ravi; B. Ramesh; G.R. Dillip; C. Madhukar Reddy; S. W. Joo; B. Deva Prasad Raju
Abstract
A facile melt quenching technique was employed to prepare Eu 3+ -ions doped TRZNB glasses using commercial powders through mixing the specific weights of batches. The compositions prepared were 10TeO2 + 15RO + 5ZnO + 10Nb2O5 + 59B2O3 + Eu2O3 (where R= Mg, Ca and Sr). Under 395 nm excitation wavelength, ...
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A facile melt quenching technique was employed to prepare Eu 3+ -ions doped TRZNB glasses using commercial powders through mixing the specific weights of batches. The compositions prepared were 10TeO2 + 15RO + 5ZnO + 10Nb2O5 + 59B2O3 + Eu2O3 (where R= Mg, Ca and Sr). Under 395 nm excitation wavelength, p < /span>hotoluminescence (PL) and lifetime measurements of Eu 3+ -doped TRZNB glasses were recorded and reported. The PL spectra composed of five emission bands that are originating from the 5 D0 metastable state to 7 FJ (J = 0 - 4) lower lying states. Using the emission intensities of 5 D0→ 7 F2 and 5 D0→ 7 F4 transitions, respectively, the Judd–Ofelt (J–O) intensity parameters such as Ω2 and Ω4 were calculated by considering the magnetic dipole (MD) 5 D0→ 7 F1 transition as reference. The radiative parameters such as spontaneous emission probabilities (AR), lifetimes (τm), branching ratios (βm) for different excited states were estimated theoretically. For all the glasses, the decay profiles were fitted to the single exponential equation. The obtained intense red emission at about 616 nm assigned to the 5 D0 → 7 F2 transition suggested the potentiality of present Eu 3+ -doped TRZNB glasses as a laser host.
Atul N. Yerpude; Sanjay Janrao Dhoble; B. Ramesh; Borelli Deva Prasad Raju
Abstract
In this study, Sm 3+ - and Dy 3 -doped SrAl4O7 phosphors were synthesized by combustion method. X-ray diffraction (XRD) measurement confirmed the monoclinic crystal structure of SrAl4O7. Sr-O and Al-O bonds were identified by Fourier transform infrared (FTIR) spectroscopy. Under 352 nm excitation, the ...
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In this study, Sm 3+ - and Dy 3 -doped SrAl4O7 phosphors were synthesized by combustion method. X-ray diffraction (XRD) measurement confirmed the monoclinic crystal structure of SrAl4O7. Sr-O and Al-O bonds were identified by Fourier transform infrared (FTIR) spectroscopy. Under 352 nm excitation, the SrAl4O7: Dy 3+ phosphor shown emission bands at 475 nm (blue) and 574 nm (yellow) that are due to 4 F9/2→ 6 H15/2, 6 H13/2 transitions, respectively. Photoluminescence spectra (PL) of SrAl4O7: Sm 3+ phosphor has shown bright orange red emission at 598 nm with an excitation wavelength of 405 nm. The decay curve of Sm 3+ and Dy 3+ single doped SrAl4O7 phosphors were well fitted to a bi-exponential function. The obtained results show that the prepared phosphors may be applicable in the field of eco-friendly solid state lighting technology.
