Effect of alkali/mixed alkali metal ions on the thermal and spectral characteristics of Dy3+:B2O3-PbO-Al2O3-ZnO glasses

• Published in: Journal of non-crystalline solids 2018-02, Vol.481, p.191-201
• Main Authors: Lakshminarayana, G., Baki, S.O., Lira, A., Caldiño, U., Meza-Rocha, A.N., Kityk, I.V., Abas, A.F., Alresheedi, M.T., Mahdi, M.A.
• Format: Article
• Language: English
• Subjects: Decay lifetime; Dy3 +: B2O3-PbO-Al2O3-ZnO glass; Inokuti-Hirayama (I–H) model; Judd-Ofelt theory; Luminescence property; TGA/DSC
• ISSN: 0022-3093; 1873-4812
• DOI: 10.1016/j.jnoncrysol.2017.10.047

Thermal and spectroscopic features of 50 B2O3–10 PbO–10 Al2O3–10 ZnO–(x) Li2O–(y) Na2O–(z) K2O–1.0 Dy2O3 (mol %) (x=19, y=0, and z=0; x=0, y=19, and z=0; x=0, y=0, and z=19; x=9.5, y=9.5, and z=0; x=9.5, y=0, and z=9.5; x=0, y=9.5, and z=9.5) glasses, that were fabricated by utilizing melt-quenching approach, are investigated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), optical absorption, photoluminescence excitation (PLE), photoluminescence (PL), and PL decay lifetimes. PL spectra for all the Dy3+-doped samples show emission bands at 453nm (blue), 482nm (blue), 573nm (yellow), 662nm (red), and 752nm (red) corresponding to the 4I15/2→6H15/2, 4F9/2→6H15/2, 4F9/2→6H13/2, 4F9/2→6H11/2, and 4F9/2→6H9/2 transitions, respectively, upon excitation at 350nm. Here, Dy3+: Li–Na glass shows the highest PL intensity for all identified emissions. The yellow-to-blue (Y/B) emission intensity ratio (varied within the range 1.257–1.376), CIE chromaticity coordinates (x,y) (slight variation between (0.3410, 0.3802) and (0.3495, 0.3872), and correlated color temperatures (CCTs) (changed from 4953K to 5212K) are calculated following the PL spectra. Dy3+: 4F9/2 decay curves show non-exponential behavior and are fitted by the Inokuti-Hirayama (I–H) model, where S=6 shows best fit, indicating dipole-dipole (d-d) interactions for Dy3+ excited (donor) and ground state (acceptor) ions. •Alkali/mixed alkali based Dy3+: B2O3–PbO–Al2O3–ZnO glasses are evaluated for W-LEDs.•ΔT=Tx–Tg varied at 140–173°C, and 132–160°C for single, and mixed alkali glasses.•Dy3+: Li–Na glass shows the highest emission bands intensity among all the glasses.•The Y/B intensity ratio varied within the range 1.257–1.376 for the studied glasses.•All Dy3+-doped glasses CIE (x, y), and CCT values represent neutral white light region.