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Abstract The present study reports preparation and characterization of Dy3+-doped PbO free alkali-heavy-metal-borate glasses for luminescent applications. The amorphous nature of the glasses and the presence of various structural groups like BiO 6 , BO 3 and BO 4 were confirmed through XRD and FTIR measurements. The Oscillator strength of Dy3+ absorption transitions as well as the bond formed with the O2− ion in the glass network were determined using the absorption spectra. Radiative parameters extracted from Judd-Ofelt theory proved the degree of suitability of prepared glasses for lasing applications. The photoluminescence spectra exhibited the emission characteristics of Dy3+ ions and used to calculate the branching ratio, stimulated emission cross-section and radiative lifetime. Metastable lifetimes of Dy3+ ions were obtained through exponential fitting of respective decay profiles. The luminescence quenching phenomena was reasoned using Inokuti-Hirayama (I H) model. The optical gain and quantum efficiency values clearly suggested Dy3+ doping at 0.3 mol% was optimum for 587 nm lasing action. Further, CIE chromaticity plot indicated the possible applications in solid state lighting devices. The thermoluminescence glow curves of 0.3 mol% Dy3+-doped glasses were considered for gamma irradiation and kinetic parameters of the same were evaluated using Computerized Glow Curve Deconvolution (CGCD) technique. Graphical abstract Image 10644633 [ABSTRACT FROM AUTHOR]

Abstract Present study reports the effects of varying concentrations of Pr3+ ions on the optical properties of 10ZnO-5Na 2 CO 3 -10Bi 2 O 3 -75-xB 2 O 3 -xPr 6 O 11 (x = 0.1–1 mol%) glasses prepared through melt-quench technique with an aim to achieve suitable optical gain medium for optoelectronic applications. Minimal changes in the measured density, X-Ray diffractogram and Fourier Transform Infrared spectra of the prepared samples confirmed the stability of the glass structure even after 1 mol% doping of the Pr3+. Bonding nature of Pr3+ ion with surrounding ligands and Judd-Oflet (J-O) intensity parameters of the glasses were determined using optical absorption spectra. The photoemission spectra exhibited reddish orange emission around 605 nm at 445 nm excitation. The calculated color chromaticity with x = 0.5847, y = 0.3701 coordinates for 0.1 mol% of the Pr3+ in the glasses suggests suitable optical gain medium for reddish orange LED applications. Metastable lifetimes of the Pr3+ ion were found-out by exponential fitting to the decay profiles. Lasing parameters of the glasses such as branching ratio, radiative transition probability and stimulated emission cross-section of 1D 2 →3H 4 transition were calculated using JO parameters indicating 0.1 mol% Pr3+-doped glasses suitable for 605 nm solid-state laser applications. The mechanism of energy transfer is determined by applying the Inokuti-Hirayama model and was found to involve a dipole-dipole type of interactions. Thermoluminescence (TL) glow curves of the gamma-ray treated 0.1 mol% Pr3+-doped zinc sodium bismuth borate glasses were de-convoluted using Computerized Glow Curve Deconvolution method to evaluate the energy storage properties of the glasses. The intensity variation of the TL component peak (CP2) at 500 K showed linear behavior up to 3 kG y suggesting application in high dose measurements. Graphical abstract Image 1 Highlights • Praseodymium doped zinc sodium bismuth borate glasses were prepared by melt quench technique. • The negative value of the bonding parameter revealed the ionic bonding between the Pr3+ ions with surrounding oxygen. • Hypersensitive transitions 3H 4 →3F 3 and 3H 4 →3P 2 of Pr3+ ions exhibited maximum values of oscillator strength values. • JO intensity parameters of 0.1 mol% Pr3+ doped glass showed very high rigidity and symmetry around Pr3+ ions. • CIE chromaticity diagram confirmed reddish orange color emission of these glasses under the 445 nm excitation. • Deconvoluted TL curve of fitted with 5 peaks and peak at 505 K showed linear dose response up-to 3 kGy gamma ray. [ABSTRACT FROM AUTHOR]