Spectroscopic, thermal and structural properties of rare earth (RE) doped zinc borotellurite glasses and nano-glass-ceramics are characterized using UV–Vis-NIR spectroscopy, photoluminescence (PL), decay time measurements, differential thermal analysis (DTA), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Raman spectroscopy. It is found that there is an increase in thermal stability factor with the increase of dysprosium ion (Dy3+) concentration. XRD results confirm the amorphous character of glasses and the presence of α-TeO2 and γ-TeO2 phases in nano-glass-ceramics. Raman spectroscopy results show the formation of non-bridging oxygens (NBO's) by the addition of Dy2O3 at the expense of Te-O-Te linkages of TeO4 units and there is formation of the crystalline phases in the prepared glasses on heat treatment. A considerable change in the values of Judd-Ofelt parameters of glasses is observed after the heat treatment. The CIE Coordinates of TBZDy0.5GC (0.32, 0.34) are closer to that for commercial pc-LED (0.32, 0.33). There is a decrease in the lifetime is observed with the increase in concentration of Dy3+ due to concentration quenching. The high stimulated emission cross-section (σemi), lifetime and quantum efficiency (η) values for prepared glasses and nano-glass-ceramics imply their suitability for the fabrication of white light laser.
- Borotellurite nano-glass-ceramics
- Decay curves analysis
- Judd-Ofelt analysis
- Radiative properties