Absorption and emission analysis of zinc borotellurite glass doped with dysprosium oxide nanoparticles for generation of white light

A series of zinc borotellurite glass doped with Dy₂O₃ nanoparticles with chemical formula ${\left\{{\left[{\left({\mathrm{TeO}}_2\right)}_{0.7}{\left(B_2{O}_3\right)}_{0.3}\right]}_{0.7}{\left(\mathrm{ZnO}\right)}_{0.3}\right\}}_{1-x}{\left({\mathrm{Dy}}_2{O}_3\mathrm{NP}\right)}_x$ (where x = 0.01, 0.02, 0.03, 0.04 and 0.05 M fraction) has been fabricated by using conventional melt-quenching method. In this work, absorption and emission analysis of the glass systems have been done. The absorption data are obtained from the UV–Vis spectroscopy while the emission spectrum of the glass systems is recorded by using the Luminescence spectrometer. From the absorption data, the direct and indirect optical band gaps for the glass systems are calculated. Both of the band gaps are found to decrease as opposed to the concentration of Dy₂O₃ nanoparticles. The decrement of the optical band gaps leads to the increment of the refractive index of the glass systems. From the emission spectra, two transition bands are observed, which represent the transition from ⁴F_9/2 to ⁶H_15/2 and ⁶H_13/2. Other than that, the x and y CIE chromaticity coordinates are determined from the emission spectra and are found in the region of white light. The values of the correlated colour temperature for this glass systems are in between 4104.22 and 4886.17 K and is in the neutral white light region.