Thermal and optical properties of lithium-zinc-tellurite glasses

(100-X-Y)TeO2-XLi2O-YZnO, X = 10, 15 and 20, Y = 0, 5, 10, 15, 20, 25 and 30 mol%, glasses have been prepared by the melt quenching technique. Density and molar volume have been identified for every glass sample. Differential Scanning Calorimetry (DSC), optical absorption in the ultraviolet-visible region, Raman spectroscopy and linear refractive index have been achieved. DSC results show a considerable increase in glass stability with the replacement of TeO2 by ZnO. The Band Gap energy, determined from UV-VIS results, gradually increases in all set of samples. The Raman spectroscopy results confirm a structural change: with the increase of ZnO content (until TeO2 = 65 mol%), a decrease of non-bridging oxygens is verified, which decreases the polarizability of the system and increasing the Band Gap energy.