Thermal,FTIR and UV spectral studies on tellurite glasses doped with cerium oxide

Tellurium oxide-based glasses in the form of 75TeO₂ – 10ZnO – (10-x)Nb₂O₅ – 5Li₂O – xCe₂O₃; where x = 0.5, 1, 1.5, 2, 2.5 mol%, were prepared by using the melt-quenching method. X-Ray Diffraction pattern (XRD) detected the amorphous nature of all the prepared glasses. Physical properties like density (ρ), molar volume $(V_m)$, and oxygen packing density (OPD), have been determined and calculated. Fourier transform infrared spectroscopy (FTIR) studies showed that the glass network contains TeO₄, TeO₃₊₁/TeO₃, ZnO₄, and NbO₆ as structural units. The glass transition temperature (T_g), onset of glass crystallization temperature (T_x), crystallization temperature (T_c), and melting temperature (T_m) have been determined by using differential scanning calorimetry (DSC). The optical band gap (E_opt), the Urbach energy (?E), and the cut off wavelength (λc) were determined through the optical absorption data.