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The DC conductivity of Eu3+ ions embedded in lead boro-tellurite glasses has been accomplished as a function of temperature in the range of 343–483 K. The Cole-Cole (Impedance) plots of glasses contained only one perfect semicircle at different temperatures. This realizes the material's conductivity which presumes an ideal Debye type relaxation. In the Cole-Cole plot at 483 K, the semicircle is well defined and fitted into an equivalent parallel RC circuit. The DC conductivity exhibits the Arrhenius behavior and compositional dependence. The DC activation energy (Edc) was estimated for all samples by using linear regression analysis. The values range from 0.202 to 0.231 eV.

Six glass samples composes the (70-y) B2O3-15TeO2-10Na2O-5PbO-yEu2O3, where y = 0.0, 0.1, 0.2, 0.3, 0.4, and 0.5 mol%, have been synthesized by conventional melt quenching technique. The properties such as the structural, thermal and spectroscopic properties were studied by employing the suitable characterizations tools, such as X-ray diffraction, differential scanning calorimetry, Raman spectroscopy, fourier transform infrared spectroscopy, magic angle spinning nuclear resonance spectroscopy, scanning electron microscopy, and energy dispersive X-ray spectroscopy. The XRD, SEM and EDS confirm non-crystalline nature, microstructural and homogeneous, absence of impurity of glass samples, respectively. The DSC data reveals the good thermal stability of glasses. The FT-IR and Raman studies reveal the contribution of boron and tellurium in the network of prepared glasses, the presence of BO3, and BO4, a small amount of six-member boroxol rings, TeO3 and TeO4 structural groups. The MAS-NMR studies reveal the presence of quadrupolar interaction of BO4 and quadrupolar broadening of BO3 in all glasses and it also discloses the fact that only a small amount of BO4 is converted into BO3 during structural evolution.

Lead boro-tellurite glasses activated with europium oxide were synthesized with the aid of conventional melt quenching mode. Physical properties such as density and molar volume as a function of Eu2O3 concentration were determined. Structural studies have been done through X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FTIR). Morphological and luminescent properties have been analysed with Scanning Electron Microscopy (SEM) and spectrofluorometer, respectively. Non-crystalline character was proved by XRD and the surface morphology by SEM technique. Five luminescence emission bands were observed at different wavelengths when excited by 394 nm. The most intensive emission peak was positioned at 612 nm (red) due to 5D0 →7F2 transition of Eu3+ ion. Judd-Ofelt (JO) theory was applied to estimate various radiative parameters and to decide the suitability of the glass for technological applications. JO and the CIE Chromaticity values reveal the investigated glasses are promising materials for electro-optic applications.

The influence of Eu3+ ions on the Optical properties of Boro Tellurite Glasses of (70-x) B2O3−15TeO2−10Na2O− 5PbO-xEu2O3 with x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and their physical and optical properties were investigated by using UV absorption spectra, which was recorded at room temperature in the UV-visible region of wavelength 200-1100 nm. By the absorption edge studies, the values of optical bandgap energies have been evaluated. The direct and indirect bandgap values ranges between 3.362 to 3.650 eV and 2.011 to 2.863 eV respectively. The refractive index, molar refraction and polarizability of oxide ions have been calculated by using Lorentz–Lorentz relations. The refractive index and molar refraction values were ranges from 2.241 to 2.358 and 76.147 to 79.915 cm3 respectively. The non-linear variations of the above optical parameters were discussed with respect to small variation of europium (Eu3+) ion concentration.The influence of Eu3+ ions on the Optical properties of Boro Tellurite Glasses of (70-x) B2O3−15TeO2−10Na2O− 5PbO-xEu2O3 with x = 0, 0.1, 0.2, 0.3, 0.4 and 0.5 mol% glasses were prepared by conventional melt quenching method and their physical and optical properties were investigated by using UV absorption spectra, which was recorded at room temperature in the UV-visible region of wavelength 200-1100 nm. By the absorption edge studies, the values of optical bandgap energies have been evaluated. The direct and indirect bandgap values ranges between 3.362 to 3.650 eV and 2.011 to 2.863 eV respectively. The refractive index, molar refraction and polarizability of oxide ions have been calculated by using Lorentz–Lorentz relations. The refractive index and molar refraction values were ranges from 2.241 to 2.358 and 76.147 to 79.915 cm3 respectively. The non-linear variations of the above optical parameters were discussed with respect to small variation of europium (Eu3+) ion concentration.