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The melt-quenching method was used to synthesize the samples of the [(75 − x)B2O3–10TeO2–13SrO–2.0ZnO–xPbO (x = 0.0, 5.0, 10, 15, 25, and 40 mol%)]. The peaks found in the XRD patterns were associated with the crystalline phase, Zn2Te3O8, present in these prepared samples. Substituting B2O3 with PbO resulted in a steady density increase from 2.89 to 4.75 g/cm3. The molar volume (Vm) increased from 30.23 to 31.95 cm3/mol as the concentration of PbO went up from 0 to 40 mol%. The Raman analysis confirmed that the increase in PbO content in the compositions led to a conversion from TeO4 to TeO3 and the change of bridging oxygens to non-bridging oxygens. The optical band gap energy, Urbach energy, and other optical properties were analyzed to determine the optical transmission data. As more PbO was added, the optical band gap energy decreased from 3.140 to 2.930 eV, and the Urbach energy rose from 0.337 to 0.377 eV. Under 300 nm excitation, the photoluminescence spectra showed emission bands linked to electronic transitions of Pb2+. [ABSTRACT FROM AUTHOR]

Glass samples comprising Bi2O3, B2O3, TeO2, MgO, and PbO were fabricated using melt quenching. Substituting B2O3 with Bi2O3 resulted in a steady density increase from 2.88 to 7.16 g/cm3 due to the difference in atomic weight between the heavier Bi (208.98 g/mol) and lighter B (10.811 g/mol). As the Bi2O3 concentration rose from 0 to 60 mol%, the molar volume (Vm) gradually increased from 31.02 to 45.69 cm3/mol, owing to the discrepancy in the radii of the Bi3+ and B3+ ions, measuring 0.96 and 0.84 Å, respectively. Increasing the non-bridging oxygens (NBOs) led to a corresponding rise in the molar volume. Incorporating varying concentrations of Bi2O3, ranging from 0 mol% (BMTPBi0) to 60 mol% (BMTPBi60), induced alterations in several physical parameters, consequently affecting the structural characteristics of the glass. Raman analysis confirmed that an increase in Bi2O3 content within the glass composition led to the conversion of TeO4 to TeO3, resulting in the transformation of bridging oxygens into NBOs. As the Bi2O3 content increased, there was a 3.080–2.090 eV decrease in the optical band gap energy as a result of the rise in NBOs (and consequently, an increase in disorder), leading to a rise in Urbach energy from 0.390 to 0.740 eV. The optimal sample was determined as BTMPBi30 due to its balanced properties and potential advantages. The BTMPBi30 as modifier with heavy metal has high transmittance. The band gap energy of BTMPBi30 (2.920 eV) is reasonable and falls within the range suitable for many optical applications. The Urbach energy increases with Bi2O3 content, and for BTMPBi30 (ΔE = 0.480 eV), it is within an acceptable range, indicating a certain level of disorder. Under 300 nm excitation, the photoluminescence spectra indicate distinct emission bands dependent on the species Bi3+ and Pb2+, making BTMPBi30 a potential candidate for applications requiring photoluminescent properties. [ABSTRACT FROM AUTHOR]

The current work is interested in the preparation, characterization, and mechanical-optical properties of the glasses in the (75-x)B 2 O 3 –10SrO–8TeO 2 –7ZnO−xWO 3 system, with (x = 0 (BSTZW0), 1 (BSTZW1), 5 (BSTZW2), 10 (BSTZW3), 22 (BSTZW4), 27 (BSTZW5), 34 (BSTZW6), and 40 mol% (BSTZW7). The preparation of the glasses has involved the melt-quenching route. The new glasses are characterized by different characterization techniques using densimeter, microhardness, Raman spectroscopy, UV–visible absorption and emission, and X-ray diffraction. Photoluminescence can determine the impact of substituting B 2 O 3 with WO 3 on the mechanical-optical parameters and the structure of the present glasses. The prepared samples' X-ray patterns showed amorphous states. The density value rises from 2.88 to 4.50 g/cm3, with the amount of WO 3 rising from 0 to 40 mol% as a result of the difference in molecular weight between WO 3 and B 2 O 3. The Vickers microhardness (Hv) rises as the amount of WO 3 increases as a result of a decrease in free volume and the formation of covalent bonds. The elastic moduli were found to increase when the WO 3 concentrations increased from 0 to 40 mol%. This increase depends on the formation of bridging oxygen atoms. The Raman bands are designed to correspond to the bonds that form the structure of the current glass and detect the insertion of WO 3 content by the attribution of the new W–O–W and W–O bonds. The UV–Visible spectroscopy analysis showed no band characteristic for the reduced species of W5+ ions identified by dark blue. However, the photoluminescence spectra showed emission bands (under excitation at 300 nm) that are associated with the active centers of W4+, W5+, and W6+ ions. [ABSTRACT FROM AUTHOR]