Preparation, characterization, and mechanical-optical properties of telluro-borate glasses containing tungsten

Abstract

The current work is interested in the preparation, characterization, and mechanical-optical properties of the glasses in the (75-x)B2O3–10SrO–8TeO2–7ZnO-xWO3 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 B2O3 with WO3 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 WO3 rising from 0 to 40 mol% as a result of the difference in molecular weight between WO3 and B2O3. The Vickers microhardness (Hv) rises as the amount of WO3 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 WO3 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 WO3 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.