Zinc borate glasses have experienced growing attention recently owing to their remarkable combination of optical, thermal, and chemical characteristics. Nevertheless, certain drawbacks in its optical performance persist, particularly a reduction in the optical band gap caused by the incorporation of high concentrations of heavy metal oxides. Hence, a new composition in the bismuth zinc borate glass, xBi2O3-(45-x)ZnO-55B2O3, was fabricated using the conventional melt-quenching method. The density and molar volume increased from 3.19 to 4.28 g/cm3 and 23.48 to 31.00 cm3/mol, respectively. Simultaneously, the direct and indirect band gaps decreased, shifting from 3.51 eV to 1.48 eV and from 3.28 eV to 0.92 eV, respectively. The estimated refractive index increased from 2.27 to 3.00 with increasing Bi2O3 concentration. Notably, the highest optical transmittance was observed in the glass containing 1 mol% Bi2O3, which also exhibited the highest PL intensity, with an emission maximum at 521 nm. Radiation-shielding parameters were systematically evaluated over a broad photon-energy range using Phy-X/PSD simulations. Increasing Bi2O3 content enhanced the radiation attenuation performance, with the 15 mol% Bi2O3 glass exhibiting the highest shielding capability. Overall, the results demonstrate a trade-off between optical and radiation-shielding performance, indicating that low Bi2O3 content favors optical performance, whereas higher Bi2O3 content provides superior radiation attenuation. These glasses, therefore, show potential as lead-free multifunctional materials for optical and radiation-shielding applications.
This work investigates the role of sintering temperature on bioactive glass-ceramics derived from the new composition CaO-P2O5-Na2O-B2O3-SiO2 glass system. The sintering behaviour of the samples' physical, structural, and mechanical properties is highlighted in this study. The experimental results indicated that the sintering process improved the crystallization and hardness of the final product. Results from XRD and FTIR showed the existence of carbonate apatite, pseudo-wollastonite, and wollastonite phases. From the results, the bioglass-ceramics sintered at 700 °C obtained the highest densification and optimum mechanical results. It had the value of 5.34 ± 0.21 GPa regarding microhardness and 2.99 ± 0.24 MPa m1/2 concerning fracture toughness, which falls in the range of the human enamel. Also, the sintered samples maintained their bioactivity and biodegradability after being tested in the PBS medium. The bioactivity does not affect but slows down the apatite formation rate. Overall results promoted the novel bioglass-ceramics as a candidate material for dental application.