Advanced optical and gamma-ray shielding behavior of Bi2O3-doped molybdenum iron borosilicate glasses

Abstract

Glasses with the structure 18SiO₂–42B₂O₃–13MoO₃–2Fe₂O₃-(25-x)Li₂O-xBi₂O₃, where x=(0, 2, 4, 8, and 10 mol. %) were synthesized. The density (ρ) increased systematically from 2.88 to 3.69 g/cm³ with the rise in Bi₂O₃ content. Their optical absorption properties were systematically investigated. In addition, the effect of structural modifications within the glass network was analyzed in detail, revealing how these changes contribute to the enhancement of the optical performance of the prepared glasses. The red shift in the absorption edge, along with the increased proportion of (NBOs), is considered the primary cause for the reduction in the optical band gap. Calculations of the optical band gap revealed a decreasing trend with increasing Bi₂O₃ content, indicating an increase in structural disorder. In the studied glass samples, the elastic moduli exhibit a decreasing trend with increasing Bi₂O₃ concentration. The shielding parameters against radiation were assessed. Results showed that the half-value layer (HVL) and mean free path (MFP) decreased progressively. The higher Bi₂O₃ content is responsible for its superior shielding performance. These findings demonstrate that the samples are effective radiation shielding materials.