Experimental investigation of high-density TeO₂- and Sm₂O₃-modified ZnO-BaO-B₂O₃ glasses: Promising lead-free...

The replacement of lead (Pb) in radiation shielding materials is a critical priority for advancing safe medical diagnostics and environmental protection. However, viable alternatives that match Pb's attenuation performance remain limited. In this study, we present a new class of lead-free, high-density glasses: (30-x-y) B₂O₃-9ZnO-31BaO-(30+x) TeO₂-ySm₂O₃, where x = 0, 2, 4, 6 mol% and y = 0, 0.5, 1, 1.5 mol%. These glasses were synthesised via the melt-quenching method. The shielding capabilities of the synthesised glasses were systematically investigated through experimental and Phy-X/PSD theoretical analysis. The experimental arrangement employed a narrow-beam transmission geometry with a NaI(Tl) scintillation detector and radioactive sources including ¹³³Ba, ²²Na, ¹³⁷Cs, and ⁶⁰Co. Gamma-ray attenuation capabilities were evaluated using linear and mass attenuation coefficients (LAC and MAC), half- and tenth value layers (HVL and TVL), mean free path (MFP), and effective atomic number (Z_eff). The results showed that the combined inclusion of TeO₂ and Sm₂O₃ led to a measurable increase in density and gamma attenuation properties across all gamma energies, with strong agreement between experimental and theoretical results, showing a maximum deviation of 8.37 %. The Z_eff ranged from 22.2 at 356 keV to 18.014 at 1332 keV for TeSm-0.5, showing the expected energy-dependent variation due to dominant gamma interaction processes. The HVL and TVL increased with energy but decreased with increasing TeO₂ and Sm₂O₃ contents, with TeSm-1.5 showing the lowest HVL (1.575 cm at 511 keV) and TVL (6.311 cm at 662 keV). These results demonstrate that prepared lead-free glasses achieve substantial shielding efficiency, with potential applications in transparent protective barriers and healthcare infrastructure.