Multifunctional PbO2-Based borate glasses: Tailoring mechanical, optical, and radiation shielding capabilities through composition control

This study synthesized four glasses using melt-quenching with the composition xPbO 2 -(66-x)B 2 O 3 -22BaO-9CaO-3Y 2 O 3 (x = 11, 14, 17 and 20 mol%) to evaluate their physical, mechanical, optical, and radiation shielding properties. Density and molecular weight rose from 4.312 to 4.800 g cm -3 and 110.155 to 125.418 g mol -1 with increasing PbO 2 , due to its higher atomic mass. Mechanical properties Young's modulus (91.422-81.473 GPa) and micro-hardness (4.733-4.484 GPa) declined with PbO 2 addition, attributed to reduced bond strength and compactness. Optical band gaps (direct: 2.931-2.849 eV, indirect: 2.478-2.296 eV) decreased up to 17 mol% PbO 2 , while Urbach energy rose from 0.347 to 0.414 eV, indicating more non-bridging oxygens. Refractive index increased (2.558-2.668), and Metallization values dropped (0.351-0.329), suggesting reduced insulating nature. Radiation shielding was evaluated in the energy range of 0.015-15 MeV using Phy-X software. Pb20Y3 showed superior shielding due to highest PbO 2 . LAC at 0.015 MeV rose from 186.392 to 261.730 cm -1 ; HVL at 1 MeV dropped from 2.557 to 2.252 cm; TVL at 0.4 MeV reduced from 4.048 to 3.243 cm. Z eff peaked at 63.28 for Pb20Y3 at 0.015 MeV. Compared to other glass systems, the prepared glasses exhibited enhanced shielding, highlighting the potential of PbO 2 -rich glasses for optical and radiation protection applications.