Optical, thermal, and radiation shielding characterization of bismuth-modified zinc-lithium-tungsten-borate glass

This study examines the optical, thermal, and radiation attenuation properties of zinc-tungsten-lithium-borate glass modified with Bi₂O₃, synthesized using melt-quench techniques. The resulting glass samples display a significant physical property, with density increasing from 3.22 g cm⁻³ to 4.84 g cm⁻³ as Bi₂O₃ concentration increase from 2 to 16 mol%. The optical band gap narrows from 2.9 eV to 2.55 eV, while the refractive index increases from 2.42 to 3.49, indicating a shift in absorption to lower energy levels. Higher Bi₂O₃ concentrations reduce optical non-linearity while enhancing the linear optical properties of the synthesized glasses. The formation of orthoborate anions suggests that Bi³⁺ ions in the glasses act as network modifiers, disrupting the borate framework and introducing structural disorder. Additionally, thermal properties, including glass transition temperature ( T g ), crystallization temperature ( T c ), and melting temperature ( T m ), decrease with increasing Bi₂O₃ concentration. The radiation shielding effectiveness is significantly improved, with the linear attenuation coefficient (LAC) increasing from 0.56 cm⁻¹ to 1.35 cm⁻¹ at 0.284 MeV and from 0.127 cm⁻¹ to 0.186 cm⁻¹ at 2.506 MeV as Bi₂O₃ content rises from 2 mol% to 16 mol%. For a glass thickness of 1 cm, the radiation protection efficiency reaches approximately 74% for a photon energy of 0.284 MeV in the sample doped with 16 mol% Bi₂O₃. The glass’s remarkable combination of high transparency and effective radiation attenuation, positions it as a promising option for radiation shielding applications.