Tailoring optical and radiation shielding properties of manganese lead borate glasses via silver iodide modification

Abstract

This study investigates the structural and physical modifications induced by the incorporation of silver iodide (AgI) into a borate glass matrix. A glass series with the general formula ((75-x) B<inf>2</inf>O<inf>3</inf> + 20PbO + 5MnO<inf>2</inf> + xAgI), where 0 ≤ x ≤ 2.0 mol% in increments of 0.5 mol%, was synthesized. The glass samples were examined using Fourier transform infrared (FT-IR), optical spectroscopy, density measurements, and other analytical tools. Furthermore, the radiation shielding proficiency of the investigated glass system was evaluated through Monte Carlo simulations and Phy-X software, focusing on parameters such as the linear attenuation coefficient (μ), mass attenuation coefficient (μ<inf>m</inf>), half value layer (HV), etc. Experimental results revealed that increasing the AgI content from 0 to 2.0 mol% led to a 7.7% linear increase in density, rising from 3.12 to 3.36 g/cm³, while the molar volume decreased from 32.4 to 31.1 cm³/mol. FT-IR analysis indicated that AgI acts as a lattice modifier, facilitating the conversion of BO<inf>4</inf> units to BO<inf>3</inf> units and subsequently increasing the concentration of non-bridging oxygens (NBOs). These structural changes, alongside heightened internal lattice disorder, resulted in a reduction of 3.04% of the optical band gap from 2.96 to 2.87 eV. Optical spectra further demonstrated that Ag⁺ ions influence the coordination of manganese, favoring the transition of Mn²⁺ ions from tetrahedral to octahedral sites. Shielding analysis confirmed that the linear attenuation coefficient follows the order: BPbMnAg0.0 < BPbMnAg0.5 < BPbMnAg1.0 < BPbMnAg1.5 < BPbMnAg2.0. Additionally, calculated effective removal cross-sections indicated that increasing AgI concentrations significantly enhance fast neutron removal capacity. These findings suggest that AgI-doped manganese lead borate glasses are highly effective candidates for advanced photon and neutron shielding applications.