Newly developed CeO2 and Gd2O3-reinforced borosilicate glasses from municipal waste ash and their optical, structural, and gamma-ray shielding properties

Abstract

From the useless municipal solid waste (MSW) ashes, CeO₂, Gd₂O₃ and CeO₂ + Gd₂O₃ doped borosilicate glasses were organized via melting-quenching procedure. Various optical, structural, physical and radiation shielding parameters were examined towards the influence of 100 kGy of γ-radiation. UV-visible NIR spectra revealed UV peaks at 351, 348 and 370 nm corresponding to the trivalent states of Ce³⁺ and Gd³⁺ ions, while, photoluminescence (PL) spectra displayed asymmetric broad excitations of Ce³⁺ and Gd³⁺ ions due to 4f → 5d transitions, and emission intense bands at 412, 434, and 417 nm. CIE chromaticity shows that Gd³⁺ ions increase the luminescence of Ce³⁺. FTIR absorption bands revealed an overlapping between tetrahedral groups of silicate (SiO₄), with trigonal (BO₃) and tetrahedral (BO₄) units of borate. The influence of 100 kGy obtains quite reduction in UV-visible NIR and PL peaks, large stability in FTIR and ESR spectra, and stability of thermal expansion coefficient (CTE) as well. The whole data revealed optical, structural and physical stability of glasses after irradiation besides an enhancement in microhardness owing to more structural compactness and high bonding connectivity. Radiation shielding parameters from Phy_-X/PSD program showed higher values of mass (MAC) and linear attenuation coefficients (LAC), and effective atomic number (Z_eff) in the order of; glass _Ce+Gd > glass _Ce > glass _Gd. Ce + Gd doped glass revealed also the lowest half value layer (HVL) comparing to other shielding commercial concretes. The study recommends the beneficial and economical use of the useless MSW ash to produce CeO₂ and/or Gd₂O₃ borosilicate glasses with hopeful radiation shielding features.