Synthesis, physical, optical and gamma radiation shielding capacities of novel mercuric-sodium-lead-borate glasses

Abstract

The influence of mercuric oxide (HgO) on structural, physical, optical, and radiation shielding capacities of newly developed glasses with nominal compositions (55-x)B2O3·10SrF2·25PbO·10Na2O·xHgO: x = 0, 2, 4, 6, and 8 mol% has been investigated. Hg-glasses were synthesized by the traditional melt quenching technique and coded as Hg0, Hg2, Hg4, Hg6, and Hg8, respectively. The amorphous nature of Hg-glasses was confirmed via XRD measurements. Density of the prepared glasses was measured via Archimedes' method and it was increased from 4.59 g/cm3 for Hg0 sample to 5.20 g/cm3 for Hg8 sample. The values of optical band gap (Eg) were reduced with the insertion of HgO in Hg-glass network. The direct (Eg) was changed from 3.52 to 3.21 eV, while the indirect one change from 2.47 to 2.14 eV. Urbach's energy (Eu) was varied from 0.737 to 1.544 eV and refractive index was improved from 2.197 to 4.077 at wavelength λ=500 nm. The average oscillator strength (So) of Hg-glasses was changed from 2.885×10-5 (nm)2 to 11.078 × 10−5 (nm)2. The Hg8 glass possessed the maximum values of mass attenuation coefficient (MAC)Phy-X/PSD among all Hg-glasses. The values of (MAC)Phy-X/PSD at (0.015 MeV, 15 MeV) were (0.037, 53.675), (0.38, 58.123), (0.039, 62.352), (0.40, 66.376), and (0.40, 70.210) cm2/g for Hg0, Hg2, Hg4, Hg6, and Hg8 glasses, respectively. The variation of the effective atomic number (Zeff)Phy-X/PSD of the prepared Hg-glasses has a similar trend of (MAC)Phy-X/PSD. The half value layer (HVL)Phy-X/PSD for various samples followed the trend; ((HVL)Phy-X/PSD)Hg0 > ((HVL)Phy-X/PSD)Hg2 > ((HVL)Phy-X/PSD)Hg4 > ((HVL)Phy-X/PSD)Hg6 > ((HVL)Phy-X/PSD)Hg8. However, the reduction of (HVL)Phy-X/PSD with increasing HgO concentration in the glassy system increase its ability to shield against the incident photons. The prepared Hg-glasses with improved physical and optical properties can be used in various optical applications and are superior as radiation shielding materials than seven kinds of concrete OC, HSC, ILC, BMC, IC, SSC, SMC, and RS-253-G18 glasses.