Optical and radiation shielding features for some phospho-silicate glasses

Abstract

Glass composition comprising of SiO2-Na2O-K2O-P2O5 with CaO/BaO were synthesised and characterized using XRD and UV-Vis spectroscopy. The optical features were analysed in terms of band gap (E-g), refractive index (n), molar refraction (R-M), molar polarizability (alpha(m)), reflection loss (R-LOSS), optical transmission (T-Optical), metallization criterion (M-criterion), dielectric constant (epsilon(Static), epsilon(Optical)), optical electronegativity (chi) and optical basicity (Lambda). The E-g of glasses acquired using Tauc's plot and ASF methods authenticates the applicability of both methods as equally good. The E-g value decreases, whereas n increases with an increase in alkaline earth metal oxides (CaO/BaO) content in the glass samples. The M-criterion exhibits metallic nature of the glasses. The R-M and alpha(m) decreases as CaO/BaO content increases; whereas R-LOSS and T-Optical remains constant for the glasses. The dielectric constants increase as CaO/BaO content increases. The photon attenuation parameters were investigated using MC simulations (PHITS and GEANT4) and theoretically using WinXCom. Among all glasses, S8 glass sample has highest mu/rho, mu, Z(eff), N-eff and lowest mfp values. Further, S8 glass has low values of both stopping power (S-P) and range (R-p); as required for shielding from charged particles. The slow and fast neutron shielding ability also escalates with an increase in CaO/BaO content in glass matrix. Comparative analysis confirms that S8 glass sample possess superior radiation shielding competency not only for neutral radiations (photon and neutron beams), but also for charged particles (e, p, alpha and C-ion beams) as compared to several commercial shielding materials.