Physical, optical, thermal, and gamma-ray shielding features of fluorotellurite lithiumniobate glasses: TeO_2-LiNbO_3-BaO-BaF_2-La_2O_3

摘要

Novel series of fluorotellurite lithium niobate glasses with compositions TeO_2-LiNbO_3-BaO-BaF_2-La_2O_3 coded as Pr3, Pr4, Pr5, Pr6, and Pr7 were fabricated using the traditional process of quenching the melt. The density of the fabricated glasses was varied from 5.1689 to 5.4088 g/cm~3, while optical packing density (o.p.d) was taken values from 50.85 to 64.4 g atom 1~(-1). The thermal features glasses were determined by using (DSC), while their optical properties were determined in ultraviolet-visible-near-IR (UV-Vis-NIR) spectral region. Results revealed that the glass transition temperature (T_g) has the lowest value for Pr6 glass sample otherwise the highest value in Pr3 sample. The thermal stability (ΔT) was equal to 133, 149,154,127, and 153 °C for Pr3, Pr4, Pr5. Pr6, and Pr7 glass samples, respectively. The optical energy gap (E_(opt)) varied from 2.81 to 3.12 eV, while the Sellmeier gap energy (E_s) changed from 6.6 to 8.55 eV. Also, gamma-ray shielding competences of the fabricated glasses were evaluated in terms of their mass and linear attenuation coefficients (MAC, LAC), half-value layer (HVL), and mean free path (MFP). The obtained values showed that LAC was in the order of Pr7 ＞ Pr6 ＞ Pr3 ＞ P4 ＞ Pr5, while HVL arranged in the order of Pr7 ＜ Pr6 ＜ Pr3 ＜ Pr4 ＜ Pr5. Therefore, Pr7 glass has the highest LAC and the lowest HVL which assured its best shielding capacity among all the proposed glasses.