Effects of mixed TeO₂-B₂O₃ glass formers on optical and radiation shielding properties of 70[xTeO₂+(1−x)B₂O₃]+15Na₂O + 15K₂O glass system

In the present work, the optical properties and gamma-ray shielding properties of 0[xTeO₂ + (1−x)B₂O₃] + 15Na₂O + 15K₂O glasses have been investigated. The optical band gap (E_opt) showed an initial decrease for x ≤ 10 mol% and then increased for x >10 mol%, which is suggested to be related to the changes in concentration of non-bridging oxygen (NBO). Urbach energy (E_u) behaves inversely with E_opt Within the same region, refractive index (n) also exhibited an off-trend pattern that signified polarizability difference led by alteration in bridging oxygen and NBO concentration. The mass attenuation coefficient (MAC) derived from interpolation of EPICS2017 in ENDF/B-VIII were in good agreement with generated values of XCOM and showed a decreasing trend with increasing gamma photon energy from 59.5 keV to 1333 keV. The linear attenuation coefficient (LAC) also showed a decreasing trend with the increase in energies from 59.5 to 1333 keV, which indicates that the prepared TeO₂-B₂O₃-Na₂O-K₂O glasses can effectively shield the low energy photons, while this ability to shield the photons becomes weaker with increasing energy. The results revealed that the sample with no TeO₂ has a relatively higher mean free path (MFP) compared to other samples, and the addition of TeO₂ highly affects the MFP values. Thus, the glass with no TeO₂ requires a much higher thickness than the remaining glasses to attenuate the photons and to provide sufficient protection from radiation. (author)