Thermoluminescence features of Er3+ doped BaO-ZnO-LiF-B2O3 glass system for high-dose gamma dosimetry

Abstract

Transparent 10BaO-20ZnO-20LiF-(50-x) B2O3-xEr2O3 glasses with x = 0, 0.1, 0.5, 0.7 and 1 mol % were synthesized using melt-quench method. Their amorphous nature was confirmed from X-Ray Diffraction (XRD). The glasses were irradiated with 3 kGy gamma dose, among which the sample with 0.7 mol % Er2O3 doping showed the highest integrated thermoluminescence (TL) intensity. The dose-response was evaluated by irradiating the sample with 0.25- 30 kGy gamma doses. The highest integrated TL intensity was obtained at 3 kGy dose. Fourier Transform Infrared (FTIR) spectra of the 0.7 mol % Er2O3 doped glass after 3 kGy gamma irradiation predicted the creation of new bonds and rise in the Non-Bridging Oxygens. UV–Vis–NIR absorption spectra recorded after 3 kGy gamma irradiation accounted for the formation of color centers due to an increase in the total absorption of the glass, a decrease in the bandgap and an increase in the Urbach energy. The sample exhibited good linearity in the 0.25 to 3 kGy range with high sensitivity of 27021 counts g-1kGy-1 and a minimum detectable dose of 0.201 kGy. TL signal faded by just 4% after a week of storage. The annealing condition for reusability and the effective atomic number of the glass were examined. Trap parameters like activation energy, frequency factor and lifetime, determined using Computerized Glow Curve Deconvolution (CGCD) and Chen's peak shape methods supported the low fading of the sample. Overall, the remarkable TL dosimetry characteristics present the usefulness of the titled glass system in radiation processing of food products and high-dose (0.25 to 3 kGy) gamma environment.