Role of Gd³⁺ ions in alumino borosilicate glasses studied through structural, optical and thermoluminescence characteristics for gamma dosimetry applications

This paper reports the structural, optical and thermoluminescence properties of Gd³⁺ ions incorporated alumino-borosilicate glasses, prepared through the melt-quench technique. The amorphous nature of the glasses is confirmed through XRD study. Network vibrations of borate and silicate groups, vibrations of hydrogen bonding and hydroxyl groups are realized via FTIR study. The Gd³⁺ transition peaks are absent in the near ultraviolet, visible and NIR regions, and the indirect bandgap values were determined through UV–Visible–NIR study. Photoluminescence measurements showed a concentration quenching in the glasses beyond 1.5 mol % of Gd³⁺ ions. Based on the thermoluminescence (TL) data, the 2 mol % of Gd₂O₃ doped glass (BSGD5) was chosen as optimum sample because of the presence of maximum TL intensity. The BSGD5 glass displayed TL response linearity in 0.25–1 kGy dose region giving a high signal sensitivity of 220,068 counts. g⁻¹ kGy⁻¹ in this region. With nearer tissue equivalence and a minimum detectable dose of 0.02 Gy, the suitability of BSGD5 glass for gamma dosimetry application was deducted. Electron spin resonance (ESR) study validated the presence of intrinsic defects in Gd³⁺ glasses which are responsible for changes in the intensity and shape of TL glow curves. Hence, from the obtained results Gd³⁺ doped alumino borosilicate glasses can be considered as potential candidates for gamma dosimetry application.