LiZnBO3 phosphor for dosimetry applications

Abstract

This study explores the dosimetric potentials of pristine lithium zinc borate, LiZnBO3, (LZB) phosphor for medical application. The pristine LZB was synthesized by the solid-state reaction (SSR) technique. The structural properties of the synthesized composites were investigated by X-ray diffraction (XRD) and Fourier Transform Infrared (FT-IR) measurements. The FT-IR data shows that the functional groups are responsible for the peak intensity of LZB. The magnetic hysteresis (M-H) loop was characterized using Vibrating Sample Magnetometry (VSM) to distinguish its magnetic characteristics and alterations. From the M-H loop, it behaves as a superparamagnetic material. A clinical Linear Accelerator (LINAC) was used to irradiate the samples with both electron (6 MeV) and X-ray photon beam (6 MV), with a dose range of 0.5 Gy–8 Gy for both beams. The experiment was designed to study low to medium-dose TL response for LZB. The irradiated samples were readout for thermoluminescence (TL) signal using a Harshaw-3500 TL reader with a fixed heating rate of 10 °C/s. The TL kinetic parameters of the composites were studied by analysing the glow curves using the peak-shape method. The geometric factor (μg) is found to be within the range of 0.42–0.52, which indicates the suitability of applying Chen's general-order formula to calculate kinetic parameters. The activation energy (E) is found in the range of 1.13–3.14 eV for 4 deconvoluted peaks of 6 MeV electron beam irradiation and 1.82–2.16 eV for 3 deconvoluted peaks of 6 MV X-ray photon beam irradiation. The frequency factor (s) also increases while activation energy increases for both electron and X-ray photon beams. All the obtained results confirm the suitability of LZB phosphor to develop a viable radiation dosimeter.