Afterglow dosimetry performance of beta particle irradiated lithium zirconate

Abstract

In this work, we report for the very first time on the thermoluminescence (TL) and afterglow (AG) properties of Li₂ZrO₃. The ternary oxide Li₂ZrO₃ was synthesized by solid state reaction of a mixture of Li₂CO₃ and ZrO₂ subjected to thermal annealing at 400°C for 2h and 1000°C during 24h in air. The characteristic glow curves of beta particle irradiated samples exhibit an intense TL emission located around 150°C. From the shape of the TL curve, a 0.4 form factor was determined, suggesting that first order kinetics processes are involved. The afterglow decay curves were recorded after exposure to beta particle irradiation in the dose range from 0.5 up to 2kGy. The AG integrated in the time interval from 510 to 600s after radiation exposure shows a linear dependence as a function of the irradiation dose from 0.5 up to 256Gy. A method is proposed to compute the lower detection limit and the AG sensitivity and applied to the studied phosphors. Structural and morphological characterization were carried out by X-ray diffraction and Scanning Electron Microscopy, respectively. From the results presented, it is concluded that the AG response of the synthesized Li₂ZrO₃ presents features suitable to develop radiation detectors and dosimeters.

Keywords: Afterglow dosimetry; Beta particle irradiation; Li(2)ZrO(3).