Synthesis and thermoluminescence characteristics of beta irradiated nanocrystalline calcium aluminate doped with lanthanum oxides

Abstract

This study investigated the thermoluminescence (TL) characteristics of calcium, a nano-phosphor doped with a rare earth element (lanthanum, La). Six different concentrations of dopants were prepared by the sol-gel method. The XRD data displayed that the particle size was 52.48 nm. The surface morphology was examined by SEM analysis. The highest TL response of the nano-phosphor CaAl2O4 was found with a dopant of 0.1 % La, which has the most intense TL peak. The Computerized Glow Curve Deconvolution (CGCD) and Variable Heating Rate (VHR) methods were carried out for trap-level analyses and activation energy determination. The deconvolution of the glow curves displayed thirteen superimposed TL glow peaks located between 362 and 717 K. The TL response of CaAl2O4:0.1 % La nano-phosphor showed linearity in the beta dose range from 2.2 Gy up to 330 Gy for all the deconvoluted glow peaks. The minimum detectable dose of the prepared samples is 284 μGy. Other parameters, such as the sensitivity and reproducibility of the prepared samples, were determined. It is concluded that CaAl2O4 with a dopant of 0.1 % La is a good material for dosimetry applications.