Thermoluminescence of hydroxyapatite from eggshell powders doped with Dy synthesized by the sonication chemical method: Effects of doping concentration and heating rate

Abstract

Hydroxyapatite (HAP) was selected as the host material and synthesized using a sonication chemical method. The effect of Dy3+ ion doping concentrations (0.25, 0.5, 1, 2, 3, 4, 5, 7, and 10 wt%) on the structure and thermoluminescence was examined. The TL properties of Dy3+ doped HAP were also studied, including dose response, repeatability, and heating rate. Based on the glow curves of samples with a heating rate of 2 degrees C/s after beta irradiation to 20 Gy, three effective peak maxima appeared to make up the glow curves located at around 84, 190, and 318 degrees C. However, four levels of activation energy were observed by Tm-Tstop analysis. The kinetic analysis of four peaks obtained via computerized glow curve deconvolution revealed trap depths of 0.80, 0.95, 1.20, and 1.51 eV, with corresponding frequency factors of 1010, 1011, 1012, and 1011 s-1, respectively. Parallel investigations using the initial rise and variable heating rate approaches yielded comparable trap depth esti-mates. The dose dependence of the glow curves was determined to be linear across the 0.1-20 Gy range.