The role of La, Eu, Gd, and Dy lanthanides on thermoluminescence characteristics of nano-hydroxyapatite induced by gamma radiation

Thermoluminescence response of hydroxyapatite doped with different percentages of lanthanide elements comprises La, Eu, Gd, and Dy has been studied under the action of gamma radiation. The samples were synthesized through hydrolysis method. The irradiations were done using a 60Co γ-ray source over a dose range of 25 Gy–1 kGy. The results showed that the samples have different response intensities among which mostly belonged to Dy-doped hydroxyapatite samples. The effect of dopant concentrations on the thermoluminescence intensity was also investigated. The Tm–Tstop experimental method and TLanal program were used to analyze the glow curves of the doped samples and obtain their kinetic parameters. The frequency factors and the activation energies were also obtained for different samples. The contribution of the sub-peaks was found through deconvolution procedure in the thermoluminescence responses, and the fading behaviors are also discussed. The results showed that the thermoluminescence characteristic of nanostructure hydroxyapatite sample containing 1 m% of Dy concentration has the privilege of using as a candidate for gamma radiation dosimetry.