Dosimetric characterization for optimum concentration in rare earth doped hafnium oxide nanophosphors for medical radiotherapy applications

Abstract

Rare earth (RE) doped HfO2 NPs was prepared using the co-precipitation method. This study focuses on the dosimetric characteristic of rare earth (Gd3+,Eu3+,Ho3+) activated HfO2 nanoparticles as potential thermoluminescence (TL) dosimeter for radiation therapy dosimetry. The selected dopant concentrations of 2.5 mol% of Gd, 7.5 mol% of Eu and 2.5 mol% of Ho were irradiated with a clinical gamma photon beam. From the study of dosimetric characterization, it is observed that there is an enhancement of dose response by incorporating rare earth materials. The results obtained in this work show that the Eu3+(7.5 mol%) satisfies the dosimetric characteristic (expect fading) other than an optimized dopant concentration of Gd and Ho. Eu3+ showed that the dosimetric features of reproducibility are high, the linear behavior for photon dose is a good and high degree of fading. The fading factors for the proposed dosimeters at room temperature, which explicit the high loss of TL signal is due to the un-stabilization of trapped charged effects. This detailed study can be useful for the further development of highly efficient ionizing radiation dosimetry.