Thermoluminescence dosimetric characteristics of thulium doped ZnB2O4 phosphor

Polycrystalline powder samples of rare earth doped Zinc borates were synthesized by high temperature solid state diffusion technique. Dosimetric characteristics of the phosphor like thermoluminescence glow curve, TL emission spectra, dose–response, fading studies, reproducibility and reusability studies were carried out on the synthesized phosphors. Among the different rare earth doped phosphors, thulium doped zinc borate was found to have a higher sensitivity. Hence detailed dosimetric characteristics of this phosphor were carried out. It is observed that the dose–response is linear from 10mGy to 103Gy in this phosphor. EPR measurements were carried out on unirradiated, gamma irradiated and annealed phosphors to identify the defect centers responsible for thermoluminescence. A TL model is proposed based on the EPR studies in these materials. Kinetic parameters were evaluated for the dosimetric peaks using various methods. The experimental results show that this phosphor can have potential applications in radiation dosimetry applications. •Polycrystalline powder samples of rare earth doped zinc borates were synthesized.•Thulium was observed to be the most efficient dopant in ZnB2O4 lattice.•TL intensity of the dosimetric peak is around 20 times that of TLD-100.•Based on EPR studies a TL mechanism is proposed in zinc borate.•Deconvolution of the glow curve carried out.