Thermally stimulated luminescence studies for dysprosium doped strontium tetraborate

Abstract

In this paper TL studies of Dy 3 + doped SrB 4 O 7 compound are reported by β -ray irradiation for the first time. The polycrystalline powder samples of dysprosium doped SrB 4 O 7 :Dy phosphor were prepared by a solid-state reaction in air at high temperature and the TL glow curves and TL emission spectrum after β -ray irradiation was studied from 50 to 250 kGy dose range. The TL studies of Sr 0.93 Dy 0.07 B 4 O 7 sample show main TL glow peak at 497 K, and the 497 K glow peak show great stability for a long time. The trap parameters namely activation energy ( E ) , order of kinetics ( b ) , and frequency factor ( s ) of main peak of the Sr 0.93 Dy 0.07 B 4 O 7 sample at 497 K were determined using glow curve shape (Chen's) methods. The TL emission bands at about 480, 575, 660 and 750 nm of the SrB 4 O 7 :Dy phosphor is attributed to the characteristic emission from f–f transitions of Dy 3 + ion. The distributions of trap produced by the irradiation of β -ray can be altered greatly by the change of the concentrations of Dy 3 + ion doped in SrB 4 O 7 host and, all peak temperatures shift to higher temperature, this will be favorable for TL output. The TL-dose response of the SrB 4 O 7 :Dy polycrystalline powder sample to β -ray radiation in the range from 50 to 250 kGy for radiation processing dose levels is almost linearity. The experiment results showed that SrB 4 O 7 :Dy potential use as the materials of β -ray thermoluminescence dosimeter (TLD) for radiation processing dosimetry.