Thermoluminescence characteristics of Zn(BO2)2:Ce3+ under beta irradiation.

Abstract

In this study, the thermoluminescence (TL) characteristics of undoped and various Ce(3) (+)-doped Zn(BO2)2 powder samples excited by beta irradiation are reported for the first time. Zn(BO2)2:Ce(3+) powder samples were prepared by the nitric acid method (NAM) using the starting oxides [zinc oxide (ZnO), boric acid (H3BO3) and doped element oxide (CeO2)]. The formations of the obtained samples were confirmed by an X-ray diffraction study. Dose responses of Ce(3) (+)-doped Zn(BO2)2 samples were investigated after the beta irradiation in the dose range from 143 mGy to 60 Gy. All TL measurements were made on using an automated Risø TL/OSL DA-20 reader. TL emission was detected through a filter pack (Schott BG-39 and Corning 7-59) transmitting between 330 and 480 nm. TL glow curves were obtained using a constant heating rate of 5°C s(-1) from room temperature (RT) to 450°C in an N2 atmosphere. The dose response and minimum detectable dose (MDD) values of the samples were determined. The dose responses of all the samples tested exhibited a superlinear behaviour. MDD value of 4 % Ce(3) (+)-doped Zn(BO2)2 sample, which shows a high temperature peak at about 230°C, was determined as 96 mGy. MDD values for 1, 2, 3, 5 and 10 % Ce(3) (+)-doped Zn(BO2)2 samples were also determined as 682, 501, 635, 320 and 824 mGy, respectively. The trap parameters of undoped and 4 % Ce(3) (+)-doped Zn(BO2)2 samples were estimated by the computerised glow curve deconvolution method.