Thermoluminescent response of Ce- and Li-doped CaF2 phosphor to gamma and UV irradiation

Abstract

In this work, Ce- and Li-doped CaF2 phosphor (CaF2:Ce,Li) was synthesized by the combustion technique. Structural and morphological analysis of the synthesized material has been carried out by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The XRD pattern reveals the formation of a pure phase of the CaF2 crystal with a crystallite size of 717 nm. The luminescence properties were investigated by the thermoluminescence (TL) technique. The effect of sintering temperature on the TL glow curve of the pellets has been investigated for different temperatures (450, 500, 525, 550, and 575 °C). Pellets sintered at 525 °C and 550 °C presented higher sensitivity in their TL responses for gamma and UV irradiation, respectively. Samples irradiated with gamma radiation show two intense TL peaks centered at 172 °C and 275 °C. On the other hand, samples irradiated with UV radiation show two peaks centered at 195 and 280 °C. The intensity of the TL peaks increases with gamma radiation dose and UV irradiation time. The kinetic parameters of the glow curve peaks were determined through the combined analysis of the results obtained by the Tm-Tstop and deconvolution methods.