Development of new sensitive thermoluminescent materials for radiation dosimetry

In this work, the thermoluminescent properties of undoped, and rare earth and metallic elements doped some alkaline earth borates were studied. The following materials BaB4O7, LiB3O5, Li2B4O7, MgB4O7 and CaB4O7 were synthesized by solid state and melting methods in air condition. The X-ray diffractometer method was firstly used to characterize and identify the products and then the various metals and rare earth elements were doped to enhance the thermoluminescence (TL) sensitivity of developed materials. Some of the TL properties of developed phosphors were studied in detail. Comparative TL studies of these compounds were shown that the Ce-doped BaB4O7 and Al-doped LiB3O5 compounds have higher TL sensitivity than the others. In addition, after the investigation of TL properties of Ce-doped BaB4O7 and Al-doped LiB3O5 samples, they seem as a good promising TL detector for different dosimetric applications owing to its simple glow curve structures with high sensitivity, the absence of thermal fading even at elevated temperatures, reduced light sensitivity, re-usability with excellent reproducibility and chemical stability. Therefore, it was assumed that the obtained Ce-doped BaB4O7 and Al-doped LiB3O5 crystal are quite suitable for use in high dose measurements in medical or industrial areas. The trap parameters namely the order of kinetics (b), activation energy (E) and frequency factor (s) associated with the glow peaks of some TL samples were also obtained by computer glow curve deconvolution (CGCD) method.Keywords: Thermoluminescence, Dosimetry, Alkaline earth borates