Investigations of thermally and optically stimulated luminescence properties of CaSO4:Eu using precipitation method

Calcium Sulfate (CaSO4) is a well-known material and also was recognized as a useful TL material in radiation dosimetry. However, except the chemical, structural and thermoluminescence properties, little or no paper has been reported about properties of OSL characteristics especially about the activation energies of CaSO4 phosphors in the literature. For this reason, in this study, the Eu-doped calcium sulfate sample was synthesized using the precipitation method and the sol-gel assisted precipitation (Vol-Vey Method) method to create new traps and recombination centers and the OSL characteristics were investigated for suitability in the radiation dosimetry. The synthesized CaSO4 phosphors were analyzed by XRD and SEM to ensure the product matched with the planned material and to have an idea about the crystallography and microstructure morphology of the material. In addition, FT-IR analysis was performed to observe the vibrational modes of functional groups of the produced phases and DSC and TG Analysis were used for investigation the chemical and physical changes in/on material during temperature measurement. In order to obtain the OSL signals and investigate the dosimetric characteristics of cold pressed Eu doped CaSO4 pellets, all the readouts have been performed with a Riso TL/OSL reader model DA-20 after the materials' exposure to beta source (90Sr/90Y). In addition to examining the dosimetric properties such as dose response, reusability and fading properties, minimum detectable dose, thermal stability and effect of reading temperature were also examined and activation energies were determined. As a result, this study showed to be superior dosimetric properties of CaSO4:Eu pellets and shed light to the literature to use extensively and to evolve with dosimetric purposes of this material in the future.