Synthesis and characterization of lithium tetraborate and lithium triborate phosphors doped with metals and their thermoluminescence properties

Çelik, Muzaffer Gençay
The phenomenon of thermoluminescence (TL) has been interested in the measurement of radiation dose over the past few decades. Thermoluminescence property of a material can be used in surface acoustic wave apparatus, sensor sector and non-linear optics (LASER). Moreover, in dosimetry TL concept has been utilized. Thermoluminescence dosimetry is interested in the fields of environmental, personnel, and clinical radiation applications. In this thesis, dosimetric phosphors lithium tetraborate (Li2B4O7: LTB) [1] and lithium triborate (LiB3O5: LBO) [2] which have been synthesized and doped with metals (Cu, Mn, Ag, Al, In, Eu) and thermoluminescence characteristics of synthesized lithium tetraborate (LTB) and lithium triborate (LBO) were analyzed. Un-doped and doped LTB samples were prepared with solution-assisted method (SAM) and microwave-assisted method (MAM). Synthesized LTB and LBO phosphors were characterized with X-ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FT-IR), Transmission Electron Microscopy (TEM), Scanning Electron Microscopy (SEM), and Differential Thermal Analysis (DTA) to determine structural and morphological properties. Thermoluminescence (TL) properties of the LTB and LBO samples doped with various doping systems such as single dopant, double-dopant, and three dopant systems were studied. TL results demonstrated that 0.08% Cu and 0.04% Ag doped LTB synthesized with SAM has the highest dosimetric sensitivity among the LTB samples produced with SAM and MAM. According to TL results of LBO samples, 1% Al doped LBO sample gave the best TL properties in terms of peak shape and intensity among the synthesized LBO samples.