Synthesis and characterization of Ce³⁺-, Pr³⁺-, Tm³⁺-doped Li₆Lu(BO₃)₃ phosphors for X-ray and neutron imaging

Rare-earth-doped phosphors are drawing attention due to their applications in various fields including medical imaging. Lithium lutetium borate has very good absorption efficiency in comparison to other phosphors. The presence of Lu with its high effective atomic number (Z _eff = 52) and high molecular weight (M.Wt = 393 g/mol) make lithium lutetium borate a potential detector for X-ray imaging. On the other hand, the presence of ⁶Li (lithium) and ¹⁰B (boron) may make Li₆Lu(BO₃)₃ as a promising neutron detector. For this work Li₆Lu(BO₃)₃:Ce³⁺, Li₆Lu(BO₃)₃:Pr³⁺ and Li₆Lu(BO₃)₃:Tm³⁺ were synthesized by using a solid-state reaction method. The crystallinity and the particle morphology of the synthesized phosphors were characterized by XRD (X-ray diffraction) and FE-SEM (field-emission scanning electron microscopy). Luminescence properties such as X-ray-induced luminescence, the proton-induced luminescence and the UV photoluminescence were measured for the synthesized phosphors.