Ionic Liquid-Based Approach to Monodisperse Luminescent LaF3:Ce,Tb Nanodiskettes: Synthesis, Structural and Photoluminescent Properties

In this paper, a novel and easy synthesis of highly luminescent, water-soluble LaF3:Ce,Tb nanodiskettes (25 nm in diameter) by ionic liquid-based hydrothermal process is reported. X-ray diffraction (XRD), transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM) were used to characterize the structural properties of the LaF3,:Ce,Tb nanodiskettes. Ionic liquid [bmim]BF4 acts as both a co-solvent and a reactant during the synthesis. The effects of EDTA-2Na on the formation of green LaF3:Ce,Tb nanodiskette phosphors were studied and discussed. The luminescent properties of LaF3:Ce,Tb nanodiskettes have been investigated under 254 nm excitation both in solid state and dispersed in solution. The quantum efficiency (in solid state) is about 20% compared with commercial green phosphor. The photoluminescent properties show that the as-prepared La0.8Ce0.15Tb0.05F3 nanodiskettes may be applied as phosphors for high-resolution displays and fluorescent labels for biomolecules.