The synthesis and luminescent properties of novel water-soluble CaF2:Tb3+ nanoparticles.

Novel water-soluble CaF 2 :Tb 3+ nanoparticles were synthesized using benzoimidazole-5-carboxylic acid (Ligand) as surfactant. The particle size of the nanoparticles is below 10 nm. The investigation of fluorescence properties showed that there exists energy transfer from the surface coating of nanoparticles to Tb 3+ leading to the sensitized fluorescence emission of Tb 3+ . The luminescence lifetimes of Tb 3+ were 937.56 μs (37.41%) and 2.78 ms (62.59%). It is more important that Cu 2+ and Fe 3+ can give rise to emission quenching to the Tb 3+ of nanoparticles, especially Cu 2+ . In the region of 2.5×10 −5 –5×10 −4 M, the higher the concentration of Cu 2+ or Fe 3+ is, the stronger fluorescence quenching to the Tb 3+ is. Additionally, the possible mechanisms of the luminescence quenching were also discussed. [ABSTRACT FROM AUTHOR]