X-ray luminescence of LaF3: Tb3+ and LaF3: Ce3+, Tb3+ water-soluble nanoparticles

We report x-ray luminescence from LaF3:Ce3+, Tb3+ and LaF3: Tb3+ water-soluble nanoparticles. The x- ray luminescence is dominated by emission from Tb3+ ions, similar to photoluminescence spectra of the nanoparticle aqueous solutions and spectra from nanoparticle powders precipitated from the aqueous samples. Coating the nanoparticles with an insulating inorganic LaF3 or organic H2N-(CH2)(10)-COOH layer can enhance the x- ray luminescence from the aqueous nanoparticles. This enhancement is most likely due to the decreased energy loss due to the particle-solvent interactions. (C) 2008 American Institute of Physics.