Hydrothermal synthesis and luminescence behavior of lanthanide-doped GdF/sub 3/ nanoparticles

The lanthanide-doped GdF3nanoparticles have been produced by a simply hydrothermal synthesis procedure. The excitation and emission spectra of the Eu3+-doped GdF3nanoparticles showed that the excitation energy of Gd3+is efficiently transferred to Eu3+in the Eu3+-doped GdF3nanoparticles. Due to very low phonon energies of GdF3matrix, the5D1emission of Eu3+ions in the Eu3+-doped GdF3nanoparticles can be observed at room temperature when the doping concentration of Eu3+ions is lower than 15 mol%. The luminescence intensity of the Eu3+-doped GdF3nanoparticles increased with increasing concentration of Eu3+ions and reached a maximum at approximately 15 mol%. The Er3+-doped GdF3nanoparticles exhibit the typical emission spectra of Er3+in the near-infrared region. The upconversion emission of the Er3+/Yb3+codoped GdF3nanoparticles can also be observed. However, the upconversion emission intensity of the Er3+/Yb3+-codoped GdF3nanoparticles was much weaker than that of the Er3+/Yb3+-codoped GdF3bulk crystal