Preparation and luminescence properties of rod-like LaF3:Eu3+ nanocrystals

Rod-like LaF3: Eu3+ nanocrystals were synthesized by a simple liquid method at room temperature, and the properties were characterized. XRD patterns showed that the hexagonal phase LaF3 crystals with a better crystallinity were obtained at room temperature, the diffraction peaks intensities increased with the increase of annealing temperature and no impurity phase was observed. TEM images showed that the LaF3: Eu3+ nanocrystals are in rod shape with the diameter of 8 nm and length to 50 nm. Photoluminescence properties indicated that the strongest emission peak of the obtained rod-like LaF3: Eu3+ nanocrystal is near 589 nm, corresponding to the D-5(0)-F-7(1) transition of Eu3+ Which suggests that Eu3+ is located at C-2 symmetry lattice of La3+ in LaF3 host, in addition, the quenching molar fraction of Eu3+ is 5% and the lifetime increases with the increase of annealing temperature.