Hydrothermal Synthesis and Property of Rare Earth of Fluoride NaYF<sub>4</sub>:Er<sup>3+</sup> Materials

High quality NaYF 4 and NaYF 4 :Er 3+ materials were prepared using EDTA-assisted hydrothermal method. The effects of doping of Er 3+ on the shape of samples were discussed. The samples were characterized by X-ray powder diffraction (XRD), and scanning electron microscopy (SEM). XRD patterns show that the samples are hexagonal phase of NaYF 4 and NaYF 4 :Er 3+ with good crystallization. SEM images present that the samples of NaYF 4 are homogeneous nanorods with a diameter of 342 nm and a length of 1043nm，the NaYF4:Er3+(5%) sample with a diameter of180.7nm and a length of 1220nm, and NaYF 4 :Er 3+ (10%) with a diameter of 139.4nm and a length of 939.9nm.The sizes of the NaYF 4 and NaYF 4 :Er 3+ nanoparticles are basically consistent with that calculated from XRD peak via the Scherrer equation.