Synthesis and luminescence properties of YF ₃=Ce ³⁺/Tb ³⁺ nanocrystals

YF ₃:Ce ³⁺, YF ₃:Tb ³⁺, and YF ₃:Ce ³⁺/Tb ³⁺ nanocrystals were synthesized by an ethylenediaminetetraacetic acid (EDTA)-assisted hydrothermal method and characterized by X-ray diffraction and scanning electron microscope. In the excitation spectra, there is one broad excitation band at 285 nm for YF ₃:Ce ³⁺ and 255 nm for YF ₃:Tb ³⁺, which are related to the f-d excitations of the Ce ³⁺ and Tb ³⁺ in the host, respectively. In the emission spectra of YF ₃:Ce ³⁺/Tb ³⁺ nanocrystals under different excitation wavelengths (285 and 255 nm), both spectra exhibit the emissions of Ce ³⁺ and Tb ³⁺, indicating that energy transfer could take place not only from Ce ³⁺ to Tb ³⁺ but also from Tb ³⁺ to Ce ³⁺ ions.