Growth and optical properties of Dy3+/Eu3+ co-doped NaYF4 single crystals with cubic lattice for white LED application

Abstract:

Dy3+/Eu3+ co-doped cubic lattice NaYF4 single crystal with high quality in the size of ~Φ1.0 cm×10.0 cm was grown by an improved Bridgman method using potassium fluoride (KF) as assistant flux. X-ray diffraction (XRD), absorption spectra, excitation spectra and emission spectra are measured to investigate the phase and luminescent properties of the crystal. The effects of excitation wavelength and concentrations of Dy3+ and Eu3+ ions on the luminescent characteristics are analyzed. The NaYF4 single crystal with the doping molar concentrations of 1.205% Dy3+ and 0.366% Eu3+ exhibits an excellent white light emission with chromaticity coordinates of x=0.321, y=0.332. It indicates that the Dy3+/Eu3+ co-doped cubic lattice NaYF4 single crystal can be a potential luminescent material for the ultraviolet (UV) light excited white light emitting diode (w-LED).