LAUSR

Abstract A series of Ce-, Dy-, and Eu-doped NaCa4(BO3)3 phosphors for light emitting diodes (LEDs) applications were prepared using a high temperature solid state reaction method. These phosphors are investigated by X-ray diffraction, scanning electron microscopy, photoluminescence spectra, and Commission International de I’Eclairage chromaticity coordinates. It is found that crystals Ca3B2O6 and NaCa4(BO3)3 coexist in the phosphors, which can provide various local environments for the doped rare earth ions and affect the emission behavior of Ce3+. The emission band splitting of Dy3+ is observed for the as-prepared phosphors. The energy transfer from Ce3+ to Dy3+ occurs in the Ce3+/Dy3+ codoped phosphors. For Ce/Dy codoped phosphors, we find that the emission peak of Ce3+ moves to the longer wavelength with increasing the concentration of Ce3+ and Dy3+. However, the emission peak of the Ce3+ single doped phosphor keeps nearly unchanged with the increase of Ce3+ content. The luminescence properties of the phosphors could be tailored effectively by varying the concentrations of the Ce, Dy, and Eu ions as well as the excitation wavelengths. The NaCa4(BO3)3:Ce, Dy, Eu phosphors reported here demonstrate promising applications prospect in LEDs.