Luminescent properties of Dy3+ or/and Tm3+ co-doped in La3PO7 for white LEDs

Abstract Dy3+/Tm3+ single doped and co-doped La3PO7 phosphors were synthesized by solid state reaction method. The single doped Dy3+/Tm3+ ions showed their characteristic emissions yellow and blue. The luminescence intensity of this phosphor firstly increased and then decreased with increasing concentration of Dy3+ ions. The experimental results and the theoretical calculation indicate that the concentration quenching mechanism of Dy3+ ions in La3PO7 is the dipole–dipole interaction. By changing the doping concentration of Dy3+ and Tm3+ in La3PO7, their corresponding color coordinates are very close to the white color chromaticity coordinates (x = 0.33, y = 0.33). These results indicate that the La3−x−yPO7:xDy3+−yTm3+ phosphors exhibit great potential for use as single-component phosphors for w-LEDs.