Luminescence properties and energy transfer of color-tunable LaAl2.03B4O10.54:Tm3+,Dy3+ phosphors

Abstract

LaAl2.03B4O10.54:Tm3+,Dy3+ phosphors were prepared by the sol–gel method. The phase, luminescence properties, energy transfer mechanism and CIE color coordinates of the samples were analyzed by XRD, SEM and fluorescence spectrometry. The results show that the LaAl2.03B4O10.54:Tm3+ phosphor emits blue light at a monitored wavelength of 357 nm and the concentration quenching point of Tm3+ ion is 0.06 mol. In the La0.94-yAl2.03B4O10.54:0.06Tm3+,yDy3+ phosphors, the luminescence intensity of Tm3+ decreases with an increase in the Dy3+ doping concentration, while the luminescence intensity of Dy3+ increases. The color of the emitted light can be adjusted by changing the doping concentration of Dy3+ or changing the wavelength of the excited light. There is energy transfer between the Tm3+ and Dy3+ ions. When the doping concentration of Dy3+ ions is 0.1 mol, the energy transfer efficiency reaches 63.65% and the energy transfer mechanism is an electric dipole-electric dipole interaction. These results clearly indicate that La0.94-yAl2.03B4O10.54:0.06Tm3+,yDy3+ phosphors can be used as color tunable phosphors in the field of WLEDs.