Preparation and photoluminescence properties of Y2O3:Eu, Bi phosphors by molten salt synthesis for white light-emitting diodes

Y2O3:Eu, Bi red phosphors were first prepared by molten salt synthesis (MSS) method at a low temperature. X-ray diffraction (XRD), scanning electron microscopy (SEM), and fluorescence spectrophotometer were used to characterize the as-synthesized phosphors. The results show that as-obtained Y2O3:Eu, Bi phosphors have good cubic crystallinity, presenting octahedral morphology with smooth surface and relatively uniform particle size. Bi3+ ion as a sensitizer plays a significant effect on the emission intensity of Y2O3:Eu, Bi by energy transfer from Bi3+ to Eu3+ and the optimal concentration of Bi3+ is 1.5 mol%. Y2O3:Eu, Bi emits excellent red light as the excitation wavelength is between 330 and 420 nm or excited by 254, 466 nm. Meanwhile, its emission intensity is as strong as that of sample prepared by solid-state reaction. So the as-fabricated red phosphors by MSS method would have a promising application in the area of white light-emitting diodes.