Crystal structure and luminescence property of a novel single-phase white light emission phosphor KCaBi(PO4)2:Dy3+

Abstract

A novel white light emitting phosphor KCaBi(PO4)2:Dy3+ for UV excitations has been synthesized by the solid state reaction technique. The powder X-ray diffraction patterns, Rietveld refinement and XPS were utilized to confirm the phase composite and crystal structure. The excitation and emission spectra, decay curves and chromaticity coordinates of the as-prepared phosphors were characterized to investigate the photoluminescence properties for application in white light-emitting diodes. The results revealed that the KCaBi(PO4)2:Dy3+ phosphors can be effectively assimilated with near ultraviolet, and exhibit two emission bands peaked at 480nm(blue light) and 580nm(yellow light) originating from the 4F9/2-6H15/2, 4F9/2-6H13/2 transitions of Dy3+, respectively. The critical distance was calculated to be about 17.96Å and the concentration quenching mechanism was verified as dipole-dipole interaction. Additional, the optimal chromaticity coordinates were determined to be (0.3118, 0.3309) and a better thermal stability of the phosphors have been illustrated.