Tunable-Color Luminescence via Energy Transfer in NaCa_(13/18)Mg_(5/18)PO_4:A (A = Eu~(2+)/Tb~(3+)/Mn~(2+), Dy~(3+)) Phosphors for Solid State Lighting

摘要

A series of NaCa_(13/18)Mg_(5/18)PO_4(NCMPO):A(A = Eu~(2+)/Tb~(3+)/Mn~(2+), Dy~(3+)) phosphors have been prepared by the high-temperature solid-state reaction method. The Xray diffraction (XRD) and Rietveld refinement, X-ray photoelectron spectroscopy (XPS), photoluminescence (PL), cathodoluminescence (CL), decay lifetimes, and PL quantum yields (QYs) were utilized to characterize the phosphors. The pure crystalline phase of as-prepared samples has been demonstrated via XRD measurement and Rietveld refinements. XPS reveals that the Eu~(2+)/Tb~(3+)/Mn~(2+) can be efficiently doped into the crystal lattice. NCMPO:Eu~(2+)/Tb~(3+)/Mn~(2+) phosphors can be effectively excited under UV radiation, which show tunable color from purple-blue to red including white emission based on energy transfer from Eu~(2+) to Tb~(3+)/Mn~(2+) ions. Under low-voltage electron beam bombardment, the NCMPO:A (A = Eu~(2+)/Tb~(3+)/Mn~(2+), Dy~(3+)) display their, respectively, characteristic emissions with different colors, and the CL spectrum of NCMPO:0.04Tb~(3+) has the comparable intensity to the ZnO:Zn commercial product. In addition, the calculated CIE coordinate of NCMPO:0.04Tb~(3+) (0.252, 0.432) is more saturated than it(0.195, 0.417). These results reveal that NCMPO:A (A = Eu~(2+)/Tb~(3+)/Mn~(2+), Dy~(3+)) may be potential candidate phosphors for WLEDs and FEDs.