Synthesis and photoluminescence properties of NaLaMgWO6:RE3+ (RE = Eu, Sm, Tb) phosphor for white LED application

Single phase of NaLa1−xMgWO6:xRE3+ (0 < x ≤1) (RE = Eu, Sm, Tb) phosphors were prepared by solid-state reaction method. X-ray diffraction, scanning electron microscopy, the morphology energy-dispersive X-ray spectroscopy, UV–vis diffuse reflectance spectra and photoluminescence were used to characterize the samples. Under the light excitation, NaLaMgWO6:Eu3+, NaLaMgWO6:Sm3+ and NaLaMgWO6:Tb3+, phosphors showed the characteristic emissions of Eu3+ (5D0 → 7F4, 3, 2, 1), Sm3+ (4G5/2 → 6H5/2, 7/2, 9/2), and Tb3+ (5D4 → 7F6, 5, 4, 3), respectively. The intensity of the red emission for Na(La0.6Eu0.4)MgWO6 is 2.5 times higher than that of (Y0.95Eu0.05)2O3 under blue light irradiation. The quantum efficiencies of the entitled phosphors excited under 394 nm and 464 nm are also investigated and compared with commercial phosphors Y2O3:Eu3+, Sr2Si5N8:Eu2+ and Y3A5G12:Ce3+. The results demonstrated NaLaMgWO6:RE3+ phosphors as potential candidates for white light emitting diode pumped by UV or blue chip.