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In recent years, has been developed for many types of LED new red phosphor, such as tungsten / molybdate, aluminates, silicates, etc., wherein the tungsten / molybdate as an optical material, having a good light-emitting properties, stability and application of tungsten molybdate system in the ultraviolet region can effectively stimulate and emitting higher brightness, the excitation spectrum has a broad charge transfer band in the near-UV excitation doped Eu3 strong red In this paper, the high temperature solid phase was prepared the red phosphor Y1.97 xLixW0.96Mo0.04O6-δ: of Eu3, and Y1.97-xLixMoO6-δ: Eu3 by x-ray diffraction (XRD), scanning electron microscopy, fluorescence spectrometer for material Characterization and luminescence properties of doped with a small amount of Mo6 ion Y2WO6: Eu3 due the Mo6 and W6 ionic radius is relatively similar, so when the Mo6 ion incorporated into the matrix, the matrix structure has not changed significantly in the excited spectrum when doped with Mo6 charge transfer band edge widened from 370 nm to 430nm. and the emergence of the two absorption peaks at 275 nm and 365nm at sharp peak belongs to Eu3 peaks. the emission spectrum of the sample is composed of several groups of sharp peaks, are Eu3 peaks, respectively, 581nm, 591 nm, 611nm belongs Eu3 the 5D0 → 7FJ (J = 0,1,2,3) transitions .5 D0 → 5D0 → 7F1 transition of emission intensity at 7F2 transition described the Eu3 ion occupies the non-inversion symmetry position, the emission intensity is also increased with the increase of the concentration of Li ions, when the concentration of Li is 0.25, the strongest intensity. wide peak is the Mo-O charge transfer transition Y1.97-xLixMoO6-δ: Eu3 excitation spectrum in the range 240-445nm at the absorption peak at 365nm at within the range of 580nm-700nm, with a few emission peaks, are all characteristic of Eu3 ion emission, which peak in the emission intensity of the emission peak at 612nm (5D0 → 7F2 transition) at most, while the other groups peak intensity is very weak, peaking at 586nm (5D0 → 7F1 transition), 593 nm (of 5D0 → 7F1 transition) at the emission intensity at .5 D0 → 7F2 transition is stronger than the 5D0 → 7F1 Eu3 ions occupy the position of non-inversion symmetry. doping Li, luminous intensity, because followed by a scanning electron microscope observation, when the two compounds after doping Li particle becomes large in size, to form a hexagonal shape, and press the growth of a certain direction, improving the degree of crystallinity of the phosphor, as well as lower the melting point of the Li, can play a lubricating the role of the agent to Eu3 easily enter the matrix lattice.
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