| Rare-earth ions-doped silicate phosphors were studied extensively for White light emitting diodes (LEDs), because they have the advantages of good luminescent properties.Eu2+, Ce3+, Tb3+ and Mn2+ ions-doped Sr2MgSiO5 phosphors were prepared via high-temperature solid state reaction method and sol-gel process. Luminescent mechanism and characteristics of all samples were studied.Eu2+ ion-doped Sr2MgSiO5 phosphor was prepared. The lattice structures of the samples were analyzed by Powder X-ray diffraction (XRD) and Fourier Transform Iinfrared Spectroscopy (FTIR). Morphologies of the samples were observed by scanning electron microscopy (SEM). The results showed that lattice structure of Eu2+ ion-doped Sr2MgSiO5 samples was pyramidal system. The influence of flux on luminescence properties of Eu2+ ion-doped Sr2MgSiO5 phosphor was studied. The results of spectral analysis showed that flux changed the emission intensity of Sr2MgSiO5:Eu2+ samples at different wavelengths.Emission wavelength and relative intensity of the samples changed.In order to study the luminescence properties and energy transfer between Eu2+ and Mn2+, Eu2+ ions and Mn2+ ions co-doped samples were prepared. The results showed that excitation bands of the samples ranged from 250nm to 450nm. When excited at 365nm, the emission spectrum of the samples consists of three bands:blue, green and red, respectively. When Eu2+ ions and Mn2+ ions co-doped, the energy of Eu2+ ions was transferred to Mn2+ ions, which made Mn2+ ions became luminescence center in Sr2MgSiO5 host.In order to further study the energy transfer between Ce3+ and Tb3+ in Sr2MgSiO5 host. Ce3+ ions and Tb3+ ions co-doped samples were prepared. The results of spectral analysis showed that Ce3+ ions sensitized Tb3+ ions efficiently when excited at 350nm in Sr2MgSiO5 host. The energy of Ce3+ ions was transferred to Tb3+ ions, which led to the characteristic emission of Ce3+ ions decreased and the characteristic emission of Tb3+ ions enhanced.
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