| Silicate matrix has good chemical stability and thermal stability. People have focused a lot of attention on the research and development of silicate phosphor matrix for a long time. Due to the high lumens efficiency, good color reproduction characteristics of single matrix white phosphor, the research on it has great significance.In this paper, series samples of white LED phosphor M2SiO4:Dy3+, Eu3+(M= Mg, Ca) have been synthesized by high temperature solid state, and the corresponding structure characteristics and near-UV excited luminescent properties of the samples were studied.The X-ray powder diffraction data of series samples M2SiO4: Dy3+,Eu3+(M= Mg, Ca) have good agreement with JCPDS standard card, which shows that the synthetic material is alkaline earth metal silicate, belonged to silicate system.The excitation spectra of Ca2SiO4:Dy3+ show strong absorption near 325nm,350nm, 365nm and 386nm due to H15/2â†'6P3/2,6H15/2â†'6P7/2,6H15/2â†'6P5/2,6H15/2â†'4M21/2 transition of Dy3+. The emission light is at about 480nm,492nm,575nm under 386nm UV excitation. The emission at 482nm and 492nm (Blue) attribute to the 4F9/2â†'6H15/2 transition and 579nm (Yellow) attributes to the 4F9/2â†'6H13/2 transition.Series samples of co-doped Dy3+, Eu3+ M2SiO4 (M=Mg, Ca) have been synthesized. The spectra show that in addition to Dy3+ emission bands in blue and yellow of the characteristic peak, there are four other peaks at orange area 590nm, red area 616nm,653nm,704nm due to the Eu3+ in the 5D0â†'7FJ(J=1,2,3,4). Red light district of emission has been enhanced. The doped rare earth ions Eu3+ luminescence of samples has great impact in color coordinates (CIE) and color temperature.Still we prepared (MgxCa1-x)2SiO4: Dy3+,Eu3+ phosphors and analyzed under UV excitation. Different ratios of alkaline earth ions in the sample affect the spectrum and the color coordinates (CIE).There are 23 figures,8 tables and 45 references in this paper. |
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