Synthesis And Properties Of The Silicate Phosphors For Whitle LED

White-light-emitting diodes （W-LEDs） as the new-generation light source havelarge market and great potential for lighting applications. By adopting ultraviolet （UV）/near ultraviolet （NUV） to excite tricolor phosphor to gain white light is the hotspot inthe research field recently, and also considered the leading of the new-generation lightsource. In the paper, we investigate the phosphors used by W-LEDs excited by UV orNUV, adulterate rare earth ions in the silicates and synthesize the tricolor phosphorand investigate their luminescent properties、color coordinate and transfer mechanismbetween rare earths,and so on. The main results obtained are as follows:1. Novel red phosphors Li₂SrSiO₄:Sm³⁺, Eu³⁺have been synthesized. The luminescentproperties of the phosphors Li₂SrSiO₄:Sm³⁺, Li₂SrSiO₄:Sm³⁺ and Li₂SrSiO₄:Sm³⁺, Eu³⁺have been investigated under NUV excitation. Under the excitation of405nm, thephosphor Li₂SrSiO₄:Sm³⁺, Sm³⁺ emits stronger red light, when the optimumconcentration of Eu³⁺/Sm³⁺ is4/1, the chromaticity coordinate is （0.640,0.330）,which is very close to the the NTSC standard values （0.670,0.330）, it is a promisingred emitting material possibly.2. Color-tunable phosphors Sr₃MgSi₂O₈:Ce³⁺, Tb³⁺have been synthesized. Theluminescent properties were investigated under UV excitation, we focus theinvestigation keystone on the variety of the emission intensity of the rare earth ionswith the doped concentration, and the energy transfer between Ce³⁺and Tb³⁺. Theresults indicate that with the increasing of Tb³⁺ions, the color of Sr₃MgSi₂O₈:Ce³⁺,Tb³⁺moves from blue region to green region.3. Sr₃MgSi₂O₈:Ce³⁺, Dy³⁺as a single matrix white phosphor has been synthesized.By codoping Ce³⁺ions and Dy³⁺ions to create a single phase of white-emittingphosphor, we used the high temperature solid phase method to synthesizeSr₃MgSi₂O₈:Ce³⁺, Dy³⁺phosphors, and discussed the energy transfer and luminescent properties of a series of samples under UV excitation.