The Fabrication And Properties Of Red Phosphors Used For White LED

The fabrication and properties of phosphor used for whit LED were paid more attentionwith the extension of applied field and the development of preparation technology in whiteLED. Especially, the properties of phosphor excited by blue and UV light can effect directlythe color rendering of white LED.A novel stable red phosphor SrMoO₄:Eu³⁺ was prepared by solid state method. Theproperties of this phosphor and the other red phosphor CaMoO₄:Eu³⁺ were improved usingcharge compensation. The influence of the concentration of Eu³⁺, the reaction temperature andthe reaction time on the luminescent properties were studied.It can be seen that the excitation spectra of SrMoO₄:Eu³⁺ included from 200nm to 500nm,which had three excitation peaks at 270nm, 390nm and 470nm;the emission spectra arecomposed of a set of aiguilles included the peaks at 535nm, 590nm, 616nm, 624nm and703nm, which were corresponded with the transition of 5DJ (J=0, 1) -7FJ (J = 1～4) in Eu³⁺.The luminescent intensity were affected when Eu³⁺ entered the crystal lattice andsubstituted the Sr²⁺.The CaMoO₄:Eu³⁺,Na⁺ and SrMoO₄:Eu³⁺,Na⁺ were fabricated by solidstate method using Na⁺ ions for the compensation charges and their intensity were enhancedby 20%.