Luminescence properties of Ca1-xSrx(Ga1-yAly)(2)S-4 : Eu2+ and their potential application for white LEDs

A series of Ca1-xSrx(Ga1-yAly)(2)S-4:0.10Eu(2+) (0.0 <= x <= 1.0, y=1.0; 0.0 <= y <= 1.0, x=0) phosphors was synthesized by the evacuated sealed quartz ampoule method. X-ray powder diffraction analysis confirmed the formation of the complete solid solutions of Ca1-xSrxAl2S4:0.10Eu(2+) and Ca(Ga1-yAly)(2)S-4:0.10Eu(2+). With the Sr(x) and Al(y) content increasing, the emission peaks of Ca1-xSrxAl2S4:Eu2+ and Ca(Ga1-yAly)(2)S-4:Eu2+ show an obvious blueshift in the range of 496-556 nm. A tunable bluish-green to greenish-yellow light can be controlled by simply adjusting the content of Sr(x) in Ca1-xSrxAl2S4:Eu2+ and Al(y) in Ca(Ga1-yAly)(2)S-4:Eu2+. All the characteristics indicate that the Ca1-xSrx(Ga1-yAly)(2)S-4:Eu2+ solid solution phosphors are good phosphor candidates for white light-emitting diodes (LEDs). (C) 2008 The Electrochemical Society.