Eu2+-doped thioaluminates:: New candidates for white LEDs

Three Eu2+-doped thioaluminate phosphors with different light-emitting, colors, green, bluish-green, and blue were synthesized by the evacuated sealed quartz ampoule method. Under UV excitation, CaAl2S4:Eu2+ (CAS), SrAl2S4:Eu2+ (SAS), and BaAl2S4:Eu2+ (BAS) exhibit strong emission bands peaked at 516. 496, and 470 nm, respectively. The fabricated LEDs of CAS, SAS, and BAS show intense green, bluish-green, and blue lighting. They are all believed to be good phosphor candidates for creating white light in phosphor-converted white LEDs.