Thermal degradation of BaAl_2Si_2O_8:Eu^(2+) phosphor excited by near ultraviolet light

Eu2+ doped BaAl2Si2O8 phosphor was synthesized by one-step calcination of precursors that were prepared by chemical co-precipitation.The thermal degradation properties of BaAl2Si2O8:Eu2+ were investigated by photoluminescence,lifetime and chromaticity coordinate measurements.BaAl2Si2O8:Eu2+ is efficiently excited by incident light of 250-400 nm,which matches the emission of near ultraviolet LED chips well.BaAl2Si2O8:Eu2+ exhibits broad blue emission at 470 nm because of the 4f65d1-4f7(8S7/2) transition of Eu2+ ions,and the emission band shows an unusual blue shift with bandwidth broadening and emission intensity decreasing as the annealing temperature is increased.The luminescence decay and CIE chromaticity coordinates of BaAl2Si2O8:Eu2+ were determined to investigate its application in white LEDs.

Eu2＋doped BaAl2Si2O8 phosphor was synthesized by one-step calcination of precursors that were prepared by chemical co-pre- cipitation. The thermal degradation properties of BaA12Si2O8：Eu2＋ were investigated by photoluminescence, lifetime and chromaticity coordinate measurements. BaA12Si208：Eu2＋ is efficiently excited by incident light of 250--400 nm, which matches the emission of near ultraviolet LED chips well. BaAl2Si2Os：Eu2＋ exhibits broad blue emission at 470 nm because of the 4f65d1-4f7 （8S7/2） transition of Eu2＋ ions, and the emission band shows an unusual blue shift with bandwidth broadening and emission intensity decreasing as the annealing temperature is increased. The luminescence decay and CIE chromaticity coordinates of BaAl2Si2O8：Eu2＋ were determined to investigate its application in white LEDs.