Luminescence Properties of Eu[sup 2+]-Doped MAl[sub 2−x]Si[sub x]O[sub 4−x]N[sub x] (M=Ca, Sr, Ba) Conversion Phosphor for White LED Applications

Undoped and Eu-doped were synthesized by a solid-state reaction method at under nitrogen–hydrogen atmosphere. The solubility of in was determined. Nitrogen can be incorporated into by replacement of by , whose amount of solubility depends on the M cation. The solubility of is very low in and lattices ( and 0.045, respectively), whereas a large amount of can be incorporated into . Incorporation of hardly modifies the luminescence properties of -doped because of limited solubility of , showing the blue and green emission at almost constant wavelength of 440 and , respectively. -doped exhibits a broad green emission band with a maximum in the range of , depending on the concentration of and . In addition, both excitation and emission bands of show a significant red shift as nitrogen is incorporated. can be efficiently excited in the range of radiation, which makes this material attractive as conversion phosphor for white light-emitting diode (LED) lighting applications.