Improvement of SrAl2O4:Eu2+, Dy3+ Phosphor via AlN Incorporation

SrAl2O4:Eu2+,Dy3+ long-lasting phosphors were incorporated AlN successfully by a conventional solid-state reaction in the reductive atmosphere. When a certain amount of AlN was doped, the specimen SrAl2O4-3xN2x: Eu2+, 0.01Dy3+ (x = 0.0-0.2) maintained the phase purity. Under the excitation at 398nm, an intense broadband emission centered at 514 nm, originating from the 4f65d1→4f7 transition of Eu2+, was observed. It is noteworthy that partial nitridation leads to an enhancement in the emission intensity up to 240%. The study of thermal stability shows that the intensity of SrAl2O3.55N0.3:Eu2+,0.01Dy3+ phosphor still remains 72% at 150 °C comparing with the initial, while only 62% for the un-doped phosphor. Taking enhanced photoluminescence (PL) property and good thermal stability into account, SrAl2O4-3xN2x:Eu2+, 0.01Dy3+ is a promising candidate for the phosphors used in alternating current (AC) LEDs.