Luminescent properties of β-SiAION:Eu2+ green phosphors synthesized by gas pressured sintering

Abstract

β-SiAION: Eu2+ oxynitride green phosphors with compositions of EuxSi6-zAlzOzN8-z (x=0.0065 -0.0390, z = 0.231) were successfully prepared using GPS (gas pressured sintering) method. The phase purity, microstructure, luminescent and thermal quenching properties for the prepared β-SiAION:Eu2+ phosphors were investigated in detail. The prepared β-SiAION:Eu 2+ phosphor samples with Eu2+ doping concentration of x < 0.0238 showed pure single β-SiAION phase. The prepared β-SiAION: Eu2+ phosphors absorbed UV-visible spectral region, and showed a single intense broadband emission in a range from 525 to 540 nm. The effects of the Eu2+ doping concentration on the optical properties for the β-SiAION: Eu2+ phosphors were discussed under consideration of concentration quenching. The temperature dependence of photoluminescence (PL) properties was investigated from 25 to 300°C, and the activation energies (ΔE) for thermal quenching of the prepared β-SiAION:Eu2+ phosphors were determined by Arrhenius fitting. The experimental results clearly indicates that the prepared β-SiAION:Eu2+ has great potentials as a down-conversion green phosphor for white light emitting diodes (LEDs) utilizing near UV or blue LEDs as the primary light source. © 2008 The Ceramic Society of Japan. All rights reserved.