Effect of Flux on the Synthesis and Luminescence Properties of BaSi2O2N2:Eu2+ Oxynitride Phosphors

Abstract Eu 2+ activated BaSi 2 O 2 N 2 oxynitride bluish-green phosphor was synthesised adopting conventional high-temperature solid-state reaction method, in which BaF 2 , Na 2 CO 3 and NH 4 Cl were used as the fluxes. The phase formation, size distribution and microscopic morphology were characterised to investigate the influence of adding flux on photoluminescence properties. The results indicate that with the addition of BaF 2 flux, the particle morphology became regular and size distribution narrowed and the phase purity of BaSi 2 O 2 N 2 :Eu 2+ phosphor can be improved effectively. The photoluminescence intensity of BaSi 2 O 2 N 2 :Eu 2+ phosphor with BaF 2 as fluxes gets enhanced obviously, which is much higher than that of Na 2 CO 3 , NH 4 Cl and without flux. The optimum content of BaF 2 flux is 4 wt%, and the maximum photoluminescence intensity of the BaSi 2 O 2 N 2 :Eu 2+ phosphor prepared with BaF 2 flux raise to 141%, meanwhile, the phosphors with BaF 2 flux exhibits low thermal quenching. The results indicate that the BaSi 2 O 2 N 2 :Eu 2+ is sort of promising bluish-green phosphor for application in full-spectra LED.