Effect of fluxes on synthesis and luminescence properties of BaSi2O2N2:Eu2+ oxynitride phosphors

Eu2+ activated BaSi2O2N2 oxynitride bluish-green phosphor was synthesized adopting conventional high-temperature solid-state reaction method, in which BaF2, Na2CO3 and NH4Cl were used as the fluxes. The phase formation, size distribution and microscopic morphology were characterized to investigate the influence of adding fluxes on photoluminescence properties. The results indicate that with the addition of BaF2 flux, the particle morphology becomes regular and size distribution narrows and the phase purity of BaSi2O2N2:Eu2+ phosphor can be improved effectively. The photoluminescence intensity of BaSi2O2N2:Eu2+ phosphor with BaF2 as flux gets enhanced obviously, which is much higher than that of Na2CO3, NH4Cl and without flux. The optimum content of BaF2 flux is 4 wt%, and the maximum photoluminescence intensity of the BaSi2O2N2:Eu2+ phosphor prepared with BaF2 flux rises to 141%, meanwhile, the phosphors with BaF2 flux exhibits low thermal quenching. The results indicate that the BaSi2O2N2:Eu2+ is sort of promising bluish-green phosphor for application in full-spectra LED.