Enhancing the emission intensity and decreasing the full widths at half maximum of Ba3Si6O12N2:Eu(2+) by Mg(2+) doping.

The promising green oxynitride phosphor, Ba3-xMgxSi6O12N2:Eu(2+) was synthesized by the solid-state reaction method. The effect of Mg(2+) doping on the structure and photoluminescence (PL) properties of Ba3Si6O12N2:Eu(2+) was investigated systematically. The results reveal that the phosphor retains the single phase of Ba3Si6O12N2, with the lattice expanding upon increasing the Mg(2+) concentration, in an appropriate range. This suggests that a large portion of Mg(2+) enters into the interstitial sites of the crystal lattice. At a certain concentration, Mg(2+) doping can greatly enhance the absorption and PL intensity and decrease the full widths at half maximum (FWHM) of Ba3Si6O12N2:Eu(2+) phosphors. The green phosphor Ba2.87Eu0.1Mg0.03Si6O12N2 exhibited a small thermal quenching, which remained 82% of the initial emission intensity when measured at 150 °C. The quantum efficiency measured at 400 nm excitation was 38.5%. All the results indicate that the solid solution Ba3-xMgxSi6O12N2:Eu(2+) can be a good candidate for phosphors applicable in n-UV LEDs for solid-state lighting.