Luminescence properties of Eu2+-doped Ba3Si6O12N2 green phosphor: concentration quenching and thermal stability

The efficient Eu2+-doped Ba3Si6O12N2 green phosphors were prepared by a traditional solid state reaction method under N-2/H-2 atmosphere at a temperature up to 1350 degrees C for 12 h. Photoluminescence (PL) properties showed a broad emission band with a peak of 525 nm and the full width of half-emission maximums (FWHM) of 70 nm under 460 nm light irradiation. The X-ray diffraction patterns (XRD) and scanning electron microscope (SEM) images of the synthesized powder demonstrated its pure phase and excellent crystallization. Quenching concentration in this phosphor was found to be 0.3. The mechanisms of concentration quenching and redshift of emission peak with increasing concentration of Eu2+ were studied. The temperature dependence measurement of this green phosphor revealed excellent thermal quenching property compared to silicate green phosphor. It is believed that Ba3Si6O12N2:Eu2+ is an excellent green phosphor for UV or blue chip based white LEDs.