Preparation, structure and luminescence properties of deep red phosphors SrSiN2:Eu2+

Abstract This paper reported a novel synthetic route to Eu 2+ doped SrSiN 2 deep red phosphors for white light-emitting diodes. A series of single-phased and high-efficiency SrSiN 2 :Eu 2+ red phosphors were synthesized based on this method. Their structure, morphology, luminescence, quantum efficiency (QE) and thermal quenching properties were investigated and compared with those of SrSiN 2 : Eu 2+ prepared by the conventional route. It was found that the addition of a small amount of Si 3 N 4 could promote the formation of SrSiN 2 from Sr 2 Si 5 N 8 phase. A highly uniform rod-shaped morphology was obtained based on this method. The X-ray powder diffraction and the Rietveld refinement analysis identified the preferential crystalline orientation growth. Under the blue light excitation, Eu 2+ doped SrSiN 2 phosphors showed excellent optical properties. Compared with those prepared by the conventional approaches, the external QE of SrSiN 2 :Eu 2+ phosphor was greatly improved, allowing it a promising phosphor for white LEDs.