Self-propagating high temperature synthesis of yellow-emitting Ba2Si5N8:Eu2+ phosphors for white light-emitting diodes

Abstract

High-performance nitride phosphors, Ba2Si5N8:Eu2+, were prepared by the self-propagating high temperature synthesis method. The broadband absorption in the range of 380–500nm indicated that the resultant phosphors were effectively excited by an InGaN blue light-emitting diode (400∕470nm). The emission peak position of Ba2−xEuxSi5N8 (x=0–0.3) varied from 572to650nm with increasing Eu2+ concentration, and the intensity was maximized at x=0.04. The optimized sample gave a strong yellow emission peak at 580nm. The redshifting behavior of the emission band was attributed to three factors: energy migration, crystal field strengthening, and reabsorption.