Green-light-emitting phase in Ba3MgSi2O8:Eu2+, Mn2+ full-color phosphor for white-light-emitting diodes via addition of Si3N4

By adding Si3N4 to the Eu-, Mn-doped Ba3MgSi2O8 upon firing, the formation of a new phase, Ba2SiO4, and its resultant variation of luminescent properties are investigated to compensate the green-light-emission for full-color. Upon addition of Si3N4, a similar to 507-nm peaked band emission of Eu in Ba2SiO4 was induced in coexistence with the concurrent blue-, and red-light-emissions of Eu and Mn in Ba3MgSi2O8. Amount of each phase and as such the transfer of energy in between can be tuned by varying the amount of Si3N4 added, resulting in an interactive change of intensity in between Eu for blue-, green-band-transitions and Mn for red-band-transition in two different phases, due to the indirect contribution of Si3N4 to the formation of Ba2SiO4 and red-shift of photoluminescence. Consequently, white-light with CIE chromaticity coordinate (0.2605, 0.3084) at an optimized amount of Si3N4 has been achieved with this nitride-added adjustable strategy. (C) 2009 Elsevier B.V. All rights reserved.