Ce3+→Eu2+ energy transfer studies on BaMgSiO4 -: A green phosphor for three band white LEDs

Ce3+ luminescence is studied for the first time in BaMgSiO4. Intense and broad blue emission is observed with maximum at 430 nm when excited with 356 nm. Studies on Ba1-2yCeyLiyMgSiO4 (y=0.0025-0.125) show that the emission intensity is maximum for y=0.1 and a decrease in emission intensity is observed for higher y values. The concentration of Eu2+ and Ce3+ are varied in BaMgSiO4:0.1Ce(3+), Eu2+, and BaMgSiO4:0.01Eu(2+), Ce3+ systems, respectively, in order to find the critical concentration of Eu2+ and Ce3+ to achieve high emission intensity of Eu2+. Ba0.75Eu0.05Ce0.1Li0.1MgSiO4 and Ba0.97Eu0.01Ce0.01Li0.01MgSiO4 compositions show maximum Eu2+ emission, and the emission intensity is found to be comparable with that of commercial ZnS:Cu,Al (green phosphor, SONY) under near-UV excitation (400 nm). Commission Internationale de I'Eclairage (CIE) chromaticity coordinates indicate that the Eu2+ and Ce3+ substituted compositions are potential green phosphors for solid-state lighting, light-emitting diode technology. (c) 2007 The Electrochemical Society.