High Efficiency Mn 4+ Doped Sr 2 MgAl 22 O 36 Red Emitting Phosphor for White LED

Abstract

A novel high efficiency red emitting Sr2MgAl22O 36:Mn4+ phosphor is synthesized by solid-state reaction method. The optimized red emitting Sr2MgAl22O 36:Mn4+ phosphor exhibits high quantum efficiency (QE) of ̃80%, fluorescence lifetime of ̃1.25 ms and the Commission International de I'Eclairage (CIE) chromaticity coordinates (0.72, 0.27). The Sr2MgAl22O36:Mn4+ phosphor shows excitation bands at ̃400 and 470 nm which matches well with working wavelength of existed LED chips can be used as excitation source to generate white emission. White LED was fabricated by using mixed phosphors Sr 2MgAl22O36:Mn4+ and (Sr, Ba) 2SiO4:Eu2+ (green emitting phosphor) excited with a 397 nm near UV-chip. © 2012 The Electrochemical Society.