High Efficiency Mn4+Doped Sr2MgAl22O36Red Emitting Phosphor for White LED

A novel high efficiency red emitting Sr 2 MgAl 22 O 36 :Mn 4+ phosphor is synthesized by solid-state reaction method. The optimized red emitting Sr 2 MgAl 22 O 36 :Mn 4+ 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 Sr 2 MgAl 22 O 36 :Mn 4+ 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 2 MgAl 22 O 36 :Mn 4+ and (Sr, Ba) 2 SiO 4 :Eu 2+ (green emitting phosphor) excited with a 397 nm near UV-chip.