Near UV-based LED fabricated with Ba 5SiO 4(F,Cl) 6:Eu 2+ as blue- and green-emitting phosphor

Abstract

A series of halosilicate phosphor, Ba 5SiO 4(F,Cl) 6:Eu 2+, were synthesized by a solid state reaction. Excited by 370-nm light, Ba 5SiO 4Cl 6:Eu 2+ exhibits a broad emission band peaking at 440 nm. Partial substitution of Cl − with F − in the host lattice leads to red-shift in the emission band with centering wavelength from 440 nm to 503 nm. The possible mechanism for the luminescence change was discussed based on the XRD patterns. Blue and green LEDs were fabricated by combination of a 370 nm-emitting near UV chip and the optimal Ba 5SiO 4Cl 6:Eu 2+ and Ba 5SiO 4(F 3Cl 3):Eu 2+, respectively. This series of phosphors is considered as a promising blue and green component used in fabrication of near UV-based white LEDs.