Eu 2+ -activated MgAl 2 Si 4 O 6 N 4 : a novel oxonitridoalumosilicate blue phosphor for white LEDs.

Recently, blue-emitting phosphors have attracted great interest due to their application in full-spectrum white light illumination. In this paper, a novel blue-emitting MgAl 2 Si 4 O 6 N 4 :Eu 2+ phosphor was successfully synthesized through the solid-state reaction method in a reducing atmosphere. Under the excitation of near-ultraviolet (n-UV) light, the MgAl 2 Si 4 O 6 N 4 :0.02Eu 2+ phosphor effectively emits a broad blue emission band centered at 456 nm with the FWHM as large as 81 nm. With the increasing Eu 2+ concentration, the emission bands of MgAl 2 Si 4 O 6 N 4 :Eu 2+ shift to a shorter wavelength and the FWHMs broaden gradually. Moreover, the MgAl 2 Si 4 O 6 N 4 :0.02Eu 2+ phosphor exhibits a slight thermal quenching at a higher temperature. After fabricating the as-prepared MgAl 2 Si 4 O 6 N 4 :0.02Eu 2+ phosphor into a white LED device, the intense neutral white light emission is obtained with excellent CRI (87.4) and CCT (5645 K). These results suggest that the blue MgAl 2 Si 4 O 6 N 4 :Eu 2+ phosphor is a promising candidate in n-UV excited white LEDs.