Narrow Bandwidth Luminescence in Sr2Li(Al,Ga)O4:Eu2+ by Selective Site Occupancy Engineering for High Definition Displays

Abstract It remains a critical challenge to develop narrow‐band emitters for wide color gamut displays. Herein, it is designed by the selective site occupancy engineering and an unprecedented narrow‐band green‐emitting phosphor is prepared through chemical substitution. By introducing Ga 3+ ions into Sr 2 LiAlO 4 :Eu 2+ phosphor, the distribution of Eu 2+ ions in Sr1 and Sr2 sites is effectively controlled, and only one type of luminescent centers Eu 2+ (Sr1) is remained in Sr 2 LiAl 0.6 Ga 0.4 O 4 :Eu 2+ due to the compression effect of Sr2O 8 polyhedra. Sr 2 LiAl 0.6 Ga 0.4 O 4 :Eu 2+ phosphor presents an extremely narrow‐band green emission centered at 512 nm with a full‐width at half‐maximum of only 40 nm. The wide color gamut (107% National Television System Committee) of the as‐fabricated white liquid crystal displays and the vivid figures captured from the projector demonstrate the potential application of narrow‐band emitter for wide‐color gamut displays. This work provides the design principles of realizing narrow‐band emission by selective site occupancy engineering and can set the stage for the exploring of Eu 2+ ‐activated phosphor for high definition displays.