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

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.