Adv. Mater. 2018, 30, 1802489. https://doi.org/10.1002/adma.201802489

The discovery of high efficiency narrow-band green-emitting phosphors is a major challenge in backlighting light-emitting diodes (LEDs). Benefitting from highly condensed and rigid framework structure of UCr4C4-type compounds, a next-generation narrow green emitter, RbLi(Li3SiO4)2:Eu2+ (RLSO:Eu2+), has emerged in the oxide-based family with superior luminescence properties. RLSO:Eu2+ phosphor can be efficiently excited by GaN-based blue LEDs, and shows green emission at 530 nm with a narrow full width at half maximum of 42 nm, and very low thermal quenching (103%@150 °C of the integrated emission intensity at 20 °C), however its chemical stability needs to be improved later. The white LED backlight using optimized RLSO:8%Eu2+ phosphor demon-strates a high luminous efficacy of 97.28 lm W−1 and a wide color gamut (107% National Television System Committee standard (NTSC) in Commission Internationale de L’Eclairage (CIE) 1931 color space), suggesting its great poten-tial for industrial applications as liquid crystal display (LCD) backlighting.