Modulation of Lattice Strain‐Induced Eu ²⁺ Single Lattice Site Emission for Narrow‐Band Green Phosphors in High‐Performance Laser Displays

ABSTRACT In this study, a strategy of modulating lattice strain is adopted to eliminate the cyan emission peak of UCr 4 C 4 ‐type phosphors with double‐peak emission. A narrow‐band green phosphor with single‐peak emission is obtained: Rb 0.5 K 2.5 Na(Li 3 SiO 4 ) 4 (RKNLSO or Rb 0.5 K 2.5 Na): Eu 2+ . Through local structure analysis, formation energy calculation, and EPR spectrum analysis, the lattice migration of Eu 2+ is confirmed. RKNLSO: 0.09Eu 2+ exhibits an excitation wavelength range of 300 to 500 nm, with a peak emission at 532 nm and a full width at half maximum (FWHM) of 45 nm. Its external quantum efficiency reaches 42.7%. The integrated emission intensity at 150°C reaches 93% of that at room temperature. The RKNLSO: 0.09Eu 2+ under blue laser excitation gradually saturated at 88.75 W/mm 2 , at which point the luminous flux reached 2351.77 lm. A WLED prepared with RKNLSO: 0.09Eu 2+ as the green component has a 110% NTSC color gamut. Projection devices use this WLED as a light source to demonstrate vibrant display colors, indicating that RKNLSO: 0.09Eu 2+ has significant potential as a green component for display applications. In addition, the strategy of targeted activation of lattice sites through lattice strain modulation provides High‐pressure, Laser display, Narrow‐band phosphor, Photoluminescence, and Wide colour gamuta new approach to developing highly efficient phosphors.