A highly efficient and thermally stable green phosphor (Lu2SrAl4SiO12:Ce3+) for full-spectrum white LEDs

Abstract

Traditional phosphor-converted white LEDs suffer from the so-called blue-green cavity in their emission spectra. Hence, satisfactory phosphors with sufficient emission around 490 nm are still lacking. Herein, we report a newly designed garnet-type phosphor, Lu₂SrAl₄SiO₁₂:Ce³⁺ (LSAS:Ce³⁺), through chemical unit cosubstitution, whose emission can well fill the blue-green cavity. Importantly, LSAS:Ce³⁺ exhibits nearly zero thermal quenching even at 473 K (200 °C) as well as a high internal quantum efficiency of 93.3%. Finally, the as-fabricated warm white LED device shows a high color rendering index of 97.6 with R9 = 94, indicating its great potential for white LEDs.