Emerging ultra-narrow-band cyan-emitting phosphor for white LEDs with enhanced color rendition.

ABSTRACT: Phosphor-converted white LEDs rely on combining a blue-emitting InGaN chip with yellow and red-emitting luminescent materials. The discovery of cyan-emitting (470-500?nm) phosphors is a challenge to compensate for the spectral gap and produce full-spectrum white light. Na_0.5K_0.5Li₃SiO₄:Eu²⁺ (NKLSO:Eu²⁺) phosphor was developed with impressive properties, providing cyan emission at 486?nm with a narrow full width at half maximum (FWHM) of only 20.7?nm, and good thermal stability with an integrated emission loss of only 7% at 150?°C. The ultra-narrow-band cyan emission results from the high-symmetry cation sites, leading to almost ideal cubic coordination for UCr₄C₄-type compounds. NKLSO:Eu²⁺ phosphor allows the valley between the blue and yellow emission peaks in the white LED device to be filled, and the color-rendering index can be enhanced from 86 to 95.2, suggesting great applications in full-spectrum white LEDs.

SUBMITTER: Zhao M 

PROVIDER: S-EPMC6456736 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature