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

• 来源期刊: 光：科学与应用（英文版）
• 年，卷（期）: 2019,（3）
• 页码范围: 341-349
• 页数: 9页
• 语种: 英文

摘要

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.Na0.5K0.5Li3SiO4∶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 ℃.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.