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Updated: Jul 24, 2025
Low-energy Cathodoluminescence for OxyNitride Phosphors
Published on: November 15, 2016
Ultra-broad Near-Infrared Emitting Phosphor LiInF4: Cr3+ with Extremely Weak Crystal Field
Liping Song1,2,3,4, Sisi Liang3,4, Wendong Nie3,4
1School of Rare Earths, University of Science and Technology of China, Hefei, Anhui 230026, China.
Abstract:
Recent decades have witnessed a major development in broadband near-infrared (NIR)-emitting phosphors because of their potential applications in real-time nondestructive examination. These applications require the emission spectra of phosphors to be as broad as possible for efficient performance. Therefore, a blue-light excited LiInF4: Cr3+ phosphor with a NIR emission covering 700-1400 nm is successfully synthesized. Under 470 nm excitation, it shows broadband emission peaked at 980 nm with the full-width at half maximum of 210 nm. The structure and crystal field environment are investigated in detail, and the LiInF4: Cr3+ possesses a weak crystal field strength and strong electron-phonon coupling. An efficient NIR phosphor-converted light-emitting diode (pc-LED) is fabricated by the prepared LiInF4: Cr3+ phosphor and commercial blue diode chip, generating a NIR radiant flux of 5.54 mW at 150 mA drive current. Finally, the NIR pc-LED is successfully applied to identify the blood vessel distribution of the hand. This work suggests the potential of LiInF4: Cr3+ phosphor in applications.
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