Double‐Site Occupation Triggered Broadband and Tunable NIR‐I and NIR‐II Luminescence in AlNbO4:Cr3+ Phosphors. Issue 4 (15th December 2022)

• Record Type: Journal Article
• Authors: Lyu, Kuangnan; Liu, Gaochao; Molokeev, Maxim S.; Xia, Zhiguo
• Is Part Of: ADVANCED PHYSICS RESEARCH. Volume 2:Issue 4(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-12-15
• Subjects: near‐infrared luminescence -- phosphor -- site occupation -- tunable emissions; 530
• DOI: 10.1002/apxr.202200056
• Languages: English
• ISSNs: 2751-1200

Abstract

Abstract: Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) are desired for optoelectronic and biomedical applications, while the development of target broadband NIR phosphors still remains a significant challenge. Herein, a kind of Cr 3+ ‐doped AlNbO4 phosphors with a broad NIR emission ranging from 650 to 1400 nm under 450 nm excitation are reported. A giant red‐shift emission peak from 866 to 1020 nm together with broadened full width at half‐maximum of 320 nm is achieved simply by varying the doped Cr 3+ concentrations. Structural and spectroscopy analysis demonstrate that a concentration‐dependent site‐occupation of Cr 3+ emitters in different Al 3+ sites is responsible for the tunable NIR luminescence. The as‐fabricated NIR pc‐LED based on optimized AlNbO4 :Cr 3+ phosphor exhibits great potential in night‐vision applications. This work provides a novel design principle on the Cr 3+ ‐doped AlNbO4 phosphor with tunable broadband luminescence from NIR‐I to NIR‐II, and these materials can be employed in NIR spectroscopy applications. Abstract : Al1− x NbO4 : x Cr 3+ phosphors exhibit broadband near‐infrared (NIR) emissions with a dramatic redshift with an increase of Cr 3+ concentration， which is attributed to double Cr 3+ emission centers, comfirmed by structural and spectral analysis. The NIR phosphor‐converted light‐emitting diode device is fabricated and a night‐visible image and transmittance spectra are captured, suggesting potential for NIR spectroscopy applications.