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Abstract Efficient broadband near‐infrared (NIR) emitting materials with an emission peak centered above 830 nm are crucial for smart NIR spectroscopy‐based technologies. However, the development of these materials remains a significant challenge. Herein, a series of design rules rooted in computational methods and empirical crystal‐chemical analysis is applied to identify a new Cr3+‐substituted phosphor. The compound GaTaO4:Cr3+emerged from this study is based on the material's high structural rigidity, suitable electronic environment, and relatively weak electron–phonon coupling. Irradiating this new phosphor with 460 nm blue light generates a broadband NIR emission (λem,max = 840 nm) covering the 700–1100 nm region of the electromagnetic spectrum with a full width at half maximum of 140 nm. The phase has a high internal quantum yield of 91% and excellent thermal stability, maintaining 85% of the room temperature emission intensity at 100 °C. Fabricating a phosphor‐converted light‐emitting diode device shows that the new compound generates an intense NIR emission (178 mW at 500 mA) with photoelectric efficiency of 6%. This work not only provides a new material that has the potential for next‐generation high‐power NIR applications but also highlights a set of design rules capable of developing highly efficient long‐wavelength broadband NIR materials.
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Organic NIR Photodetectors: Pushing Photodiodes Beyond 1000 nm
Advances in the synthesis of low bandgap (Eg < 1.5 eV) conjugated polymers has produced organic materials capable of absorbing near-infrared (NIR) light (800—2500 nm), with these materials first applied to photodiode NIR detectors in 2007 as an alternative to more traditional inorganic devices. Although the development of organic NIR photodetectors has continued to advance, their ability to effectively detect wavelengths in the low-energy portion of the NIR spectrum is still limited. Efforts to date concerning the production of photodiode-based devices capable of detecting light beyond 1000 nm are reviewed.
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- Award ID(s):
- 2002877
- PAR ID:
- 10250243
- Date Published:
- Journal Name:
- General chemistry
- Volume:
- 7
- Issue:
- 2
- ISSN:
- 2414-3421
- Page Range / eLocation ID:
- 200019
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.21127/yaoyigc20200039
