Advances in Chromium‐Activated Phosphors for Near‐Infrared Light Sources

Laser & Photonics Review, Journal Year: 2022, Volume and Issue: 16(11)

Published: Aug. 7, 2022

Abstract Cr 3+ /Cr 4+ ‐activated near‐infrared (NIR) luminescent materials have attracted extensive attention owing to their tunable emission wavelength and widespread applications in plant growth, food analysis, biomedical imaging, night vision, so on. Plenty of excellent NIR are developed by introducing ion various inorganic hosts. Herein, the effect crystal field on luminescence combining Tanabe–Sugano energy level diagram configuration coordinate model is discussed. Research progress ‐doped materials, including phosphors designed from structural models with octahedral, tetrahedral, other coordination types, then outlined. The properties more than 200 kinds summarized. In particular, several strategies for tuning wavelength, broadening band, enhancing efficiency, improving thermal stability, listed. Finally, current challenges future prospects research presented. This review will contribute a deeper understanding not only mechanism but also chromium‐doped as develop better performance explore applications.

Language: Английский

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Simultaneous Broadening and Enhancement of Cr³⁺Photoluminescence in LiIn₂SbO₆by Chemical Unit Cosubstitution: Night‐Vision and Near‐Infrared Spectroscopy Detection Applications

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(26), P. 14644 - 14649

Published: April 6, 2021

Abstract Near‐infrared (NIR)‐emitting phosphor materials have been extensively developed for optoelectronic and biomedical applications. Although Cr 3+ ‐activated phosphors widely reported, it is challenging to achieve ultra‐broad tunable NIR emission. Here, a new ultra‐broadband NIR‐emitting LiIn 2 SbO 6 :Cr with emission peak at 965 nm full‐width half maximum of 217 reported. Controllable tuning from 892 achieved by chemical unit cosubstitution [Zn 2+ –Zn ] [Li + –In ], which can be ascribed the upshift 4 T 2g energy level due strengthened crystal field. Moreover, greatly enhanced, FWHM reaches 235 nm. The as‐prepared luminescent demonstrated potential in night‐vision spectroscopy techniques. This work proves feasibility strategy ‐doped phosphors, stimulate further studies on emission‐tunable materials.

Language: Английский

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A highly efficient and suitable spectral profile Cr3+-doped garnet near-infrared emitting phosphor for regulating photomorphogenesis of plants

Chemical Engineering Journal, Journal Year: 2021, Volume and Issue: 428, P. 132003 - 132003

Published: Aug. 25, 2021

Language: Английский

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Structural Confinement for Cr³⁺ Activators toward Efficient Near-Infrared Phosphors with Suppressed Concentration Quenching

Chemistry of Materials, Journal Year: 2021, Volume and Issue: 33(10), P. 3621 - 3630

Published: May 4, 2021

Trivalent chromium ion-doped near-infrared (NIR) phosphors have been widely studied due to their tunable emission wavelengths and broad applications. High Cr3+ concentration can improve absorption efficiency but generally results in low intensity the quenching effect. Herein, we report a series of efficient NIR with suppressed quenching, Sr9M1–x(PO4)7:xCr3+ (M = Ga, Sc, In, Lu), showing broadband ranging from 700 1100 nm peaking at 850 upon 485 light excitation. The peak position is almost independent type M ion dopant content, has little influence on luminescence thermal indicating that [MO6] octahedra are rigid enough keep octahedral volumes average M3+–O2– distances nearly constant owing formation framework structure substitution. intensities monotonously increase content increasing 0 80% Sr9Cr(PO4)7 still maintains 84.23% Sr9Ga0.2(PO4)7:0.8Cr3+ phosphor, behavior slightly dependent x; these effects be attributed energy transfer structural confinement optimal sample, Sr9Ga0.2(PO4)7:0.8Cr3+, an internal/external quantum 66.3%/29.9%. Finally, fabricate phosphor-conversion light-emitting diode demonstrate its applications nondestructive examination medical fields.

Language: Английский

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Efficient and Broadband LiGaP₂O₇:Cr³⁺ Phosphors for Smart Near‐Infrared Light‐Emitting Diodes

Laser & Photonics Review, Journal Year: 2021, Volume and Issue: 15(11)

Published: Oct. 11, 2021

Abstract Broadband near‐infrared (NIR) phosphor‐converted (pc) LED is promising next‐generation tiny light source for smart and broadband NIR spectroscopy technology. However, phosphors suffer from challenges in terms of low quantum efficiency bandwidth. By selecting a host that has big bandgap weakening coupling effect among Cr 3+ , novel LiGaP 2 O 7 :Cr (LGAP:Cr ) phosphor high external (28.3%) discovered. Under ≈450 nm excitation, LGAP:Cr shows broad emission 700 to 1100 with bandwidth ≈170 nm. Importantly, the fabricated pcLED demonstrates bright an excellent performance night vision. The results promise use high‐performance employs only one blue chip.

Language: Английский

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A General Ammonium Salt Assisted Synthesis Strategy for Cr³⁺‐Doped Hexafluorides with Highly Efficient Near Infrared Emissions

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(36)

Published: June 24, 2021

Abstract The discovery of highly efficient broadband near infrared (NIR) emission material is urgent and crucial for constructing NIR lighting sources emerging applications. Herein, a series hexafluorides A 2 BMF 6 :Cr 3+ (A = Na, K, Rb, Cs; B Li, M Al, Ga, Sc, In) peaking at ≈733–801 nm with full width half maximum (FWHM) ≈98–115 are synthesized by general ammonium salt assisted synthesis strategy. Benefiting from the pre‐ammoniation trivalent metal sources, Cr can be more efficiently doped into simultaneously prevent generation competitive phase. Particularly, Na 3 ScF (λ em 774 nm, FWHM ≈ 108 nm) optimal ‐doping concentration 35.96% shows high internal quantum efficiency 91.5% an external ≈40.82%. emitting diode (LED) device output power ≈291.05 mW 100 mA driven current photoelectric conversion 20.94% fabricated. strategy opens up new avenues exploration ‐doped phosphors, as‐obtained record demonstrates LED

Language: Английский

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Ultra-Broadband and high efficiency Near-Infrared Gd3Zn Ga5-2Ge O12:Cr3+ (x = 0–2.0) garnet phosphors via crystal field engineering

Chemical Engineering Journal, Journal Year: 2022, Volume and Issue: 437, P. 135346 - 135346

Published: Feb. 19, 2022

Language: Английский

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Recent Advances in Chromium‐Doped Near‐Infrared Luminescent Materials: Fundamentals, Optimization Strategies, and Applications

Advanced Optical Materials, Journal Year: 2022, Volume and Issue: 11(3)

Published: Dec. 5, 2022

Abstract Development of chromium‐doped luminescent materials is pertinent to many emerging applications, ranging from agriculture, food industry noninvasive health monitoring. The fundamental importance chromium‐activated in the field optics and biomedicine makes rapid development novel relevant applications. Herein, recent advances on luminescence principle photoluminescence (PL) optimization for Cr 3+ ‐activated together with their potential applications are reviewed. different types most recently developed ‐doped design principles systematically summarized. associations between crystal structure near‐infrared (NIR) PL properties, as well performance‐evaluating parameters introduced examples known NIR emitting phosphors, which will be helpful explore future materials. Based control, site engineering, electron–phonon coupling, several efficient strategies optimizing performances including bandwidth, thermal stability, quantum efficiency proposed. Then, fields analysis, night vision, information encryption, optical sensors surveyed. Finally, challenges promising

Language: Английский

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How to Obtain Anti‐Thermal‐Quenching Inorganic Luminescent Materials for Light‐Emitting Diode Applications

Advanced Optical Materials, Journal Year: 2022, Volume and Issue: 10(6)

Published: Jan. 17, 2022

Abstract Phosphor‐converted light‐emitting diode (pc‐LED) has drawn much interest due to the efficient light in solid‐state lighting, backlight display, security, and electronic devices. Thermal quenching (TQ) induced by nonradiative relaxation is one of vital challenges that limits widespread use phosphors. Much efforts are devoted designing different approaches solve emission loss at increasing temperature. Here, mechanism TQ recent advances anti‐TQ‐phosphor‐involved 5d–4f, 4f–4f, 6p–6s, 3d–3d transitions discussed. Several important design strategies for anti‐TQ phosphors summarized as follows: 1) defect engineering; 2) energy transfer; 3) structural modulation; 4) enhancing crystallinity; 5) layer design; 6) negative/zero thermal expansion; 7) surface coating glass technology. Additionally, some future opportunities this field proposed. This review promotes discovery novel phosphor materials LED applications.

Language: Английский

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Efficient and Thermally Stable Broad-Band Near-Infrared Emission in a KAlP₂O₇:Cr³⁺ Phosphor for Nondestructive Examination

ACS Applied Materials & Interfaces, Journal Year: 2022, Volume and Issue: 14(9), P. 11663 - 11671

Published: Feb. 23, 2022

Broad-band near-infrared (NIR) phosphors are essential to assembling portable NIR light sources for applications in spectroscopy technology. However, developing inexpensive, efficient, and thermally stable broad-band remains a significant challenge. In this work, phosphate, KAlP2O7, with wide band gap suitable electronic environment Cr3+ equivalent substitution was selected as the host material. The synthesized KAlP2O7:Cr3+ material exhibits emission covering 650-1100 nm peak centered at 790 full width half-maximum (fwhm) of 120 under 450 excitation. internal quantum efficiency (IQE) determined be 78.9%, intensity 423 K still maintains 77% that room temperature, implying high excellent thermal stability Finally, phosphor-converted light-emitting diode (pc-LED) device fabricated by using as-prepared combined blue LED chip, which presents output power 32.1 mW photoelectric conversion 11.4% drive current 100 mA. Thus, work not only provides an inexpensive performance pc-LEDs but also highlights some strategies explore class materials.

Language: Английский

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