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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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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Broadband Near-Infrared Luminescence in Garnet Y₃Ga₃MgSiO₁₂: Cr³⁺ Phosphors

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(10), P. 4220 - 4226

Published: March 1, 2023

Broadband near-infrared (NIR) phosphors are the critical component of phosphor converted NIR light-emitting diode (LED) light sources. However, there still a lack with excellent external quantum efficiency (EQE) and thermal stability. Here, we report highly efficient broadband Y3Ga3MgSiO12: Cr3+. The optimized yields an internal (IQE) EQE 79.9 33.7%, respectively. integrated emission intensity remains at 84.4% that room temperature when heated to 423 K. A LED lamp was made by combining as-prepared blue InGaN chip, which shows output power 89.8 mW photoelectric conversion 17.1% driven 525 input power. Our research provides promising high for source.

Language: Английский

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Broadband and Multimode Near‐Infrared Emitter Based on Cr³⁺‐Activated Stannate for Multifunctional Applications

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(7)

Published: Jan. 19, 2023

Abstract Broadband near‐infrared (NIR) phosphors have recently received considerable attention in spectroscopy technology fields, but designing inexpensive, emission peaks centered above 800 nm, and multimodal broadband NIR luminescence material still remains a great challenge. Here, by selecting stannate compound Mg 2 SnO 4 (MSO) as the host, kind of phosphor MSO:Cr 3+ with multimode properties is reported. The designed exhibits an peaking at nm full‐width half maximum 180 (≈2730 cm −1 ). site occupation Cr MSO unraveled density functional theory calculation. constructed light‐emitting device based on displays high output power 187.19 mW@100 mA remarkable photoelectric efficiency 13.67%, its multifunctional applications information encryption, non‐destructive detection, so are also demonstrated. Additionally, through defect reconstruction, presents superior persistent (PersL) PersL duration time longer than 50 h. This work provides feasible strategy to develop intelligent optical integrated low‐cost compounds host toward versatile such detection bioimaging.

Language: Английский

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Unlocking Cr³⁺–Cr³⁺ Coupling in Spinel: Ultrabroadband Near-Infrared Emission beyond 900 nm with High Efficiency and Thermal Stability

ACS Applied Materials & Interfaces, Journal Year: 2024, Volume and Issue: 16(23), P. 30185 - 30195

Published: May 31, 2024

Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) hold promising potential as next-generation compact, portable, and intelligent NIR light sources. Nonetheless, the lack of high-performance broadband phosphors with an emission peak beyond 900 nm has severely hindered development widespread application pc-LEDs. This study presents a strategy for precise control energy-state coupling in spinel solid solutions composed MgxZn1–xGa2O4 to tune emissions Cr3+ activators. By combining crystal field engineering heavy doping, Cr3+–Cr3+ ion pair from 4T2 state is unlocked, giving rise unusual spanning 650 1400 maximum 913 full width at half-maximum (fwhm) 213 nm. Under optimal Mg/Zn ratio 4:1, sample achieves record-breaking performance, including high internal external quantum efficiency (IQE = 83.9% EQE 35.7%) excellent thermal stability (I423 K/I298 K 75.8%). Encapsulating as-obtained into prototype pc-LEDs yields overwhelming output power 124.2 mW driving current 840 mA photoelectric conversion (PCE) 10.5% 30 mA, rendering performance imaging applications.

Language: Английский

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Developing the Na₂CaZr₂Ge₃O₁₂:Cr³⁺ Garnet Phosphor for Advanced NIR pc-LEDs in Night Vision and Bioimaging

Chemistry of Materials, Journal Year: 2024, Volume and Issue: 36(9), P. 4654 - 4663

Published: May 1, 2024

Materials emitting near-infrared (NIR) light play a crucial role in the development of phosphor-converted light-emitting diodes (pc-LEDs) for applications ranging from fundamental science like spectroscopic analysis to highly applied uses night vision and biological imaging. One class materials that has garnered significant interest these technical spaces is Cr3+-activated garnets due their high efficiency ability operate at relatively temperatures. However, limited emission beyond 800 nm impedes use as optimal blue LED-pumped NIR-emitting materials. In this study, we present new garnet-type NIR phosphor, Na2CaZr2Ge3O12:Cr3+, addresses challenge─the material exhibits long-wavelength (λem,max = 832 nm) good thermal quenching resistance while maintaining an excellent internal quantum (IQE 98%). These properties are attributed crystal environment reconstruction, where structure distortion coupled weak field, which uncommon most rigid phosphors. Furthermore, fabricated pc-LED devices using demonstrate superior performance compared with employing well-known efficient phosphors operating range. The source subsequently demonstrated spanning vision, bioimaging, nondestructive analysis. This study not only provides insights into luminescence garnet desirable but also highlights practical application

Language: Английский

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Thermally-stable and color-tunable novel single phase phosphor Ca2GaTaO6:Dy3+, Sm3+ for indoor lighting applications

Ceramics International, Journal Year: 2024, Volume and Issue: 50(9), P. 14188 - 14199

Published: Jan. 25, 2024

Language: Английский

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Highly Efficient and Thermally Stable Broadband NIR Phosphors with Superlong Afterglow Performance and their Multifunctional Applications

Laser & Photonics Review, Journal Year: 2024, Volume and Issue: 18(10)

Published: May 16, 2024

Abstract Near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) are considered as promising next‐generation light sources for optoelectronic and biomedical applications. Nevertheless, NIR phosphors with large bandwidths, long emission peaks, high external quantum efficiencies (EQEs) valuable thermal stabilities challenging to develop. Herein, this study reports a novel gallium germanate host, Ga 3 Al Ge 2 O 13 (GAGO), bandgap rigid host lattice Cr 3+ ion doping. The blue LED excitable GAGO:0.012Cr phosphor can produce broadband maximum intensity at 816 nm full‐width half‐maximum (FWHM) of 187 nm. Notably, the also exhibits an excellent EQE 35.8% perfect stability (I 423 K /I 298 = 67.4%). Moreover, attractive afterglow duration more than 24 h is achieved in GAGO:0.004Cr phosphor. type origin traps discussed, possible persistent luminescent (LPL) mechanism proposed. Finally, pc‐LED based on fabricated. results demonstrate that obtained show great potential use night vision, nondestructive detection, bioimaging information encryption. This provides new insight into development materials efficiency, good extraordinary performance.

Language: Английский

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Blueshift and Photoluminescence Enhancement in Broadband Near‐Infrared Emitting Phosphor NaSr₂(Al/Ga)Ge₅O₁₄: Cr³⁺ Dependence on the Sc/In Substitution

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(13)

Published: Jan. 26, 2024

Abstract Cr 3+ ‐activated near‐infrared (NIR) phosphors have gained extensive attention for use in NIR phosphor‐converted light‐emitting diodes (pc‐LEDs), which are required smart spectroscopy techniques. Nevertheless, obtaining broadband NIR‐emitting with outstanding thermal stabilities and photoluminescence (PL) efficiencies remains a significant challenge. Herein, considering NaSr 2 XGe 5 O 14 (X = Al, Ga, Sc, In) as hosts, possess large band gap multiple sites the substitution of ions. :Cr successfully prepared using solid‐state reaction technology. Upon blue light excitation, cover broad emission 650–1100 nm region. Notably, an abnormal blueshift PL enhancement observed following Al/Ga Sc/In. In particular, internal quantum efficiency is improved from 34.5% (NaSr GaGe : ) to 87.5% ScGe ). Moreover, manufactured pc‐LED exhibited exceptional photoelectric 17.7% output power 10.2 mW at 20 mA, its potential application nondestructive detection demonstrated.

Language: Английский

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Site-Selective Occupancy Control of Cr Ions toward Ultrabroad-Band Infrared Luminescence with a Spectral Width up to 419 nm

ACS Applied Materials & Interfaces, Journal Year: 2022, Volume and Issue: 14(47), P. 53101 - 53110

Published: Nov. 17, 2022

Infrared-emitting phosphor-converted light-emitting diodes (LEDs) are desirable light sources for a very wide range of applications such as spectroscopy analysis, nondestructive monitoring, covert information identification, and night-vision surveillance. The most important aspect infrared emitters is to cover the widest possible wavelength emitted light. However, developing ultrabroad-band based on converter technology still challenging task due lack suitable phosphor materials that emit in upon excitation from blue-emitting chips. Herein, this work demonstrates Cr3+-activated Mg2SiO4 phosphors with super spectral 600 1400 nm high internal quantum yield up 80.4% 460 excitation. Site-selective occupancy Cr3+ two different Mg sites lattice results distinct broad emission bands peaking at 760 970 nm, both which contribute luminescence full width half maximum (FWHM) 419 nm. This by far broadest best our knowledge. On basis, an LED prototype has been fabricated combination Mg2SiO4:Cr3+ blue chip, shows great potential imaging sensing applications. site-selective control Cr ions effective strategy Cr3+-doped phosphors.

Language: Английский

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