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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Efficient Broadband Near‐Infrared Emission in the GaTaO₄:Cr³⁺ Phosphor

Advanced Optical Materials, Journal Year: 2021, Volume and Issue: 10(2)

Published: Nov. 1, 2021

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 remains a significant challenge. Herein, series design rules rooted in computational methods and empirical crystal‐chemical analysis is applied to identify new Cr 3+ ‐substituted phosphor. The compound GaTaO 4 :Cr emerged from this study based on material's high structural rigidity, suitable electronic environment, relatively weak electron–phonon coupling. Irradiating phosphor 460 blue light generates (λ em,max = 840 nm) covering 700–1100 region electromagnetic spectrum full width at half maximum 140 nm. phase has internal quantum yield 91% excellent thermal stability, maintaining 85% room temperature intensity 100 °C. Fabricating phosphor‐converted light‐emitting diode device shows that intense (178 mW 500 mA) photoelectric efficiency 6%. This work not only provides material potential next‐generation high‐power applications but also highlights set capable developing highly efficient long‐wavelength materials.

Language: Английский

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Achieving High Quantum Efficiency Broadband NIR Mg₄Ta₂O₉:Cr³⁺ Phosphor Through Lithium‐Ion Compensation

Advanced Materials, Journal Year: 2023, Volume and Issue: 35(22)

Published: March 3, 2023

Ultra-efficient broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are urgently needed to improve the detection sensitivity and spatial resolution of current smart NIR spectroscopy-based techniques. Nonetheless, performance pc-LED has severely limited owing external quantum efficiency (EQE) bottleneck materials. Herein, a blue LED excitable Cr3+ -doped tetramagnesium ditantalate (Mg4 Ta2 O9 , MT) phosphor is advantageously modified through lithium ion as key efficient emitter achieve high optical output power light source. The emission spectrum encompasses 700-1300 nm electromagnetic first biological window (λmax = 842 nm) with full-width at half-maximum (FWHM) ≈2280 cm-1 (≈167 nm), achieves record EQE 61.25% detected 450 excitation Li-ion compensation. A prototype fabricated MT:Cr3+ Li+ evaluate its potential practical application, which reveals an 53.22 mW driving 100 mA, photoelectric conversion 25.09% 10 mA. This work provides ultra-efficient luminescent material, shows great promise in applications presents novel option for next-generation high-power compact sources.

Language: Английский

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Super Broadband Emission Across NIR‐I and NIR‐II Under Blue Light Excitation of Cr³⁺, Ni²⁺ Co‐Doped Sr₂GaTaO₆ Phosphor Achieved by Two‐Site Occupation and Effective Energy Transfer

Laser & Photonics Review, Journal Year: 2024, Volume and Issue: 18(8)

Published: March 20, 2024

Abstract The performance of the near‐infrared phosphor‐converted light‐emitting diodes (NIR pc‐LEDs) mainly depends on NIR emitting phosphors used. Cr 3+ doped materials can be excited by blue light chips, but their emission is located in NIR‐I region (650–1000 nm). Ni 2+ are NIR‐II (1000–1700 nm), they cannot effectively chips. Herein, , mono‐doped, and co‐doped Sr 2 GaTaO 6 prepared investigated. ions occupy two octahedral sites Ga Ta 5+ . co‐doping has achieved breakthroughs. One to shift optimal excitation wavelength from violet due energy transfer (efficiency up 70%) other achieve broadband continuous across regions (650–1700 nm, with a full width at half maximum (FWHM) 410 nm (173 + 237 nm)). : 0.02Cr 0.01Ni phosphor combined commercial 460 chip realize its application organic compounds identification, night vision, biological imaging. This work points out direction for future development efficient super NIR‐emitting phosphors.

Language: Английский

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Achieving Broadband NIR-I to NIR-II Emission in an All-Inorganic Halide Double-Perovskite Cs₂NaYCl₆:Cr³⁺ Phosphor for Night Vision Imaging

ACS Applied Materials & Interfaces, Journal Year: 2023, Volume and Issue: 15(33), P. 39550 - 39558

Published: Aug. 10, 2023

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) offer numerous advantages, including compact size, tunable emission spectra, energy efficiency, and high integration potential. These features make them highly promising for various applications, such as night vision monitoring, food safety inspection, biomedical imaging, theragnostics. All-inorganic halide double-perovskite materials, known their large absorption cross section, excellent defect tolerance, long carrier diffusion radius, serve unique matrices constructing near-infrared fluorescent materials. In this study, we successfully prepared the all-inorganic metal Cs2NaYCl6:Cr3+ using a grinding-sintering method. A small fraction of [YCl6] octahedra within host material's lattice was substituted with Cr3+ ions, resulting in creation phosphor. When excited λ = 310 nm UV light, phosphor exhibited broad range spanning from 800 to 1400 nm, covering NIR-I NIR-II regions. It had bandwidth 185 achieved fluorescence quantum yield 20.2%. The broadband originates weak crystal field environment provided by Cs2NaYCl6 matrix, which enhances luminescence properties ions. To create NIR pc-LEDs, encapsulated onto commercially available LED chip operating at nm. potential application these pc-LEDs imaging validated.

Language: Английский

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High Output Power and High Quantum Efficiency in Novel NIR Phosphor MgAlGa_0.7B_0.3O₄:Cr³⁺ with Profound FWHM Variation

Advanced Materials, Journal Year: 2023, Volume and Issue: 36(9)

Published: Nov. 8, 2023

Abstract There is strong demand for ultraefficient near‐infrared (NIR) phosphors with adjustable emission properties next‐generation intelligent NIR light sources. Designing large full‐width at half‐maximum (FWHM) variations challenging. In this study, novel near‐ultraviolet light‐emitting diode (LED)‐excited phosphors, MgAlGa 0.7 B 0.3 O 4 :Cr 3+ (MAGBO:Cr ), three centers achieve ultra‐narrowband (FWHM = 29 nm) to ultra‐broadband 260 increasing Cr concentration. Gaussian fitting and decay time analysis reveal the alteration in FWHM, which attributed energy transfer occurring between centers. The distinct thermal quenching behaviors of are revealed through temperature‐dependent times. phosphor MAGBO:0.05Cr exhibits high stability (85%, 425 K) exceptional external quantum efficiency 68.5%. An phosphor‐converted LED (pc‐LED) fabricated using phosphor, exhibiting a remarkable output power 136 mW 600 mA pc‐LEDs. This study describes preparation highly efficient provides further understanding tunable vital high‐performance versatile 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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Cr³⁺-doped borate phosphors for broadband near-infrared LED applications

Inorganic Chemistry Frontiers, Journal Year: 2022, Volume and Issue: 9(10), P. 2240 - 2251

Published: Jan. 1, 2022

A novel broadband NIR phosphor K 6 Li 0.9 Na 0.1 CaSc 2 (B 5 O 10 ) 3 :Cr 3+ with a single luminescence center has been successfully synthesized, and the relationship between crystal structure properties was systematically investigated.

Language: Английский

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Producing Tunable Broadband Near-Infrared Emission through Co-Substitution in (Ga_1–xMg_x)(Ga_1–xGe_x)O₃:Cr³⁺

ACS Applied Materials & Interfaces, Journal Year: 2022, Volume and Issue: 14(45), P. 51157 - 51164

Published: Nov. 7, 2022

Broadband near-infrared (NIR) phosphors are in high demand for creating "smart" NIR phosphor-converted light-emitting diode (pc-LED) sources. In this work, a series of Cr3+-substituted NIR-emitting materials with highly efficient, broad, tunable emission spectra achieved by modifying the simple oxide Ga2O3 using [Mg2+-Ge4+] and [Ga3+-Ga3+] co-unit substitution. The results show that peak can be shifted from 726 to 830 nm while maintaining constant excitation blue light region, enabling extensive application. optical properties stem changes Cr3+ crystal field environment upon Intriguingly, temperature-dependent photoluminescence position shows virtually no change co-substituted materials. This abnormal phenomenon is found comprehensive embodiment weakening (red-shift) as temperature increases reduced local structure distortion (blue-shift) increasing temperature. quantum yield, emission, net-zero shift function make phosphor class optimal device incorporation. As result, their performance was studied coating on 450 emitting LED chip. fabricated demonstrates an excellent output power photoelectric conversion efficiency. study provides tunable, broadband spectroscopy applications contributes basic foundation Cr3+-activated phosphors.

Language: Английский

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