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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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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Structural Rigidity Control toward Cr³⁺-Based Broadband Near-Infrared Luminescence with Enhanced Thermal Stability

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(3), P. 1376 - 1384

Published: Jan. 19, 2022

Broadband near-infrared (NIR) light sources based on phosphor-converted light-emitting diodes (pc-LEDs) are desirable for biochemical analysis and medical diagnosis applications; however, the development of target NIR phosphor is still a challenge. Herein, broadband phosphors, Cr3+-activated CaSc1–xAl1+xSiO6 (λem = 950 nm), designed optimized by chemical substitution toward enhanced quantum efficiency thermal stability. Structural spectral analyses along with density functional theory calculations reveal that Sc3+/Al3+ contributes to enhancing structural rigidity local symmetry [Sc/AlO6] octahedron so nonradiative relaxation Cr3+ emission centers suppressed significantly. The as-fabricated phosphor-in-glass-based LED source demonstrates great potential in detection alcohol concentration. This study provides structure design principle exploring phosphors stability will also stimulate further studies material discovery quantitative spectroscopy.

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 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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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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Modulation of Thermally Stable Photoluminescence in Cr³⁺-Based Near-Infrared Phosphors

The Journal of Physical Chemistry Letters, Journal Year: 2022, Volume and Issue: 13(22), P. 5001 - 5008

Published: June 1, 2022

Broadband near-infrared (NIR) light sources based on phosphor-converted light-emitting diodes (pc-LEDs) are desirable for various photonics applications, while developing thermally stable NIR phosphors remains a great challenge. Increasing the temperature accelerates severe nonradiative relaxation process gorverned by intrinsic energy gap law, which further suspends efficient low-energy emission of Cr3+ emitters in inorganic lattice. To address this rule, several state-of-the-art strategies have been put forward perspective to modulate critical law from viewpoints (1) crystal structure design, (2) defect engineering, (3) strengthened rigidity, and (4) transfer. This suggests avenues exploring novel broadband with high thermal stability will also stimulate studies spectroscopy high-power applications.

Language: Английский

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Highly Efficient Broadband Near-Infrared Luminescence with Zero-Thermal-Quenching in Garnet Y₃In₂Ga₃O₁₂:Cr³⁺ Phosphors

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(18), P. 8418 - 8426

Published: Sept. 15, 2022

Broadband near-infrared (NIR) light source based on phosphor-converted light-emitting-diode (pc-LED) is crucial for applications in medical diagnosis, food quality analysis, and night vision fields, motivating the development of highly efficient thermal robust NIR phosphor materials. Herein, a novel Cr3+-doped garnet Y3In2Ga3O12:Cr3+ emerges from fundamental study Ln3In2Ga3O12 (Ln = La, Gd, Y, Lu) family. Upon 450 nm excitation, this material presents broadband emission covering 650–1100 with peak located at 760 full width half maximum 125 nm. This also possesses an ultrahigh internal quantum efficiency (IQE 91.6%) absorption (AE 46.6%), resulting external as high 42.7%. Moreover, intensity 150 °C maintains 100% initial intensity, showing rare zero-thermal-quenching property. Fabricating pc-LED device by using material, excellent output power 68.4 mW photoelectric 15.9% under mA driving current can be obtained, which exhibits much better performance than devices fabricated some reported Therefore, work not only provides ultraefficient thermally spectroscopy application but contributes to foundation design rules materials performance.

Language: Английский

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Photoluminescence Properties of AScSi₂O₆:Cr³⁺ (A = Na and Li) Phosphors with High Efficiency and Thermal Stability for Near-Infrared Phosphor-Converted Light-Emitting Diode Light Sources

ACS Applied Materials & Interfaces, Journal Year: 2022, Volume and Issue: 14(6), P. 8179 - 8190

Published: Feb. 3, 2022

Near-infrared (NIR) phosphors are fascinating photoluminescence materials with applications in phosphor-converted light-emitting diodes (pc-LEDs) for night vision lighting, which still restricted by low efficiency and thermal stability the current research stage. In this work, AScSi2O6 (A = Na/Li) chosen as hosts due to a larger band gap single octahedral site Cr3+ doping. The NIR-emitting Cr3+-activated AScSi2O6:Cr3+ were successfully prepared common high-temperature solid-state method. X-ray diffraction Rietveld refinement confirm that prefers enter Sc3+-octahedral lattice structure. Under blue light excitation, exhibit broadband NIR emission from 700 1100 nm full width at half-maximum of ∼150 owing 4T2 → 4A2 electron transition Cr3+. properties enhanced adjusting fluxes sintering conditions, highly efficient LiScSi2O6:Cr3+ external quantum efficiencies 33.4% obtained. Moreover, optimized exhibits excellent (75% 150 °C) an activation energy 0.33 eV. Importantly, fabricated pc-LED phosphor demonstrates brighter higher luminous efficacy than NaScSi2O6:Cr3+ vision.

Language: Английский

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