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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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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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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Dopant and Compositional Modulation Triggered Broadband and Tunable Near-Infrared Emission in Cs₂Ag_1–xNa_xInCl₆:Cr³⁺ Nanocrystals

Chemistry of Materials, Journal Year: 2022, Volume and Issue: 34(7), P. 3006 - 3012

Published: March 29, 2022

Lead-free halide perovskite nanocrystals (NCs) have attracted more attention and demonstrated versatile potential in optoelectronic applications. However, achieving broadband near-infrared (NIR) emission such materials remains a challenge. Herein, we successfully obtained Cr3+-doped Cs2AgInCl6 NCs via hot-injection synthesis, which exhibits NIR with large full width at half-maximum of 193 nm. Furthermore, tunable from 998 to 958 nm along an enhanced photoluminescence quantum yield 19.7% is realized by gradually substituting Ag+ Na+, the blue shift luminescence behavior attributed strengthened crystal field around Cr3+. The excellent chemical moisture stability together as-fabricated Cs2NaInCl6:Cr3+ NC film made screen printing showcases its application high-resolution images fluorescent signs. This work proves possibility realizing lead-free provides guidance for expanding their region.

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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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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Efficient Broadband Near-Infrared CaMgGe₂O₆:Cr³⁺ Phosphor for pc-LED

Inorganic Chemistry, Journal Year: 2022, Volume and Issue: 61(23), P. 8815 - 8822

Published: June 1, 2022

Broadband near-infrared (NIR) phosphor-converted light-emitting diodes (pc-LEDs) are essential to integrate spectrometers into mobile devices for the rapid and noninvasive detection of biological components. However, efficient broadband NIR phosphors with a peak emission wavelength longer than 800 nm deficient. In this study, CaMgGe2O6:Cr3+ phosphor was prepared by high-temperature solid-state reaction. The doped 0.02Cr3+ showed an band at 845 broad bandwidth 160 high quantum yield 84% under 450 excitation. pc-LED fabricated using CaMgGe2O6:0.02Cr3+ based on blue diode (LED) chip. A photoelectric efficiency 27.2% @ 10 mA output power 57.98 mW 100 were achieved, which highest values reported yet pc-LEDs nm. Using as light source, characteristic absorption spectra some substances obtained. All results indicated that has considerable potential in spectroscopic applications.

Language: Английский

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Broadband NIR-II phosphors with Cr4+ single activated centers based on special crystal structure for nondestructive analysis

Ceramics International, Journal Year: 2022, Volume and Issue: 48(18), P. 26884 - 26893

Published: June 2, 2022

Language: Английский

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How to Achieve Excellent Luminescence Properties of Cr Ion‐Doped Near‐Infrared Phosphors

Advanced Optical Materials, Journal Year: 2023, Volume and Issue: 11(24)

Published: Oct. 11, 2023

Abstract Transition metal chromium (Cr) ion‐doped inorganic materials exhibit distinct tunable broadband near‐infrared luminescence, and they have promising applications including nondestructive composition analysis, night vision, biomedicine, plant illumination, afterglow anticounterfeiting. Currently, the most critical issue is to optimize their full width at half maxima, thermal stability, internal/external quantum efficiency. This review systematically summarizes strategies effectively improve photoluminescence performance of near‐infrared‐emitting with transition ions. Key examples design preparation Cr luminescence different modes, a detailed discussion properties luminescent materials, summary generic help explore novel efficient Cr‐doped phosphor are provided. Next, latest developments trends in these presented for variety application scenarios. Finally, future research directions new challenges faced also discussed.

Language: Английский

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