Two-site Cr³⁺ occupation in the MgTa₂O₆:Cr³⁺ phosphor toward broad-band near-infrared emission for vessel visualization

Journal of Materials Chemistry C, Journal Year: 2020, Volume and Issue: 8(27), P. 9322 - 9328

Published: Jan. 1, 2020

Cr³⁺ ions in MgTa₂O₆ located the two six-coordinated crystallographic sites of Mg²⁺ and Ta⁵⁺ enable broad-band near-infrared emission.

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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Highly efficient Fe3+-doped A2BB′O6 (A = Sr2+, Ca2+; B, B′ = In3+, Sb5+, Sn4+) broadband near-infrared-emitting phosphors for spectroscopic analysis

Light Science & Applications, Journal Year: 2022, Volume and Issue: 11(1)

Published: April 27, 2022

Near-infrared (NIR)-emitting phosphor-converted light-emitting diodes have attracted widespread attention in various applications based on NIR spectroscopy. Except for typical Cr3+-activated NIR-emitting phosphors, next-generation Cr3+-free phosphors with high efficiency and tunable optical properties are highly desired to enrich the types of luminescent materials different application fields. Here, we report Fe3+-activated Sr2-yCay(InSb)1-zSn2zO6 that exhibit unprecedented long-wavelength emission. The overall emission tuning from 885 1005 nm broadened full-width at half maximum 108 146 was realized through a crystallographic site engineering strategy. significantly enhanced after complete Ca2+ incorporation owing substitution-induced lower symmetry Fe3+ sites. Ca2InSbO6:Fe3+ phosphor peaking 935 showed an ultra-high internal quantum 87%. as-synthesized emission-tunable demonstrated great potential spectroscopy detection. This work initiates development efficient broadband opens up new avenue designing materials.

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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High-efficiency blue photoluminescence in the Cs₂NaInCl₆:Sb³⁺ double perovskite phosphor

Journal of Materials Chemistry C, Journal Year: 2020, Volume and Issue: 8(20), P. 6797 - 6803

Published: Jan. 1, 2020

The halide double perovskite Cs₂NaInCl₆ doped with Sb³⁺ is shown to be a promising blue phosphor.

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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Efficient and Tunable Luminescence in Ga_2–xIn_xO₃:Cr³⁺ for Near-Infrared Imaging

ACS Applied Materials & Interfaces, Journal Year: 2021, Volume and Issue: 13(27), P. 31835 - 31842

Published: June 29, 2021

Broadband near-infrared (NIR) emitting materials are in great demand as next-generation smart NIR light sources. In this work, a Cr3+-substituted phosphor capable of efficiently converting visible to is developed through the solid solution, Ga2–xInxO3:Cr3+ (0 ≤ x 0.5). The compounds were prepared using high-temperature solid-state synthesis, and crystal electronic structure, morphology, site preference, photoluminescence properties studied. results demonstrate high quantum yield (88%) impressive absorption efficiency (50%) when = 0.4. emission tunable across wide range (713–820 nm) depending on value x. Moreover, fabricating prototype phosphor-converted light-emitting diode (LED) device 450 nm LED [(Ga1.57Cr0.03)In0.4]O3 showed an output power that reached 40.4 mW with photoelectric conversion 25% driven by current 60 mA, while resulting was able identify damaged produce undetectable light. These outstanding potential for imaging applications.

Language: Английский

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Lead‐Free Halide Double Perovskite Nanocrystals for Light‐Emitting Applications: Strategies for Boosting Efficiency and Stability

Advanced Science, Journal Year: 2021, Volume and Issue: 8(7)

Published: March 3, 2021

Abstract Lead‐free halide double perovskite (HDP) nanocrystals are considered as one of the most promising alternatives to lead due their unique characteristics nontoxicity, robust intrinsic thermodynamic stability, rich and tunable optoelectronic properties. Although lead‐free HDP variants with highly efficient emission synthesized characterized, photoluminescent (PL) properties colloidal still have enormous challenges for application in light‐emitting diode (LED) devices surface defects, indirect band, disallowable optical transitions. Herein, recent progress on synthetic strategies, ligands passivation, metal doping/alloying boosting efficiency stability is comprehensive summarized. It begins by introducing crystalline structure, electronic PL mechanism HDPs. Next, limiting factors origins instability analyzed, followed highlighting effects synthesis Then, preliminary applications LED emphasized. Finally, prospects concerning development stable nanocrystals‐based future proposed.

Language: Английский

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Tuning luminescence from NIR-I to NIR-II in Cr³⁺-doped olivine phosphors for nondestructive analysis

Journal of Materials Chemistry C, Journal Year: 2021, Volume and Issue: 9(16), P. 5469 - 5477

Published: Jan. 1, 2021

We report a series of Cr³⁺-doped olivine phosphors with tunable luminescence from 940 to 1100 nm. They have promising applications in the field food processing for both qualitative identification and quantitative analysis.

Language: Английский

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