Ab Initio Site‐Selective Occupancy and Luminescence Enhancement in Broadband NIR Emitting Phosphor Mg₇Ga₂GeO₁₂:Cr³⁺

Laser & Photonics Review, Journal Year: 2023, Volume and Issue: 17(7)

Published: March 15, 2023

Abstract Cr 3+ activated near‐infrared (NIR) phosphors are getting unprecedented attention to fabricate the broad band NIR light emitting diodes (NIR‐LEDs) for nondestructive detection, bio‐imaging, and night vision. However, it remains a major challenge obtain ultrabroadband phosphor with excellent quantum yield (QY). Here, broadband Mg 7 Ga 2 GeO 12 :Cr (MGGO: ) ranging from 600 1300 nm an outstanding QY (93%) large full width of half maximum (FWHM = 226 nm) is developed, in which site occupancy tendency MGGO host discussed detail through combining structure optimization first‐principles theory calculation luminescent properties at low temperature. After that, emission intensity MGGO:Cr improved partial substitution 2+ by alkaline‐earth ions Ca , Sr or Ba luminescence enhancement mechanism also investigated. Furthermore, pc‐LED device fabricated 450 blue LED chip brightest /Ba its potential applications evaluated field vision, bio‐imaging.

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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A broadband near-infrared nanoemitter powered by mechanical action

Matter, Journal Year: 2023, Volume and Issue: 6(9), P. 2935 - 2949

Published: July 5, 2023

Language: Английский

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Achieving broadband near-infrared luminescence in Cr3+-Activated Y2Mg2Al2Si2O12 phosphors via multi-site occupancy

Advanced Powder Materials, Journal Year: 2024, Volume and Issue: 3(3), P. 100186 - 100186

Published: March 6, 2024

Cr3+-activated near-infrared (NIR) phosphors are key for NIR phosphor-converted light emitting diodes (NIR pc-LED). While, the site occupancy of Cr3+ is one debates that have plagued researchers. Herein, Y2Mg2Al2Si2O12 (YMAS) with multiple cationic sites chosen as host to synthesize YMAS: xCr3+ phosphors. In YMAS, ions occupy simultaneously Al/SiO4 tetrahedral, Mg/AlO6 octahedral, and Y/MgO8 dodecahedral which form three luminescent centers named Cr1, Cr2, Cr3, respectively. Cr1 Cr2 relate an intermediate crystal field, transitions 2E→4A2 4T2→4A2 occurring simultaneously. As concentration increases, transition becomes more pronounced in resulting a red-shift broadband emission. Cr3 consistently behaves weak field exhibits broad long-wavelength Wide-range emission centering at 745 nm realized 0.03Cr3+ phosphor. This phosphor has high internal quantum efficiency (IQE = 86%) satisfying luminescence thermal stability (I423 K 70.2%). Using this phosphor, pc-LEDs 56.6 mW@320 mA optical output power packaged applied. Present study not only demonstrates multi-site certain oxide but also provides reliable approach via choosing diverse local environments achieve

Language: Английский

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High‐Efficiency Short‐Wave Infrared Emitter Enabled by Cr³⁺–Yb³⁺ Co‐Doped Phosphor

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(16)

Published: March 14, 2024

Abstract The utilization of phosphor‐converted light‐emitting diodes (pc‐LEDs) as compact short‐wave infrared (SWIR) emitters has emerged a promising strategy for miniature SWIR spectrometers in portable devices, enabling diverse applications such nondestructive identification, bioimaging, night‐vision surveillance, and optical communication. However, discovering phosphors capable efficiently absorbing blue light emitting pure (>900 nm) remains significant challenge. Here, highly efficient thermally stable luminescence Yb 3+ upon LED excitation by employing Cr –Yb energy transfer Y 3 Ga 5 O 12 garnet is reported. prepared :Cr ,Yb phosphor exhibits intense emission spanning from 900 to 1150 nm at 438 excitation, coupled with ultra‐high internal/external quantum efficiency 80.8%/40.2% excellent thermal stability (108%@150 °C). A pc‐LED prototype fabricated incorporating the optimized commercial 450 chip, shows exceptional performance, delivering output power 92.7 mW driving current 350 mA photoelectric 21.5% 10 mA. This work opens up new avenue designing that exhibit photoluminescence demonstrating potential next‐generation high‐power sources.

Language: Английский

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Ultra-broadband near-infrared Gd3MgScGa2SiO12: Cr, Yb phosphors: Photoluminescence properties and LED applications

Journal of Alloys and Compounds, Journal Year: 2022, Volume and Issue: 920, P. 165912 - 165912

Published: June 17, 2022

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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NIR Mechanoluminescence from Cr³⁺ Activated Y₃Al₅O₁₂ with Intense Zero Phonon line

Advanced Functional Materials, Journal Year: 2023, Volume and Issue: 33(27)

Published: May 1, 2023

Abstract Mechanoluminescence (ML) materials with long‐wavelength emission bands are essential for future in vivo bioimaging, non‐destructive testing of solids, etc. The lack a defined mechanism, however, prevents the application near infrared ML above 650 nm several new fields. Here, addition Ga 3+ ions to Y 3 Al 5 O 12 : Cr manipulates matrix microstructure evolution, boosting near‐infrared (NIR) zero‐phonon line (ZPL) stress optical output ion at 688 nm. key factor changing crystal field intensity D q /B due is what causes luminescence amplification ZPL. fabricated by composite polydimethylsiloxane and 4 GaO (YAGG: ) may penetrate chicken feet epidermal tissue mm pork thanks strong NIR ZPL YAGG: phosphor. This discovery enhancing solid solution provides us technique optimizing materials, as well prospect biological applications.

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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Eu³⁺‐Activated Single‐Band Ratiometric Nanothermometry by Lattice Negative Thermal Expansion

Laser & Photonics Review, Journal Year: 2023, Volume and Issue: 17(8)

Published: April 3, 2023

Abstract Single‐band ratiometric (SBR) thermometry has recently emerged as a powerful alternative to its dual‐emission counterparts because it can avoid the large uncertainties related emission spectral overlap or light absorption/scattering by medium. Herein, novel SBR thermometric scheme in Sc 2 Mo 3 O 12 :Eu 3+ nanosheet that depends on thermal enhancement of charge‐transfer state absorption between 2− and Eu is reported. Mechanistic investigation reveals vital role lattice negative expansion (NTE) for thermally enhanced emissions according configuration coordinate model. In contrast, serious quenching detected under excitation wavelength corresponding ground absorption. Such wavelength‐dependent behavior luminescence enabled with high sensitivity resolution ( S r = 2.0% K −1 , δT 0.121 at 363 K). Finally, applicability proposed model real‐world sensing scenarios demonstrated using as‐fabricated flexible thin‐film, offering accurate real‐time temperature detection local hotspot electronic component.

Language: Английский

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