Valence conversion and site reconstruction in near-infrared-emitting chromium-activated garnet for simultaneous enhancement of quantum efficiency and thermal stability

Light Science & Applications, Journal Year: 2023, Volume and Issue: 12(1)

Published: Oct. 7, 2023

Achievement of high photoluminescence quantum efficiency and thermal stability is challenging for near-infrared (NIR)-emitting phosphors. Here, we designed a "kill two birds with one stone" strategy to simultaneously improve the NIR-emitting Ca3Y2-2x(ZnZr)xGe3O12:Cr garnet system by chemical unit cosubstitution, revealed universal structure-property relationship luminescence optimization mechanism. The cosubstitution [Zn2+-Zr4+] [Y3+-Y3+] played critical role as reductant promote valence transformation from Cr4+ Cr3+, resulting reconstruction octahedral sites Cr3+. introduction also contributed rigid crystal structure. These aspects together realized internal 96% excellent 89%@423 K. Moreover, information encryption "burning after reading" was achieved based on different resistance phosphors acid. developed phosphor-converted light-emitting diode demonstrated promising applications in bio-tissue imaging night vision. This work provides new perspective developing high-performance phosphor materials.

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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Blueshift and Photoluminescence Enhancement in Broadband Near‐Infrared Emitting Phosphor NaSr₂(Al/Ga)Ge₅O₁₄: Cr³⁺ Dependence on the Sc/In Substitution

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: 12(13)

Published: Jan. 26, 2024

Abstract Cr 3+ ‐activated near‐infrared (NIR) phosphors have gained extensive attention for use in NIR phosphor‐converted light‐emitting diodes (pc‐LEDs), which are required smart spectroscopy techniques. Nevertheless, obtaining broadband NIR‐emitting with outstanding thermal stabilities and photoluminescence (PL) efficiencies remains a significant challenge. Herein, considering NaSr 2 XGe 5 O 14 (X = Al, Ga, Sc, In) as hosts, possess large band gap multiple sites the substitution of ions. :Cr successfully prepared using solid‐state reaction technology. Upon blue light excitation, cover broad emission 650–1100 nm region. Notably, an abnormal blueshift PL enhancement observed following Al/Ga Sc/In. In particular, internal quantum efficiency is improved from 34.5% (NaSr GaGe : ) to 87.5% ScGe ). Moreover, manufactured pc‐LED exhibited exceptional photoelectric 17.7% output power 10.2 mW at 20 mA, its potential application nondestructive detection demonstrated.

Language: Английский

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Near-Infrared LuCa₂ScZrGa₂GeO₁₂:Cr³⁺ Garnet Phosphor with Ultra-broadband Emission for NIR LED Applications

Inorganic Chemistry, Journal Year: 2023, Volume and Issue: 62(27), P. 10772 - 10779

Published: June 27, 2023

Near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs), as a new generation of NIR lighting sources, have wide prospects in the areas food analysis and biological night vision imaging. Nevertheless, phosphors are still limited by short-wave narrowband emissions well low efficiency. Herein, series phosphors, LuCa2ScZrGa2GeO12:Cr3+ (LCSZGG:Cr3+), with broadband been developed first reported. At 456 nm excitation, optimized LCSZGG:0.005Cr3+ phosphor represents an ultra-broadband emission within range 650–1100 nm, peaking near 815 full width at half maximum 166 nm. Furthermore, possesses good internal quantum efficiency 68.75%, its integrated intensity 423 K retains about 64.17% that room temperature. By combining sample blue chip, pc-LED device is fabricated, which has excellent output power 37.88 mW photoelectric conversion 12.44% under 100 mA driving current. The aforementioned results demonstrate these LCSZGG:Cr3+ expected light sources.

Language: Английский

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Broadband near-infrared double-perovskite phosphor Sr2ScTaO6:Cr3+, Yb3+ for NIR pc-LED applications

Ceramics International, Journal Year: 2023, Volume and Issue: 49(20), P. 32860 - 32867

Published: Aug. 2, 2023

Language: Английский

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Highly thermally stable SrLaMgTaO6: Cr3+ double-perovskite phosphors for night-vision applications

Ceramics International, Journal Year: 2024, Volume and Issue: 50(16), P. 28707 - 28714

Published: May 12, 2024

Language: Английский

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Near-infrared luminescent materials: a review of their practical applications and prospective advancements

Dalton Transactions, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 1, 2025

This review covers NIR luminescent materials doped with RE, TM, and main-group ions, focusing on their optical properties, mechanisms, applications in bioimaging, LEDs, sensors, strategies to improve efficiency thermal stability.

Language: Английский

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Understanding the broadband near-infrared luminescence in a highly distorted garnet Ca₄HfGe₃O₁₂:Cr³⁺ phosphor

Physical Chemistry Chemical Physics, Journal Year: 2023, Volume and Issue: 25(22), P. 15452 - 15462

Published: Jan. 1, 2023

Broadband near-infrared (NIR) spectroscopy generated from a phosphor-converted light-emitting diode (pc-LED) has multifunctional applications, including food-quality analysis, bio-medical and night-vision, stimulating the demand for developing various NIR phosphors with desired properties. Herein, we selected highly distorted garnet Ca4HfGe3O12 as host explored luminescence of Cr3+. As expected, this material achieved long-wavelength emission excellent absorption efficiency based on effect Jahn-Teller distortion. The synthesized Ca4HfGe3O12:Cr3+ phosphor exhibits broadband peaking at 840 nm full width half maximum 150 nm, reaches 48.0%. However, internal quantum 6 mol% Cr3+-doped sample was measured to be only 35.3% integral intensity 373 K kept 60.1% initial intensity. possible reasons unsatisfactory thermal stability were systematically analyzed, which provided comprehensive understanding relationship between crystal structure luminescent properties Cr3+-activated garnet-type phosphors. Nevertheless, as-prepared pc-LED device output 16.52 mW photoelectric conversion 5.92% driven by 100 mA current, indicating potential application in pc-LED.

Language: Английский

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NIR-induced photothermal-responsive shape memory polyurethane for versatile smart material applications

RSC Advances, Journal Year: 2024, Volume and Issue: 14(33), P. 24265 - 24286

Published: Jan. 1, 2024

A review of recent advances NIR-light induced photothermal-responsive shape memory polyurethane for industrial and medical applications. It covers the classes photothermal agents, responsive mechanism, synthesis, advantages, challenges.

Language: Английский

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Tunable Luminescence in LiSc_1‐yGa_yW₂O₈:Cr³⁺ Phosphors for LED Applications

Advanced Optical Materials, Journal Year: 2024, Volume and Issue: unknown

Published: Sept. 14, 2024

Abstract Achieving emission peaks in the near‐infrared II regions (NIR II) and tunable (NIR) is still a huge challenge development of NIR phosphors. Here, series LiSc 1‐y Ga y W 2 O 8 :Cr 3+ phosphors are reported based on crystal engineering, whose luminescence can be tuned from NIR‐II to I. LiScW possesses an ultra‐wide range 850–1400 nm with peak at 1069 full width half maximum (FWHM) 225 main light located region. Introducing into form , spectrum blueshifted, which better aligns characteristic absorption lines most functional groups. Additionally, intensity thermal stability also improved. The phosphor‐converted light‐emitting diodes (pc‐LED) device prepared by using optimized 0.5 :0.12Cr phosphor green chip, different absorptions detected measuring water ethanol pc‐LED as radiation source. These results indicate that :xCr holds potential for applications non‐destructive analysis.

Language: Английский

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