Realization and optimization of bismuth-activated Ba3Ga2O5Cl2 yellow phosphor for high-quality white LEDs

Chemical Engineering Journal, Год журнала: 2024, Номер 484, С. 149723 - 149723

Опубликована: Фев. 15, 2024

Язык: Английский

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Developing the Na₂CaZr₂Ge₃O₁₂:Cr³⁺ Garnet Phosphor for Advanced NIR pc-LEDs in Night Vision and Bioimaging

Chemistry of Materials, Год журнала: 2024, Номер 36(9), С. 4654 - 4663

Опубликована: Май 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

Язык: Английский

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Multiple Defect‐Induced High‐Resolution Near‐Infrared Mechanoluminescent Materials for Non‐Destructive Detection of Blood Glucose and Lipids

Advanced Materials, Год журнала: 2024, Номер 36(50)

Опубликована: Ноя. 6, 2024

Mechanoluminescence (ML) materials, known for their ability to convert mechanical energy into light, are increasingly recognized potential applications, such as in intelligent stress sensing, vivo bioimaging, and non-destructive monitoring. However, the low signal-to-noise ratio (SNR) narrow-band emission of single-defect-induced ML materials usually limit biological-related practical applications. Here, these limitations will be addressed by modulating microstructure evolution Y

Язык: Английский

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Constructing Broadband Near‐Infrared Garnet Emitters CaGd₂Ga₄SiO₁₂:Cr³⁺ with Unity Quantum Efficiency and High Thermal Stability for Versatile Applications

Small, Год журнала: 2025, Номер unknown

Опубликована: Фев. 4, 2025

Abstract The pursuit of broadband near‐infrared (NIR) phosphors for next‐generation smart NIR light sources has garnered extensive interest. However, developing efficiently excitable by blue to produce thermally stable and highly efficient emission surpassing 830 nm remains a formidable challenge. Herein, novel CaGd 2 Ga 4 SiO 12 garnet is reported, designed through structure reconstruction approach host Cr 3+ ions high‐performance phosphor. By strategically introducing Jahn–Teller distortion at the octahedral sites via chemical pressure, endowed with super‐broadband spanning 600–1300 centered 837 nm. full‐width half maximum (FWHM) varies from 187 223 across doping concentrations, highest internal quantum efficiency (IQE) 99.01%. Remarkable luminescence thermal stability (90.37%@423 K) bolstered weak electron‐phonon coupling (EPC) effect trap‐mediated energy compensation, result heterovalent ion substitutions in dodecahedral tetrahedral sites. Furthermore, prototype phosphor‐converted light‐emitting diode (pc‐LED) fabricated, delivering substantial output power 287.7 mW 1100 mA conversion (PCE) 24.4% 30 mA, enabling impressive performance versatile applications, including component analysis, non‐destructive testing, imaging, night vision.

Язык: Английский

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Enhanced Near-Infrared Luminescence and Thermal Stability in Cr3+-Activated Y2CaAl4SiO12 Phosphors: Towards High-Performance NIR Light Sources

Ceramics International, Год журнала: 2025, Номер unknown

Опубликована: Янв. 1, 2025

Язык: Английский

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

Inorganic Chemistry, Год журнала: 2023, Номер 62(27), С. 10772 - 10779

Опубликована: Июнь 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.

Язык: Английский

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Efficient and stable near-infrared Y₂Mg₂Al₂Si₂O₁₂:Cr³⁺ phosphor: analysis of the luminescence source by a site elimination strategy

Journal of Materials Chemistry C, Год журнала: 2024, Номер 12(8), С. 2814 - 2823

Опубликована: Янв. 1, 2024

The double luminescence centers of the Y 2 Mg Al Si O 12 :Cr 3+ phosphor are accurately analyzed by a site elimination strategy.

Язык: Английский

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Awakening the Dumb Site to Realize Ultra‐Broadband NIR Phosphor

Laser & Photonics Review, Год журнала: 2024, Номер 18(5)

Опубликована: Янв. 8, 2024

Abstract Near‐infrared (NIR) light sources have gained immense popularity in recent years due to their wide range of applications various fields, including spectroscopy and biomedical imaging. However, the limited emission bandwidth NIR phosphors is a significant bottleneck development. Here, novel strategy reported broaden by awakening dumb site. Na 4 M 3 Ta(PO ) 6 : Cr 3+ ( = Al , Ga In phosphor synthesized, which exhibits greatly broadened from 134 232 nm. Structural spectral analysis reveals that NaO octahedral site has severe t 2g ‐type distortion, making it for . By introducing larger at site, angular distortion decreases normal range, enabling luminescence again. Along with bandwidth, peak also redshifts 802 977 nm, giving advantages applications. Interestingly, awakened shows even better properties than original M/TaO These findings reveal insight into could potentially revolutionize design phosphors.

Язык: Английский

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Directly Identifying Multiple Cr³⁺ Emitting Centers for Broad Near‐Infrared Emission in an Efficient and Near‐Zero Thermal Quenching Garnet‐Type Phosphor

Advanced Optical Materials, Год журнала: 2024, Номер 12(11)

Опубликована: Фев. 8, 2024

Abstract Cr 3+ doped garnet‐type (A 3 B 2 C O 12 ) near‐infrared (NIR) phosphors is a desirable research hotspot due to their prospective night vision, bioimaging, and plant growth utilizations. Meanwhile, the origin of multisite broad emission yet controversial topic. To resolve trouble, verifying accurately multiple occupancy sites key. Furthermore, it an urgent need for improving external quantum efficiency luminescent thermostability. Herein, in Y Sc Al (YSAO), advanced electron microscopy technique employed directly confirm that obtained broadband NIR originates from [ScO 6 ] octahedral [YO 8 dodecahedral sites. The optimal YSAO:5%Cr sample exhibits high (IQE/EQE = 74/31%) near‐zero thermal quenching (97%@423 K 92%@473 K). theoretical calculations experimental proofs reveal YSAO possesses structural rigidity wide bandgap, which responsible extremely thermostable luminescence. high‐power ‐converted LED device shows promising multifunctional applications. This work not only provides efficient phosphor with quenching, but also effective determination method emitting centers materials.

Язык: Английский

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Preparation of (Lu,Y) ₃(Al,Sc,Cr) ₂Al ₃O ₁₂ phosphor ceramics with high thermal stability for near-infrared LED/LD

Journal of Advanced Ceramics, Год журнала: 2024, Номер 13(3), С. 354 - 363

Опубликована: Янв. 29, 2024

Near-infrared (NIR) phosphor-converted light-emitting diodes/laser diodes (LEDs/LDs) are prospective lighting sources for NIR spectroscopy. However, developing a phosphor material with desired thermal robustness and high photoelectric efficiency is crucial challenge its applications. In this work, based on the cationic radius matching effect, series of (Lu,Y)₃(Al,Sc,Cr)₂Al₃O₁₂ ceramics (LuYScCr NIR-PCs) were fabricated via vacuum sintering. An excellent stability (95%@150 ^oC) was obtained in prepared NIR-PC, owing to weak electron phonon coupling effect (small Huang Rhys factor). Being excited at 460 nm, NIR-PCs realized broadband emission (650-850 nm) an IQE 60.68 %. Combining LED/LD chips, maximum output power encapsulated LED prototype 447 mW @ 300 mA as 18.6 % 180 mA, LD 814mW 2.5 A. The working temperatures 70.8 ^oC (LED) 102.8 3 A (LD), respectively. Finally, applied food detection verified study, demonstrating anticipated application prospects future.

Язык: Английский

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