Strategies to approach high performance in Cr3+-doped phosphors for high-power NIR-LED light sources

Light Science & Applications, Journal Year: 2020, Volume and Issue: 9(1)

Published: May 15, 2020

Abstract Broadband near-infrared (NIR)-emitting phosphors are key for next-generation smart NIR light sources based on blue LEDs. To achieve excellent phosphors, we propose a strategy of enhancing the crystallinity, modifying micromorphology, and maintaining valence state Cr 3+ in Ca 3 Sc 2 Si O 12 garnet (CSSG). By adding fluxes sintering reducing atmosphere, internal quantum efficiency (IQE) is greatly enhanced to 92.3%. The optimized CSSG:6%Cr exhibits thermal stability. At 150 °C, 97.4% emission at room temperature can be maintained. fabricated NIR-LED device emits high optical power 109.9 mW 520 mA. performances both achieved phosphor almost best results until now. mechanism optimization investigated. An application source demonstrated.

Language: Английский

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Divalent europium-doped near-infrared-emitting phosphor for light-emitting diodes

Nature Communications, Journal Year: 2019, Volume and Issue: 10(1)

Published: Nov. 20, 2019

Abstract Near-infrared luminescent materials exhibit unique photophysical properties that make them crucial components in photonic, optoelectronic and biological applications. As broadband near infrared phosphors activated by transition metal elements are already widely reported, there is a challenge for next-generation discovery introducing rare earth activators with 4 f -5 d transition. Here, we report an unprecedented phosphor K 3 LuSi 2 O 7 :Eu 2+ gives emission band centered at 740 nm full-width half maximum of 160 upon 460 blue light excitation. Combined structural spectral characterizations reveal selective site occupation divalent europium LuO 6 K2O polyhedrons small coordination numbers, leading to the unexpected emission. The fabricated phosphor-converted light-emitting diodes have great potential as non-visible source. Our work provides design principle europium-doped inorganic solid-state could inspire future studies further explore near-infrared diodes.

Language: Английский

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Two-Site Occupation for Exploring Ultra-Broadband Near-Infrared Phosphor—Double-Perovskite La₂MgZrO₆:Cr³⁺

Chemistry of Materials, Journal Year: 2019, Volume and Issue: 31(14), P. 5245 - 5253

Published: June 28, 2019

The near-infrared phosphor-converted light-emitting diodes (NIR pc-LEDs) have great potential in food industry and medical fields. For applications based on NIR spectroscopy, the next generation of pc-LEDs is a high demand spectrum with much broader full width at half-maximum (fwhm), which triggers discovery novel broadband phosphors. In this work, Cr3+-doped La2MgZrO6 (LMZ) was successfully synthesized by conventional solid-state method reducing atmosphere, double-perovskite oxide LMZ two distorted octahedral sites finally led to an ultra-broadband Cr3+ emission centered 825 nm extremely large fwhm 210 internal quantum efficiency ∼58%. experimental data theoretical calculation confirmed that available different crystal field environments contributed emission. parameters, decay time, temperature-dependent photoluminescence properties were investigated discussed further understand luminescence LMZ:Cr. suitability title phosphor multifunctional demonstrated pumping it blue, green, and/or red LED chips.

Language: Английский

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Highly efficient and thermally stable Cr3+-activated silicate phosphors for broadband near-infrared LED applications

Chemical Engineering Journal, Journal Year: 2019, Volume and Issue: 383, P. 123108 - 123108

Published: Oct. 9, 2019

Language: Английский

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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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Sb³⁺‐Doping in Cesium Zinc Halides Single Crystals Enabling High‐Efficiency Near‐Infrared Emission

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(40)

Published: July 10, 2021

Abstract Luminescent metal halide materials with flexible crystallography/electronic structures and tunable emission have demonstrated broad application prospects in the visible light region. However, designing near‐infrared (NIR) light‐emitting halides remains a challenge. Here, an enlightening prototype is proposed to explore high‐efficiency broadband NIR systems by incorporating Sb 3+ into Cs 2 ZnCl 4 matrix. Combined experimental analysis density functional theory calculations reveal modified self‐trapped excitons model elaborate emission. The high photoluminescence quantum yield of 69.9% peaking at 745 nm large full width half maximum 175 nm, along excellent air/thermal stability, show unique advantages lead‐free :Sb as source. substitution Cl − Br further enables red‐shift peak from 823 nm. diode device based on demonstrates potential non‐visible source night vision. This study puts forward effective strategy design novel eco‐friendly emissive provides guidance for expanding scope luminescent halides.

Language: Английский

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Enhancing Near-Infrared Photoluminescence Intensity and Spectral Properties in Yb³⁺ Codoped LiScP₂O₇:Cr³⁺

Chemistry of Materials, Journal Year: 2020, Volume and Issue: 32(6), P. 2430 - 2439

Published: Feb. 27, 2020

Near-infrared (NIR) phosphors have received increasing attention for designing novel solid-state light sources with broadband NIR output. In this work, a phosphor LiScP2O7:Cr3+ (LSP:Cr3+) is developed the emissions (750–1100 nm) completely in spectral range. Under 470 nm excitation, LSP:0.06Cr3+ shows peaking at ∼880 nm, full width half maximum (FWHM) of ∼170 and an internal quantum yield (IQY) ∼38%. Moreover, photoluminescence (PL) improvements LSP:Cr3+ are achieved by Yb3+ codoping, leading to broadened FWHM (up ∼210 nm), increased IQY (ηmax = ∼74%), reduced thermal quenching. The energy transformation processes LSP:Cr3+,Yb3+ quantitatively analyzed on basis PL lifetime QY measurements, revealing that codoping principally originate from transfer Cr3+ more efficient thermally stable emitters. Finally, phosphor-converted light-emitting diodes (pc-LEDs) fabricated combining blue LED chips, giving output power ∼36 mW photoelectric efficiency ∼12% 100 mA drive current. results suggest investigated would be promising luminescent converters pc-LED applications.

Language: Английский

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Efficient Super Broadband NIR Ca₂LuZr₂Al₃O₁₂:Cr³⁺,Yb³⁺ Garnet Phosphor for pc‐LED Light Source toward NIR Spectroscopy Applications

Advanced Optical Materials, Journal Year: 2020, Volume and Issue: 8(6)

Published: Jan. 17, 2020

Abstract Super broadband near‐infrared (NIR) phosphor converted light‐emitting diodes (pc‐LEDs) are future light sources in NIR spectroscopy applications such as food testing. At present, a few blue LED excitable super phosphors (bandwidth > 300 nm) have been developed producing the output powers below 26 mW at 100 mA input current after packaging. Here, an efficient achieved by doping Yb 3+ is reported Ca 2 LuZr Al 3 O 12 :Cr (CLZA:Cr ) garnet previously. Benefited from superposition of Cr emission and highly excited energy transfer , codoped CLZA:Cr ,Yb shows bandwidth 320 nm internal quantum efficiency 77.2% both higher than that (150 69.1%) singly doped phosphor. The converts produced 41.8 current. pc‐LED source also well applied to transmission spectra measurement water. results indicate great potential applications.

Language: Английский

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An Ultraviolet–Visible and Near‐Infrared‐Responded Broadband NIR Phosphor and Its NIR Spectroscopy Application

Advanced Optical Materials, Journal Year: 2020, Volume and Issue: 8(8)

Published: Feb. 23, 2020

Abstract High‐radiance near‐infrared (NIR) phosphor‐converted light‐emitting diodes (pc‐LEDs) are demanded for wearable biosensing devices and the properties of these pc‐LEDs highly dependent on performance NIR phosphor. An ultraviolet–visible NIR‐responded broadband NaScGe 2 O 6 :Cr 3+ phosphor is reported. Under 490 nm excitation, shows broad emission band from 700 to 1250 nm, which covers first second windows. pc‐LED with radiant flux 12.07 mW@350 mA realized based 450 blue LED chip. The ability high‐power light penetrate human tissues observed successfully. Additionally, in , luminescence Cr under 808 laser excitation achieved time.

Language: Английский

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Simultaneous Broadening and Enhancement of Cr³⁺Photoluminescence in LiIn₂SbO₆by Chemical Unit Cosubstitution: Night‐Vision and Near‐Infrared Spectroscopy Detection Applications

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(26), P. 14644 - 14649

Published: April 6, 2021

Abstract Near‐infrared (NIR)‐emitting phosphor materials have been extensively developed for optoelectronic and biomedical applications. Although Cr 3+ ‐activated phosphors widely reported, it is challenging to achieve ultra‐broad tunable NIR emission. Here, a new ultra‐broadband NIR‐emitting LiIn 2 SbO 6 :Cr with emission peak at 965 nm full‐width half maximum of 217 reported. Controllable tuning from 892 achieved by chemical unit cosubstitution [Zn 2+ –Zn ] [Li + –In ], which can be ascribed the upshift 4 T 2g energy level due strengthened crystal field. Moreover, greatly enhanced, FWHM reaches 235 nm. The as‐prepared luminescent demonstrated potential in night‐vision spectroscopy techniques. This work proves feasibility strategy ‐doped phosphors, stimulate further studies on emission‐tunable materials.

Language: Английский

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