Materials Today Chemistry
·
2023
·
IF 7.3
Haonan Yu,Jingming Chan,Balaji Devakumar,Xiaoyong Huang
High-efficiency far-red emitting phosphors with an emission peak of around 730 nm are urgently needed for indoor plant growth light-emitting diode (LED) lighting. In this article, we report on the synthesis, crystal structure, and luminescence properties of a new highly efficient Mn 4+ ion-activated Li 3 La 3 W 2 O 12 (LLWO) far-red emitting phosphor. A group of LLWO:Mn 4+ phosphors doped with different Mn 4+ ion concentrations have been prepared via the conventional high-temperature solid-state reaction route. X-ray diffraction Rietveld refinement reveals that the LLWO:Mn 4+ phosphor has the monoclinic structure with space group P2 1 /n , along with lattice parameters of a = 5.5396 Å, b = 5.6026 Å, c = 7.8802 Å, α = γ = 90°, β = 90.0988°, and V = 244.57 Å 3 . Interestingly, LLWO:Mn 4+ phosphors can generate bright narrowband far-red emission in the 650–800 nm wavelength range peaking at 719 nm due to the spin- and parity-forbidden 2 E g → 4 A 2g transition of Mn 4+ ions, matching well with the absorption spectrum of phytochrome P FR . The excitation spectrum monitored at 719 nm has a broad excitation band with the range from 250 to 550 nm centered at 339 nm and 472 nm, indicating that LLWO:Mn 4+ phosphors could be efficiently pumped by both ultraviolet and blue LED chips. The highest far-red emission is achieved for the sample doped with 1.2 mol% Mn 4+ ion, and this optimal LLWO:1.2%Mn 4+ sample shows a high internal quantum efficiency of 88.4% and a decay lifetime of 2.289 ms. Commission Internationale de l’Eclairage (CIE) color coordinates of LLWO:1.2%Mn 4+ are determined to be (0.7326, 0.2674). Besides, the crystal field analysis and temperature-dependent emission spectra of the as-prepared samples have been investigated in detail. The emission intensity of LLWO:1.2%Mn 4+ sample at 423 K remains about 40% of that at 303 K. Finally, a LED device is fabricated by integrating the LLWO:1.2%Mn 4+ phosphors and a 460 nm blue LED chip, which shows bright blue and far-red dual emission bands under 20–300 mA driving currents. This work demonstrates that these newly developed far-red emitting LLWO:Mn 4+ phosphors have excellent application prospects in plant growth LED lighting.
研究领域:
材料科学
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园艺学
·
光学工程
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产品关联
DOI
高影响因子
DYES AND PIGMENTS
·
2025
·
IF 4.2
Jing Zhu,Songfang zhao,Ruifang Guan,Hao Zhang
Heteroatom doping can achieve specific regulation of carbon dots by changing their nanostructure, electronic structure and band gap. Here, we synthesized nitrogen-sulfur co-doped carbon dots (N, S-CDs) with full-spectrum fluorescence emission capability. Through comprehensive structural analysis using XPS, FTIR, and other characterization techniques, it was revealed that most of the nitrogen atoms were integrated into the carbon core of the N, S-CDs. Meanwhile, sulfur atoms were identified on the surface of the N, S-CDs, incorporated as functional groups. This unique structural configuration provides a foundation for understanding the solvent effect on N, S-CDs. Specifically, as the polarity of the solvent increases, the fluorescence emission of the N, S-CDs experiences a red-shift. The varying hydrogen donor abilities of different solvents contribute to changes in fluorescence emission. Notably, N, S-CDs exhibit near-infrared fluorescence emission when dissolved in acetic acid solvent. Under the synergistic effect of solvent polarity and hydrogen bonding, the fluorescence emission of N, S-CDs achieves full-spectrum luminescence, spanning from blue light to near-infrared. It is particularly interesting to observe that when N, S-CDs are dispersed in polyvinyl alcohol (PVA) films by dissolving them in three different solvents, the red, green, and yellow light emission can be achieved. When coated onto Light Emitting Diode (LED) lamp beads, these films exhibit versatile light emission properties. This provides inspiration for the development and preparation of LED fluorescent materials. Meanwhile, thanks to the excellent luminescent properties of N, S-CDs in water, they can be used for targeted localization of lysosomes in biological cells.
研究领域:
材料科学
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生物医学
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光学工程
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产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 36
·9454-9460
·
IF 4.696
Zhiyong Mao,Zhijuan Lu,Jingjing Chen,Bradley D. Fahlman,Dajian Wang
In this work, tunable luminescence of dicalcium silicate doped with Eu2+ ions is demonstrated based on crystal engineering. Five types of dicalcium silicate polymorphs (γ-, β-, αL′-, αH′-, α-Ca2SiO4) are synthesized by incorporating a crystal-phase stabilizer (CPS), in order to afford variable accommodation frameworks for the Eu2+ activator. Tunable luminescence is observed as the polymorph transforms from one crystal form into another. In addition, the luminescence of Eu2+ in peculiar crystal-phase Ca2SiO4 hosts is further customized by crystal-site engineering, which regulates the coordination environment of Eu2+ in multiple types of Ca2+ sites. The luminescence properties of our Eu2+-doped dicalcium silicate polymorphs show promising prospects for LED lighting applications.
研究领域:
材料科学
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光电子学
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晶体学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Inorganic and Organometallic Polymers and Materials
·
2018
·Vol. 28
·期 6
·2701-2713
·
IF 1.754
Wu Gang,Guo Shuang,Yin Yue,Sun Gang,Zhong Yongjian,You Bo
This paper presented a facile method to prepare the silica/poly (methyl methacrylate) (SiO 2 /PMMA) nanocomposite hollow microspheres (NHSs) which were firstly applied to fabricate the light diffusion films with high transmittance and high haze simultaneously. The SiO 2 /PMMA NHSs were prepared via in situ diffusion of polymeric core into the voids of inorganic shell under strong electrostatic attraction. The hollow morphologies of the microspheres were studied under the help of transmission electron microscope and scanning electronic microscope. The formation process of these NHSs could be elucidated using a mechanism similar to the Kirkendall effect. These NHSs were firstly used to produce light diffusion films by blending with polyacrylate latex. The new kind of light diffusion films with micro-nano structure were built by casting the SiO 2 /PMMA NHSs/polyacrylate coatings on optical-grade PET films. The transmittance and haze value of the light diffusion films were tested by a haze meter and application on a LED lamp. As a result, the coating films with NHSs had the best light diffusion properties compared to those films with no spheres or nanocomposite solid microspheres, which indicated that the light diffusion films with NHSs were promisingly applied in LED illumination, photoelectric devices and large area LCD.
研究领域:
材料科学
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Li Chen,Junting Chen,Chunyu Wang,MeiLing Chen,Fangyin Zhu,Zhengye Xiong,Jingyuan Guo
A dual-functional luminescent materials NaYSrWO 6 :xEu 3+ (x = 0.005,0.01,0.05,0.1,0.15,0.2,0.3,0.5) with a double perovskite structure was synthesized using a high temperature solid state reaction method. Systematic investigations of their photoluminescence, thermoluminescence and radiation luminescence properties were carried out. Under blue light excitation, Maximum PL intensity was achieved with Eu 3+ doping concentration of x = 0.15. Excited at 325 nm, the material exhibited characteristic red emission of Eu 3+ with quantum efficiency reaching 64.4 %, CIE color coordinates of (0.607, 0.358), color purity of 87.21 %, correlated color temperature of 1970 K, and activation energy of 0.214 eV. These parameters satisfy the critical requirements for phosphors in indoor LED lighting systems.The thermoluminescence curve of the sample shows two apparent peaks at approximately 407K and 460K temperatures.The material demonstrated superior thermoluminescence performance at doping concentrations (x = 0.3). TL response increased linearly with increase in dose rate within 0.266–2.1 Gy/min, indicating potential for real-time low-dose-rate radiation monitoring. After X-ray irradiation, it features fast saturation, stable luminescence, short afterglow, and excellent repeatability. This study confirms that the double perovskite tungstate NaYSrWO 6 :xEu 3+ simultaneously achieves efficient photoluminescence and radiation-responsive characteristics, demonstrating promising applications in white LED lighting, real-time dosimetry, and X-ray imaging technologies.
研究领域:
材料科学
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光学材料
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固态物理
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发光学
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辐射探测
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产品关联
DOI
高影响因子
Materials Advances
·
2021
·Vol. 2
·期 4
·1320-1327
·
IF 0
Yao Liu,Aifei Wang,Jiajing Wu,Chuying Wang,Ziliang Li,Guangcai Hu,Shiqi Sui,Jia-Xin She,Wen Meng,Weiqiang Li,Zhengtao Deng
In recent years, two-dimensional (2D) layered tin halide perovskites have attracted much attention due to their excellent luminescence properties compared with their three-dimensional (3D) analogs. Here, we synthesized 2D perovskites of the form (RNH3)2SnBr4 through a facile hot-injection approach without the use of toxic tri-n-octylphosphine (TOP) as the solvent. We found that these compounds have strong photoluminescence (PL) emission with high PL quantum yields (QY) of 35% ((C6H13NH3)2SnBr4), 82% ((C8H17NH3)2SnBr4), 60% ((C12H25NH3)2SnBr4) and 50% ((C18H35NH3)2SnBr4). Among them, ((C6H13NH3)2SnBr4) was synthesized for the first time; however, (C18H36NH3)2SnBr4 perovskites showed the best stability with a PL QY decrease of less than 1% after 30 days under ambient air and humidity conditions. In addition, other 2D (C8H17NH3)2SnX4 (X = Br, I, or mixture) perovskites were prepared by adjusting the halide ratio, resulting in spectral tunability from yellow to red. Interestingly, through Zn2+ doping, the morphology became more uniform, and the PL stability was significantly improved. Finally, we used Zn2+-doped (C8H17NH3)2SnBr4 yellow phosphor to fabricate UV-pumped yellow LEDs. We expect these 2D perovskites to be promising phosphors in future solid-state lighting and display technologies.
研究领域:
材料科学
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光电技术
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化学
✓ 已验证
产品关联
DOI
JOURNAL OF LUMINESCENCE
·
2022
·
IF 4.171
Lin Xiang,Xianju Zhou,Yongjie Wang,Li Li,Sha Jiang,Guotao Xiang,Chuan Jing,Jingfang Li,Lu Yao
Near infrared (NIR) light emitting phosphors have attracted more and more attention with the development of science and technology . Herein, we report a series of environmentally-friendly low-cost Fe 3+ -activated ZnGa 2 O 4 phosphors which exhibit intense broadband NIR light emitting. According to density functional theory (DFT) calculations, ZnGa 2 O 4 host possesses an indirect wide bandgap. The emission of the Fe 3+ -doped phosphors demonstrates a wide band spanning from 650 to 850 nm, with the maximum at 720 nm and a full width at half maxima (FWHM) of 70 nm, showing a large overlap with the absorption of phytochromes (PR and PFR). The luminescence intensity remains at 71% when the temperature is raised to 423 K. The phosphors are fabricated into light emitting diodes (LEDs) which produces strong NIR emission with CIE color coordinates of (0.65, 0.31). All these results suggest that ZnGa 2 O 4 :Fe 3+ is a promising NIR luminescent material , which is expected to be a candidate for indoor plant culture LEDs.
研究领域:
材料科学
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光电子学
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农业生物技术
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固体物理
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无机化学
✓ 已验证
DOI
高影响因子
JOURNAL OF BIOMEDICAL OPTICS
·
2025
·Vol. 30
·期 4
·046501
·
IF 2.9
Huaiyuan Zhang,Yiting Hu,Xingwei Pu,Shizheng Zhang,Yi He,Kun Chen,Ziji Liu
Significance The multiplexing capabilities of fluorescence imaging are enhanced by its exceptional molecular specificity with diverse fluorescent probes, making it a powerful tool for studying complex biological structures, organization, and functions. Recent advances in super-resolution fluorescence microscopy have further revolutionized our ability to explore biology and related fields. However, current multicolor super-resolution fluorescence imaging systems often come with high costs and bulky designs. Aim We present a multicolor extended resolution fluorescence imaging system that uses light-emitting diode to simplify the optical path, make the design more compact, and reduce system costs. Approach This multicolor extended resolution fluorescence imaging system is based on structured illumination, utilizing a simple diffraction unit positioned between the light source and the sample in a wide-field microscope. Notably, this design could be easily integrated into standard widefield microscopes as a convenient add-on unit, enabling extended resolution imaging. Results Our system demonstrates concurrent extended resolved imaging of three-color microsphere beads and successfully showcases multicolor extended resolution fluorescence imaging of biological tissue samples, revealing intricate structural details. Conclusions This system provides a structurally simple, cost-effective alternative to traditional microscopes, offering flexible multicolor extended resolution fluorescence imaging and potential applications in multimodal imaging.
✓ 已验证
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Jianyan Ding,Dewu Wu,Shanshan Ye,Quansheng Wu
The advancement of narrow-band cyan-emitting phosphors activated by near-ultraviolet LED chips is crucial for creating high-efficiency, health-promoting WLED lighting. Guided by a single and symmetrical crystallographic site, a near-ultraviolet excitation, near-narrow-band, and thermally stable cyan light emission was achieved from Bi 3+ -activated garnet-structured Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu). When incorporated into WLEDs, the color rendering index (CRI) of devices containing Ca 3 Sc 2 Ge 3 O 12 :Bi 3+ cyan phosphor reaches 92.8, indicating potential value for healthy lighting applications. Furthermore, by integrating spectral and crystallographic data with empirical formula calculations, a comprehensive analysis of the luminescence behavior among the three Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu) phosphors were performed. This analysis was designed to elucidate the similarities and differences in their luminescence properties, as well as to uncover the underlying mechanisms responsible for the near-narrow-band emission of Bi 3+ . The results indicate that under the combined influence of factors volume polarization, fractional covalency, and charge of the anions, Ca 3 Xn 2 Ge 3 O 12 :Bi 3+ (Xn = Sc, Y, Lu) exhibits the same strongest excitation peak. However, due to variations in Stokes shift and bandgap, the three phosphors exhibit distinct emission peaks and thermal quenching properties. This study aims to establish fundamental principles for the development of Bi³ ⁺-activated narrow-band emission phosphors.
研究领域:
材料科学
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光学材料
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固态照明
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无机化学
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晶体学
✓ 已验证
产品关联
DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2021
·
IF 5.268
Juan Zhao,Lixian Xu,Hao Zhang,Yuhong Zhuo,Yanan Weng,Shuang Li,Dinghua Yu
Recently, increased attention has been focused on antibacterial photodynamic therapy (APDT) to treat multidrug-resistant bacterial infection due to the antibiotic abuse. Methylene blue has been used as a kind of efficient and cheap commercial photosensitizer in APDT. However, due to high hydrophilicity, methylene blue is not able to be transcellular intaken and accumulated efficiently. To promote accumulation and APDT efficiency of methylene blue, lipopeptide surfactin-methylene blue complex has been prepared through electrostatic interaction. The complex under LED irradiation was found to effectively reduce 5.0 Log 10 CFU and 7.6 Log 10 CFU for P. aeruginosa and S. aureus , respectively. The bacterial reduction efficiency is slightly higher than free methylene blue. The photosensitizers accumulation and APDT targeting protein have been characterized by fluorescence spectroscopy, fluorescence microscopy and protein electrophoresis techniques. These results demonstrated that more surfactin-methylene blue complex could be accumulated more into the cell, and inactivate bacteria through destroying intracellular protein under LED illumination. In comparison, free methylene blue under light could inactivate bacteria through destroying membrane protein and lipid structures. These results would provide valuable insight for developing advanced clinical medicine and designing photo-drug for photodynamic therapy.
研究领域:
药学
·
微生物学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Wenjie Deng,Decai Huang,Fengli Yang,Jiaqing Peng,Weixiong You,Xinyu Ye
Efficient cyan-emitting phosphor plays an important role in the development of solid-state lighting, which is indispensable to filling the cyan gap for full-spectrum warm-white light-emitting diodes (WLEDs) with high color rendering index (CRI). Herein, a novel highly efficient broadband cyan phosphor Ce 3+ -doped Ca 3 HfAl 2 Si 2 O 12 (CHASO: Ce 3+ ) garnet compound was developed by the substitution of Lu 3+ -Al 3+ with Ca 2+ -Hf 4+ /Si 4+ in Lu 3 Al 5 O 12 . The crystal structure and photoluminescence (PL) properties of CHASO: Ce 3+ were investigated in detail. Notably, CHASO: Ce 3+ phosphor can be effectively excited by violet light (390 – 430 nm) and exhibited bright cyan emissions around 490 nm with high PL internal quantum yields of 89.2 %. Moreover, the integrated PL intensity of the phosphor at 423 K was 66.3 % of that at room temperature. Finally, by incorporating CHASO: 11 %Ce 3+ with commercial blue/yellow/red phosphor onto a violet LED chip (400 nm), the prototype full-spectrum WLEDs device exhibits warm white light with high color rendering index (CRI, Ra and R9 > 90) and low correlated color temperature 3301 K. These results suggest the highly efficient phosphor CHASO: Ce 3+ is promising for low-blue full-spectrum healthy lighting.
研究领域:
材料科学
·
光电技术
·
固态照明
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）