Nanomaterials
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2019
·Vol. 9
·期 8
·1096
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IF 4.034
Liyuan Zhao,Renyan Zhang,Chuyun Deng,Yuanxi Peng,Tian Jiang
Controllably tuned infrared emissivity has attracted great interest for potential application in adaptive thermal camouflage. In this work, we report a flexible multilayer graphene based infrared device on a porous polyethylene membrane, where the infrared emissivity could be tuned by ionic liquid intercalation. The Fermi level of surface multilayer graphene shifts to a high energy level through ionic liquid intercalation, which blocks electronic transition below the Fermi level. Thus, the optical absorptivity/emissivity of graphene could be controlled by intercalation. Experimentally, the infrared emissivity of surface graphene was found to be tuned from 0.57 to 0.41 after ionic liquid intercalation. Meanwhile, the relative reflectivity Rv/R0of surface graphene increased from 1.0 to 1.15. The strong fluorescence background of Raman spectra, the upshift of the G peak (~23 cm−1), and the decrease of sheet resistance confirmed the successful intercalation of ionic liquid into the graphene layers. This intercalation control of the infrared emissivity of graphene in this work displays a new way of building an effective thermal camouflage system.Keywords:graphene;ionic liquid;intercalation;flexible;infrared emissivity
研究领域:
材料科学
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光学工程
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PubMed
高影响因子
Journal of Materials Chemistry B
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2016
·Vol. 4
·期 47
·7549-7559
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IF 4.872
Bao-xing Shen,Ying Qian
A novel triphenylamine-BODIPY based Schiff base fluorescent probe (TPA-BODIPY-OH) with an emission in the near-infrared (NIR) region was designed and prepared by click reaction. TPA-BODIPY-OH showed three emission bands at 510 nm, 598 nm and 670 nm, and can detect Fe3+ and Hg2+ ions with remarkable fluorescence enhancement in THF/H2O (v/v, 1 : 1, buffered with 10 mM HEPES pH = 7.4) based on the hydrolysis reaction of the –CN bond, and naked eye detection was realized with an obvious color change. The stoichiometry between the probe and ions was deduced from a Job's plot, which is 1 : 3 for TPA-BODIPY-OH/Fe3+ and 1 : 2 for TPA-BODIPY-OH/Hg2+, respectively. The dissociation constant value was found to be 1.35 × 10−16 M for TPA-BODIPY-OH/Fe3+ and 2.06 × 10−11 M for TPA-BODIPY-OH/Hg2+. The low detection limit was calculated from the titration results with the values of 5.15 × 10−7 M for TPA-BODIPY-OH/Fe3+ and 6.81 × 10−7 M for TPA-BODIPY-OH/Hg2+, respectively. In order to investigate the biological applications of TPA-BODIPY-OH, a living cell imaging experiment was carried out. The results demonstrate that TPA-BODIPY-OH can be successfully applied as a bioimaging agent in living cells. In addition, amino-group-functionalized silica fluorescent nanoparticles (FNPs) encapsulating the TPA-BODIPY-OH dyes were prepared and characterized by transmission electron microscopy. TPA-BODIPY-OH/SiO2 nanoparticles exhibit good dispersibility, and the quantum yield of FNPs at 657 nm was 42.3%.
研究领域:
化学
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生物成像
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材料科学
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PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2022
·
IF 6.371
Jiayu Liao,Peixiong Zhang,Xiaochen Niu,Hong Hong,Hao Yin,Zhen Li,Yin Hang,Zhenqiang Chen
A 2 BB’ X 6 double perovskite has recently been considered as a potential substitute for lead-based halide perovskite . In particular, the lead-free Cs 2 AgInCl 6 material possesses excellent moisture and thermal stability. However, the wide bandgap of the Cs 2 AgInCl 6 host limits its optical properties . Doping with active elements is a unique avenue to endow Cs 2 AgInCl 6 with excellent optical properties . Here, a strategy is proposed to explore the efficiency of near-infrared (NIR) emissions in Ln 3+ (Ln Nd, Yb) ions doped Cs 2 AgInCl 6 microcrystal by the codoping of Sb 3+ ion for the first time. The incorporation of Sb 3+ ion emerges a new optical absorption channel at a longer wavelength (>350 nm) and reduces the electron bandgap. Under the excitation at 365 nm, Sb 3+ and Ln 3+ (Ln Nd, Yb) co-doped Cs 2 AgInCl 6 show the efficient NIR emission peaking at around 1000 nm, attributing to the effective energy transfer from Sb 3+ to Yb 3+ or Nd 3+ f-electrons. Accordingly, the photoluminescence mechanism and environmental stability of Sb 3+ and Ln 3+ (Ln Nd, Yb) co-doped Cs 2 AgInCl 6 microcrystal were also discussed in detail. This work demonstrates the availability of the Sb 3+ doping tactics to realize efficient NIR emission in Ln 3+ (Ln Nd, Yb) doped Cs 2 AgInCl 6 microcrystal.
研究领域:
材料科学
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光学
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DOI
高影响因子
MODERN PHYSICS LETTERS B
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2024
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IF 1.8
Jiaqi Li,Jianyu Li,Bin Xu,Zhiyi Ren,Shixiao Yan,Di Zhang,Meng Wang,Xiaoliang Sun,Chi Liu,Jing Feng
This work aims to investigate the influence of Ca 2 + doping on the infrared emission properties of DyTa 3 O 9 ceramics. DyTa 3 O 9 is considered a promising high-temperature thermal protection material due to its low thermal conductivity and good high-temperature stability. However, there is currently no research on the infrared radiation performance of such materials. We synthesized DyTa 3 O 9 ceramics with different Ca 2 + doping concentrations using the solid-phase reaction method and systematically investigated the effect of doping concentration on the infrared emissivity of DyTa 3 O 9 ceramics. When Ca 2 + is doped into the DyTa 3 O 9 lattice, the original Dy elements are replaced by Ca, resulting in an increase in lattice constants and enhanced lattice distortion. The doping of Ca 2 + introduces impurity energy levels, making it possible for some low-energy electron transitions, achieving an enhancement in infrared absorption and emission capabilities. When the Ca 2 + doping concentration reaches 7.5% mol, the average infrared emissivity in the 3–5 μ m and 8–12 μ m ranges are 0.85 and 0.92, respectively, representing a 19.7% and 21% increase compared to DyTa 3 O 9 . This novel high-infrared-emissivity ceramic holds great potential for applications in high-temperature energy conservation and aerospace thermal protection.
研究领域:
材料科学
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陶瓷材料
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光学材料
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DOI
高影响因子
CERAMICS INTERNATIONAL
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2020
·
IF 3.83
Yunjia Hu,Tengchao Guo,Kangsen Peng,Shujuan Tan,Cheng Xu,Jie Deng
In this study, Ce 1−x Cu x O 2−x (x = 0, 0.01, 0.03, 0.05, 0.07) samples were prepared by hydrothermal method . The structure, microstructure, and elemental composition of the powders were characterized by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy, whereas the electrical conductivity , ultraviolet–visible absorption spectroscopy , and infrared emissivity at 3–5 μm were measured as well. Moreover, the effects of Cu 2+ doping concentration on the microstructure, morphology, bandgap, conductivity, and infrared emissivity of Cu-doped CeO 2 powders were systematically studied. The effects of Cu 2+ doping on infrared reflection and absorption in a 3–5 μm band and their mechanisms were explained based on electromagnetic theory, lattice vibration absorption, and free carrier absorption . Our result indicated that the emissivity of 1% Cu-doped powder reached the lowest emissivity of 0.200 at 800 °C. When the doping concentration was above 1%, the curve of infrared emissivity versus temperature exhibited a “U” shape, with the minimum point shifting towards the low-temperature region with the increase of Cu doping amount. This phenomenon was attributed to the different enhancement amplitude of reflectivity and absorbance of CeO 2 powder by Cu 2+ at different temperatures.
研究领域:
材料科学
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光学
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DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
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2019
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IF 4.175
Tengchao Guo,Guoyue Xu,Shujuan Tan,Zhihong Yang,Honghan Bu,Gang Fang,Haili Hou,Jing Li,Lingyu Pan
Nowadays, the high temperature low infrared emissivity problem has been of increasing significance and attracting more attention owing to the widespread applications for high temperature conditions. One key solution for this problem is to study the mechanism of high temperature low infrared emissivity and then design the materials with low infrared emissivity at elevated temperature. This paper gives an introduction to the infrared emissivity of ZnO powders in 3∼5 μm waveband at elevated temperature with various well-defined morphologies, e.g. needle-, pencil-, flower-, and flat-like. Among these morphologies, flat-like ZnO powders exhibit the lowest infrared emissivity because they have the largest real part of the dielectric function. Additionally, the variation of electrons average scattering time and lattice vibration at various temperature determine the variation tendency of infrared emissivity with temperature.
研究领域:
材料科学
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光学
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高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2016
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IF 4.758
Yan Zhang,Jingjing Jiang,Min Li,Pengfei Gao,Lihong Shi,Guomei Zhang,Chuan Dong,Shaomin Shuang
In this paper, we developed a simple one-pot method, employing inexpensive chicken egg white (EW) as a reducing/capping reagent, for microwave-assisted synthesis of water-soluble and well-dispersed chicken egg white-protected gold nanoclusters (EW@AuNCs) with far-red/near-infrared (FR/NIR) emission. The resultant AuNCs showed strong emission at 667 nm with a quantum yield of 7.23%. The excellent photostability, large Stokes shift (>350 nm), microsecond-scale lifetime and strong emission endowed EW@AuNCs potential as a sensing probe. The photoluminescence of EW@AuNCs could be quenched upon addition of either Hg 2+ or Cu 2+ ion. After ethylenediamine (En) was used as a masking agent, the EW@AuNCs offered highly selective for determination of Hg 2+ ion. Also, the resultant EW@AuNCs probe exhibited ultra-high sensitivity toward Hg 2+ ion with a detection limit as low as 20 pM, which is 500 times lower than the limit value (10 nM) defined by the U.S. Environmental Protection Agency in drinkable water. The proposed AuNCs probe for Hg 2+ ion has a linear range of 0.0446–5.90 nM and good repeatable response to 2.0 nM Hg 2+ with a relative standard deviation of 2.8% ( n = 5). Additionally, the applicability of the sensing system was also verified by analysis of Hg 2+ ion in tap water and pond water samples.
研究领域:
分析化学
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环境科学
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DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
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2017
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IF 1.753
Wenlu Pan,Yuming Zhou,Man He,Xiaohai Bu,Binbin Ding,Tingyuan Huang,Shuang Huang,Shiwei Li
Novel chiral N -propargylamide based on stigmasterol (M1, HC CCH 2 NHCOCH 2 CH 2 COO-R, R = stigmasteryl) and achiral N -propargylamide based on pivalic acid (M2) were prepared and (co)polymerized with rhodium zwitterions catalyst in CHCl 3 to afford helical polyacetylenes with moderate molecular weights (8997–26777) in good yields. The polymers were characterized by Fourier transform infrared spectroscopy (FT-IR), 1 H nuclear magnetic resonance ( 1 H NMR), gel permeation chromatography (GPC). Ultraviolet–visible spectroscopy (UV–Vis) and circular dichroism (CD) absorption spectra demonstrated that the as-prepared polymers could form helical structures with a preferential helicity. The formation of hydrogen bonds of poly(M1) in CHCl 3 was investigated according to the solution sate IR spectroscopic data . The single-handed helical conformation and polymerization degree of the new-typed poly( N -propargylamide)s could be controlled by the changing the feed ratio of chiral and achiral monomers . Furthermore, the infrared emissivity values (0.536–0.798) of copolymers were investigated at 8–14 μ m by the Infrared Emissometer.
研究领域:
高分子化学
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材料科学
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高影响因子
CHEMISTRY OF MATERIALS
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2020
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IF 9.567
Stephen V. Kershaw,Wai Kin Yiu,Aleksandr Sergeev,Andrey L. Rogach
Most successful syntheses of long-wavelength infrared (IR)-absorbing/emitting Hg-chalcogenide quantum dots (QDs) use either aqueous- or organic-solvent-based methods. Accounts of IR QD growth in aprotic solvents such as dimethyl sulfoxide (DMSO) or dimethylformamide (DMF) are much less common, and yet, producing QDs in such solvents can be useful from the perspective of further reactions to conjugate or incorporate the QDs with other materials since such solvents can be a useful meeting ground for both organic and ionic solutes. Here, we start by demonstrating long-wavelength infrared emission (across the wide spectral range of up to 4500 nm) in HgTe QDs grown in DMF under basic conditions. While many existing synthetic approaches use soluble chalcogen precursors in adduct, salt, or organo-chalcogenide forms, we have opted to take the approach of using slow addition of gaseous H2Te generated under programmed control, which allowed us to investigate the growth kinetics to manipulate the different competing processes and to obtain larger HgTe QDs with the best size distributions on a repeatable and controlled basis. We demonstrate how the nucleation process of HgTe QDs can be carried out analogously to the way that it occurs in classic hot injection syntheses but in our case at a far lower (subambient) temperature, owing to the use of a much more labile Te precursor. We also demonstrate the use of a two-stage, seeded QD growth process, which allows the synthesis conditions for the initial nucleation step and the subsequent enlargement stage to be decoupled; in other words, the QD concentration during the enlargement phase need not be forced to be excessively large by the choice of nucleation conditions. This approach should eventually be extendable to making >5000 nm emitting HgTe QD-based materials, and the use of aprotic solvents will offer compatibility with other nanomaterial chemistries, e.g., oxide glass formers, etc., for the synthesis of composites. By comparing the emission spectra of HgTe QDs grown in DMF with the spectra of those grown in DMSO, we show that polaron-mediated coupling to ligands and solvents, previously seen when using DMSO, can be substantially suppressed using our new synthetic method.
研究领域:
材料科学
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化学
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高影响因子
EUROPEAN JOURNAL OF INORGANIC CHEMISTRY
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2023
·Vol. 26
·期 35
·e202300556
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IF 2.3
Quwei Ni,Jiansheng Huo,Qijian Zhu,Jianbang Zhou,Wenjie Sun,Yutong Huang,Chenggang Long,Qianming Wang
Graphical The Ca3Sc2Ge3O12:Cr3+ NIR emission garnet phosphor exhibits broadband emission peaking at 817 nm with a FWHM value of 128 nm. The developed phosphor presents balanced comprehensive performance and is suitable for NIR-LED application. The rapid growth in phosphor-converted near-infrared light-emission diodes (NIR-LEDs) has led to the development of NIR emitter with high efficiency, broadband emission and high thermal stability. In this work, an efficient broad NIR emission of Cr 3+ in novel Ca 3 Sc 2 Ge 3 O 12 (CSGO) garnet-based host was developed for the first time, which located at 700 to 1000 nm peaking at 817 nm with a broad bandwidth of ~128 nm. Such a broadband NIR emission originated from the preferential occupancy of Cr 3+ in Sc 3+ sites with weak octahedral field, which was manifested by the luminescence spectrum and decay behaviors. The Cr 3+ -doping concentration was regulated to achieve a good internal quantum efficiency (IQE) of 72.1 % and a fantastic thermal stability (at 423 K, sustained approximately 85 % of the initial intensity). The mechanism for concentration and thermal quenching was further investigated. Benefiting from the excellent luminescence features, a prototype NIR-LEDs was assembled via integrating the optimized samples with commercial blue InGaN LED chips, which exhibited a satisfactory photoelectric property and a brilliant performance in night vision. These results demonstrated the as-obtained sample to be a great potential candidate for NIR-LEDs.
研究领域:
材料科学
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光学工程
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高影响因子
ACS Applied Materials & Interfaces
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2024
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IF 8.3
Yanshan Ju,Peng Yang,Jiajun He,Shaochun Tang
Radiative cooling fabrics have gained significant attention for their ability to enhance comfort without consuming extra energy. Nevertheless, sweat accumulation on the skin and diminishing cooling efficiency usually exist in the reported polymer cooling membranes. Herein, we report a universal method to obtain a calcium (Ca)-salt-enhanced fiber membrane with high infrared emission and hydrophilicity for efficient passive cooling and flame retardancy. The modification by Ca salts (including CaSiO3, CaSO3, and CaHPO4) with strong infrared emission results in an improvement in hygrothermal management ability, especially for moisture absorption and perspiration regulation in hot and humid environments. As an example, the CaSiO3@PMMA fiber membrane exhibits exceptional reflectivity in the solar spectrum (∼94.5%), high emittance in the atmospheric window (∼96.7%), and superhydrophilicity with a contact angle of 31°. Under direct sunlight, the CaSiO3@PMMA membrane exhibits an obvious temperature drop of 11.7 °C and moisture management achieves an additional cooling of 8.9 °C, as further confirmed by the ability to reduce the rate of ice melting. Additionally, the composite membrane provides notable flame retardancy and UV resistance. This work paves a new path in developing new materials with perspiration management and flame retardancy for zero energy consumption cooling in hot and humid environments.
研究领域:
材料科学
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能源工程
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纺织科学
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DOI
PubMed
高影响因子
Small Science
·
2025
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IF 8.3
Tianchi Wang,Jiabo Sun,Zhaowei Teng,Shuyi Yao,Junheng Yuan,Lulu Han,Dedan Mu,Hao Song,Xue Yu,Xuhui Xu
Bioimaging with remarkable noninvasive nature, ultrahigh resolution and sensitivity allows detection of pathologies of bones, organs, and tissues. Nevertheless, the achievement of more complete information in vivo is challenged by the necessity of multiple photodetectors with diverse response ranges. Herein, a multifunctional bioimaging with Cs 2 AgInCl 6 :Yb 3+ perovskites via a single InGaAs detector for superior tissue presentation is realized in this work. Co-incorporation of foreign dopant contributes to alterations of local structural symmetry of the Cs 2 AgInCl 6 host, disruption of parity-forbidden transitions, and reduction in electron–phonon coupling strength, thereby boosting the near-infrared (NIR) intensity by 40-fold of the corresponding perovskites drastically. Moreover, an X-ray excited NIR light output is 2.83 times that of commercial Bi 4 Ge 3 O 12 scintillators. Thanks to the efficient NIR emission, the versatile perovskites film endows a multifunctional bioimaging with detailed information of biological tissue in vivo, which fundamentally offers viable avenues for promoting bioimaging technology with integrated access of tissue presentation.
研究领域:
材料科学
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生物医学工程
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医学影像学
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DOI
PubMed
高影响因子