Nanomaterials
·
2019
·Vol. 9
·期 8
·1096
·
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
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MODERN PHYSICS LETTERS B
·
2024
·
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
·
陶瓷材料
·
光学材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
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
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2019
·
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
·
光学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR STRUCTURE
·
2017
·
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
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Yu Zhou,Jinxu Zhao,Xiansheng Li,Bin Zhao,Gang Pei,Jianming Zheng,Chunye Xu
Polyaniline (PANI) has the potential to control infrared emissivity but suffers from insufficient modulation. We mitigate this deficiency by employing metal compound doping to modify the structure and composition of PANI. The blackbody radiation-weighted emissivity modulation (Δε) in the 8–14 μm band increases from 0.055 without doping to 0.524 with manganese (Mn) doping. Thermal imaging confirms the remarkable infrared modulation of metal-doped PANI films. These results demonstrate the feasibility of using metal-doped PANI films for infrared thermal control applications and are expected to be used for innovations in smart thermal management.
研究领域:
材料科学
·
红外技术
·
智能材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Jinbu Su,Chenyi Shi,Chenzhuo Gong,Yuyi Xu,Yunong Xie,Xuli Lin,Xinyu Dong,Weixin Du,Yuchang Qing,Fa Luo
Semiconductor oxides are ideal candidates for future electromagnetic wave absorption and thermal management due to their hole-conducting properties. However, in practical applications, due to its limited conductivity, its development and application in the field of electromagnetic wave absorption and thermal management are greatly limited. The CuAl 1-x Fe x O 2 ceramics were synthesized using the high-temperature solid-phase method to study their microwave absorption and infrared emissivity characteristics. The introduction of Fe significantly improves the electromagnetic wave absorption and emissivity characteristics of CuAlO 2 ceramics. The effects of Fe doping on the dielectric constant, permeability, microstructure, and surface morphology of the composite were systematically analyzed. The results show that Fe doping leads to lattice distortion and the introduction of defects, which effectively improves the conductivity and polarization loss of the material, thus enhancing the dielectric loss and magnetic loss mechanisms of the material and obtaining excellent microwave absorption performance. The results show that when the doping amount of Fe is 3 %, the minimum reflection loss RLmin can reach −50.41 dB, and the effective absorption bandwidth EAB is 4.2 GHz. When the doping amount of Fe is 9 %, the infrared emissivity reaches a peak of 0.936. The porous structure further enhances the absorption and radiation properties of CuAl 1-x Fe x O 2 ceramics. It is further indicated that CuAl 1-x Fe x O 2 ceramics have great application potential in electromagnetic wave absorption and thermal management.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2012
·
IF 2.103
Yunxia Zhu,Yuming Zhou,Tao Zhang,Man He,Yongjuan Wang,Xiaoming Yang,Yong Yang
Lactate-intercalated Co–Fe layered double hydroxides (LDHs) were successfully prepared by coprecipitation and hydrothermal method. In this process, divalent metal ions as precursors can be obtained from the reduction reaction of lactic acid and metal powder (cobalt and ferrous). In order to obtain Fe 3+ , H 2 O 2 (30%) was used to oxidize Fe 2+ . Meanwhile, the produced lactate was intercalated into the LDHs interlayers to compensate the positively charged layers. The as-synthesized LDHs were studied by element chemical analysis, powder X-ray diffraction (XRD), FT-IR spectroscopy, thermogravitry (TG) and differential scanning calorimetry (DSC), TEM. The results indicated that the basal spacing value of the LDHs was larger than that of lactate-intercalated Mg–Al or Zn–Al LDHs. It proved that the lactate anions were inserted into the gallery in the form of dimers which made it easy to be delaminated in water. The obtained nanosheets were deposited on the substrates to form the film which was characterized by TEM and AFM, and infrared emissivity value (8–14 μm) was also investigated. The infrared emissivity values of Co–Fe LDHs were lower than that of Zn–Al which took advantage of the special electronic structure in Co and Fe. Besides, the orderly structure and the reduction of the interfacial deficiency of the film made the values further reduced.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
高影响因子
REACTIVE & FUNCTIONAL POLYMERS
·
2014
·
IF 2.822
Xiaohai Bu,Yuming Zhou,Zhenjie Chen,Man He,Tao Zhang
Chiral amino acid-based monosubstituted acetylene monomers [ N - tert -butoxy-carbonyl- l -phenylalanine- N ′-propargylamide (LP), and N - tert -butoxycarbonyl- l -serine- N ′-propargylamide (LS)] were (co)polymerized with rhodium zwitterion catalyst in THF to afford helical polyacetylenes (PAs) with moderate molecular weights (4400–14,800) in good yields. The optically active PA copolymers were soluble in common organic solvents and proven to adopt predominately single-handed helical conformations according to their intense Cotton effect and large specific rotations. Various contents of amino acid units in side chains facilitated controllable helical secondary structure while the helix was primarily stabilized by hydrogen bonding and steric repulsion between the substituents. Intramolecular hydrogen bonds constructed between hydroxyl and amide groups, in particular, played a significant role in adjusting the helicity and orderliness of the helix. The infrared emissivity values of the PAs at wavelength of 8–14 μm were measured and the correlation between helical conformations and their effect on infrared emission were systematically investigated. The results showed that more well-ordered and compact screw-sense could enhance the performance of organic polymers in lowering their infrared emissivity. Among all the as-prepared PAs, poly(LP 50 - co -LS 50 ) exhibited the lowest infrared emissivity value ( ε 25 = 0.632) and possessed excellent resistance against heat.
研究领域:
高分子化学
·
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Zekui Zhang,Leipeng Zhang,Zichen Ren,Yike Zhang,Tingting Hao,Dongqi Liu,Lei Xu,Wenchao Liu,Jiawu Sun,Haoyu Ji,Yuqiang Wang
The development of stealth devices that are compatible with both infrared (IR) and radar systems remains a significant challenge, as the material properties required for effective IR and radar stealth are often contradictory. In this work, based on an IR electrochromic device (IR-ECD), concepts of metamaterial manipulating electromagnetic waves are applied to develop a multifunctional ultrathin metasurface with a low radar cross section (RCS) and variable infrared emissivity. This paper presents a linear-to-linear polarization conversion metasurface (PCM) designed by hollowing the IR-ECD. In this way, the IR-ECD based on polyaniline (PANI) can also modulate the reflection waves in the microwave band without affecting its features in the infrared region. Thus, the proposed metasurface integrates both microwave stealth and variable infrared emissivity through a single layer. The measured results show that a 10 dB RCS reduction is achieved in the band of 8.46–9.5 GHz, and the infrared emissivity can be adjusted from 0.870 to 0.513 in the infrared stealth band of 8–14 μm. Due to the ultrathin thickness (only 0.081λ0 at 9 GHz), low RCS in the X-band, and variable infrared emissivity, the designed multifunctional stealth metasurface has promising applications on military platforms with various surrounding environments.
研究领域:
材料科学
·
电磁学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Jingxuan Cui,Jiao Wu,Aihu Feng,Yang Yu,Le Mi,Yun Yu
As a novel material with low infrared emissivity, Ti 3 C 2 T x MXene is promising in infrared stealth. However, the problem that MXene is easily oxidized poses a great challenge to its practical applications. In this paper, a tannic acid (TA) enhanced MXene oxidation stability composite film with low infrared emissivity is reported. TA effectively diminishes the pore size within the MXene film and leads to a tight and orderly arrangement of nanosheets, maintaining the low emissivity properties of Ti 3 C 2 T x MXene itself. In addition, TA reacts preferentially with H 2 O/O 2 entering the film to consume the oxidizing source, while also being able to form coordination with Ti atoms for protection against oxidation, resulting in the composite film exhibiting excellent oxidation resistance. Remarkably, there is no formation of TiO 2 and the emissivity only rises from 0.16 to 0.18 after 72 h in the humid heat environment. Even after prolonged exposure to 20-day humid heat, it still maintains exceptional infrared emissivity (0.24) and stealth performance (reducing the radiant temperature of the object from 94 °C to 47.4 °C, △T = 46.6 °C). In contrast, the original Ti 3 C 2 T x MXene film has lost its infrared stealth performance after 10-day humid heat (△T = 5.3 °C) with an infrared emissivity of 0.76. This paper provides a new strategy to solve the problem of MXene performance stability in humid and oxidizing environments.
研究领域:
材料科学
·
纳米技术
·
表面化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2014
·Vol. 132
·期 1
·
IF 1.64
Xiaohai Bu,Yuming Zhou,Tao Zhang,Man He,Yongjuan Wang
Serine-based monosubstituted acetylene monomers were synthesized and polymerized with rhodium zwitterion catalyst in THF to afford optically active polyacetylene derivatives (LPA and DPA) and corresponding racemic polyacetylenes (RPA) with moderate molecular weights in good yields. All of the substituted polyacetylenes (SPA) were characterized by FT-IR, NMR, GPC, UV-Vis spectroscopy, circular dichroism (CD) spectroscopy, and TGA. LPA and DPA were soluble in common organic solvents and possessed single-handed helical conformation according to their intense Cotton effect and large specific rotations, while RPA presented random coiled polymer chain. The characterization results showed that helical structure of these SPAs was stabilized by intra- and intermolecular hydrogen bonding between the substituents which played a significant role in creating and maintaining the helix. Further, the infrared emissivity properties of them at wavelength of 8 to 14 μm were investigated at room temperature. Consequently, the LPA and DPA exhibited lower infrared emissivity values than RPA, which came down to 0.632 and 0.616. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132 , 41210.
研究领域:
有机化学
·
材料科学
·
光谱学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）