Results in Physics
·
2019
·
IF 3.042
Dongyong Shan,Jun He,Lianwen Deng,Shuoqing Yan,Heng Luo,Shengxiang Huang,Yunchao Xu
Incorporation of magnetic loss component is more favorable to high-performance microwave absorbing materials. In this paper, the NiFe 2 O 4 -decorated Ti 3 C 2 T x MXene composites were synthesized by the in-situ chemical co-precipitation method. The magnetic NiFe 2 O 4 nanoparticles were attached on the surfaces or inserted into the interlayers of Ti 3 C 2 T x MXene. Interestingly, we reduced effectively complex permittivity and enhanced magnetic loss by increasing the NiFe 2 O 4 content on Ti 3 C 2 T x MXene. Stronger electromagnetic attenuation ability and preferable impedance matching property were achieved and considered to be responsible mainly for improving absorbing peaks as well as bandwidth of the NiFe 2 O 4 -Ti 3 C 2 T x MXene composite. In particular, the NiFe 2 O 4 -Ti 3 C 2 T x -20 sample exhibited an optimal effective absorption bandwidth ( RL < −10 dB) of 7.68 GHz with the material thickness of only 1.5 mm. These findings are believed to pave the way of further promoting microwave absorption performance of Ti 3 C 2 T x MXene from magnetic functionalized decoration of view.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MAGNETISM AND MAGNETIC MATERIALS
·
2015
·
IF 1.97
Pingyuan Meng,Kun Xiong,Kui Ju,Shengnan Li,Guangliang Xu
To achieve stronger microwave attenuation and larger bandwidth in electromagnetic absorber, the nickel ions (Ni 2+ ) and manganese ions (Mn 2+ ) were employed to partially replace the cobalt ions (Co 2+ ) in BaCoTiFe 10 O 19 , and the doped barium hexaferrite (Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 and Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 ) powders were synthesized via the sol–gel combustion method. Subsequently, the microwave absorbing composites were prepared by mixing the ferrite powders with the paraffin. The X-ray diffraction (XRD) patterns of the doped ferrites confirmed the formation of the M-type barium ferrite , and no other types of barium ferrite could be found. Based on the electromagnetic parameters measured by the vector net-analyzer, it was found that the composite (Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 ) possessed a minimum reflection loss of −52.8 dB at 13.4 GHz with a matching thickness of 1.8 mm and the bandwidth below −15 dB was 5.8 GHz. Moreover, the maximum attenuation of Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 could reach −69 dB when its thickness was 1.8 mm, and also the bandwidth less than −20 dB was ranging from 13.2 GHz to 18 GHz. Thus, Ba(MnNi) 0.2 Co 0.6 TiFe 10 O 19 and Ba(MnNi) 0.25 Co 0.5 TiFe 10 O 19 could be the good microwave absorbers, which have great potentials to be applied in the high frequency fields of the microwave absorbing materials.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 102
·100585-100589
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IF 3.289
Haibo Yang,Ning Han,Ying Lin,Ge Zhang,Lei Wang
Polyaniline/CoFe2O4/polyvinylidene fluoride (PANI/CoFe2O4/PVDF) composites were synthesized by an in situ polymerization method. The electromagnetic data demonstrate that the PANI/CoFe2O4/PVDF composite exhibit an excellent microwave absorption in the range of 2.0–18.0 GHz. The maximum reflection loss (RL) value can reach −57.7 dB at 7.6 GHz with a thickness of 4 mm and the absorption bandwidth with the RL below −10 dB is up to 3.4 GHz (from 6.5 to 9.9 GHz), which indicates that the microwave absorbing properties of the PANI/CoFe2O4 composite can be enhanced by the introduction of PVDF and the PANI/CoFe2O4/PVDF composite has potential applications for high-efficient microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2020
·
IF 2.029
Ying Zhai,Dongmei Zhu,Qiang Chen,Hanyi Nan
Herein, we report a novel multi-component electromagnetic microwave absorber with oriented flaky carbonyl iron&MoS 2 (FCI&MoS 2 ) as fillers and polyurethane (PU) as matrix. The SEM and VNA were utilized to analyze the morphology, electromagnetic and microwave absorption properties of the prepared oriented FCI&MoS 2 /PU composites with different multi-component proportions. The reflection loss (RL) and Z in /Z 0 values are calculated based on the complex permittivity and permeability. The results demonstrate that the oriented arrangement, synergistic effect and appropriate proportion of FCI&MoS 2 fillers are contributed to improve the impedance matching and microwave attenuation of the prepared composites at thin thicknesses of 0.8 mm and 0.9 mm.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2022
·Vol. 15
·期 9
·3408
·
IF 3.748
Leilei Zhang,Yihua Lv,Xiaoyun Ye,Lian Ma,Song Chen,Yuping Wu,Qianting Wang
In this study, zinc oxide (ZnO)/polypyrrole (PPy) composites with flower- and rod-like structures were successfully fabricated by in situ polymerization and the hydrothermal method and used as microwave absorption (MWA) materials. The surface morphologies, crystal structures, and electromagnetic features of the as-prepared samples were measured by field-emission scanning electron microscopy (FE-SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), and vector network analyzer (VNA). The results show that the conductive polymer PPy was successfully decorated on the surface of ZnO substrates. The MWA ability of flower- and rod-like ZnO/PPy composites is significantly enhanced after introduction of PPy. Rod-like ZnO/PPy composites exhibited superior MWA properties than those of flower-like ZnO/PPy. The former achieved a minimum reflection loss (RLmin) of −59.7 dB at 15.8 GHz with a thickness of 2.7 mm, and the effective absorption bandwidth (EAB,RL< −10 dB) covered 6.4 GHz. PPy addition and stacked structure of rod-like ZnO/PPy composites can effectively improve the dielectric properties, form multiple reflections of incident electromagnetic waves, and generate an interfacial polarization effect, resulting in improved MWA properties of composite materials.Keywords:ZnO;polypyrrole;composites;microwave absorption;dielectric loss
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Small Science
·
2022
·Vol. 2
·期 7
·2200018
·
IF 0
Yajun Zhang,Long Pan,Peigen Zhang,ZhengMing Sun
High-performance electromagnetic (EM) absorbing materials are in urgent need due to severe EM pollution caused by fast development of communication technology and electronic devices. Gradient structure benefits EM absorbing performance. However, the relevant study is very limited, and the relationship between component layers and overall performance is unclear. Herein, a gradient structure containing impedance matching layer, lossy layer, and reflective layer is built via repeated casting-drying method using Ti 3 C 2 T x MXene and polyvinyl alcohol. With optimized gradient structure, the minimum reflection loss (RL) reaches −74.8 dB with effective absorbing bandwidth (EAB) covering the whole X-band. The good absorbing performance is ascribed to the good impedance matching, which is derived from the stepwisely increased permittivity of each layer. Moreover, it is found that RL reaches the lowest value when lossy layer permittivity is close to the average permittivity of impedance matching layer and reflective layer. In addition, the decrease of lossy layer permittivity causes the decrease of total thickness of the gradient structure. This work demonstrates the effectiveness of gradient structure toward strong and broadband microwave absorption and provides rules for designing proper gradient structures to satisfy different requirements.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
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2022
·Vol. 33
·期 13
·9830-9844
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IF 2.779
Liu Gu,Wang Weichao,Wang Liuying,Ge Chaoqun,Wang Wenhao,Wang Long,Xu Kejun,Chen Mengzhou
La 0.8 Sr 0.2 MnO 3 (LSMO) powder was prepared using the sol–gel method and treated at different annealing temperatures ( AT ), and the effects of AT on the crystal structure, oxygen vacancies, magnetic, electromagnetic, and microwave absorption properties of LSMO were investigated. Our results showed that with increased AT , the lattice constant and average grain size increased while the density of oxygen vacancies gradually decreased. The bond angle of Mn–O–Mn and saturation magnetization also increased gradually when AT ≤ 1373 K, and decreased slightly when AT = 1473 K. The increase of mole ratio of Mn 4+ and grain size growth also contributed to the significant improvement in electrical conductivity of LSMO, while the decreases polarization of the material weakened its dielectric properties. When the frequency range was 2–18 GHz, and AT = 1173 K, LSMO exhibited the maximum effective bandwidth, which was 4.7 GHz (13.1–17.8 GHz) when the thickness was 1.62 mm. A minimum reflection loss ( RL ) of − 21.4 dB was reached at 15.8 GHz. Furthermore, when T = 973 K, LSMO exhibited excellent low-frequency absorption properties. When the thickness was 2.2 mm, the effective bandwidth in the X-band was 3.2 GHz (8.65–11.85 GHz) and RL was − 46.3 dB at 10.4 GHz. This indicated that the annealing temperature was the key parameter for determine the effective working frequency band of LSMO. As a result, this work provides a reference for regulating the electromagnetic properties of LSMO, which is necessary to meet the microwave absorption requirements in different occasions.
研究领域:
材料科学
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物理学
✓ 已验证
产品关联
DOI
高影响因子
Processes
·
2022
·Vol. 10
·期 4
·782
·
IF 3.352
Hui Wang,Bowen Zhang,Pan Luo,Kama Huang,Yanping Zhou
Here, FeAlOxcatalytic deconstruction of polyethylene in a domestic microwave oven is reported. With the starting weight ratio of FeAlOxto polyethylene at 1:1, the concentration and yield of H2reach up to 67.85 vol% and 48.1 mmol g−1plastic, respectively. CNTs@Fe3O4/Fe3C/Fe composite, which exhibits excellent microwave absorption properties, is generated simultaneously. The minimum reflection loss (RLmin) of the solid product reaches −54.78 dB at 15 GHz with an effective absorption bandwidth of 4.5 GHz at the thickness of 1.57 mm.Keywords:catalytic cracking;plastic waste;carbon nanotubes;hydrogen;microwave absorption
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Bo Dai,Yong Ma,Shixuan Feng,Haowen Wang,Mingliang Ma,Jianxu Ding,Xunqian Yin,Tingxi Li
The development of microwave absorbing materials with strong absorption capacity, wide bandwidth and light weight has always been a topic of concern. Herein, one-dimensional (1D) M (Co, Ni)@polyaniline (PANI) nanochains (NCs) with adjustable thickness have been successfully synthesized by reducing the mental ions under a parallel magnetic field, pretreating metal nanochains with KH550 and pre-oxidization of aniline monomer. It is found that Co has a more favorable absorption width for electromagnetic waves (EMW) and Ni aims at the absorption intensity. Furthermore, the effect of metal elements on adjusting impedance matching is more significant than their magnetic loss for composites. The minimum reflection loss (RLmin) of CoP2 can be up to −73.16 dB at 4.63 mm and the effective absorption bandwidth (EAB) is 4.98 GHz at 2.17 mm, while those of NiP2 are −65.06 dB at 3.88 mm and 5.02 GHz at 2.05 mm. The increase of PANI content can significantly reduce the matching thickness. And the RLmin of CoP3 and NiP3 can reach −58.72 dB at 2.32 mm and −65.96 dB at 1.59 mm, respectively. The absorption mechanism reveals that the matching thickness of the quarter-wavelength determines frequency location. And high absorption intensity is attributed to the synergistic effects of impedance matching, conduction loss, polarization loss, and magnetic loss. This work provides a theoretical basis for designing PANI or other conducting polymers coating magnetic nanochains for electromagnetic absorbing materials with strong absorption capacity, wide bandwidth and light weight.
研究领域:
材料科学
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电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Bingbing Fan,Muhammad Tamoor Ansar,Qianqian Chen,Fengchun Wei,Heng Du,Bo Ouyang,Erjun Kan,Yongqiang Chen,Biao Zhao,Rui Zhang
Simple and effective synthesis methods for 2D/2D heterostructure and the synergistic effect of 2D/2D composites on microwave absorbing (MWA) performance remain to be further explored and investigated. Herein, 2D/2D MoS 2 /Ti 3 C 2 T x heterostructure was successfully synthesized in 30 min by a cost-effective and time-saving microwave-assisted hydrothermal method . The 2 H-MoS 2 nanosheets with a thickness of 5–10 nm were homogeneously anchored on the surface of Ti 3 C 2 T x layers, showing a tunable distribution density. Besides, the metallic properties of MoS 2 /Ti 3 C 2 T x and the strong interaction between MoS 2 and Ti 3 C 2 T x , were revealed by DFT calculations, which was employed to further understand the MWA mechanism in terms of molecular dynamics. The MoS 2 /Ti 3 C 2 T x composites with an optimum mass ratio of MoS 2 to Ti 3 C 2 T x (6:1) displayed the best MWA performance. The minimum reflection loss ( RL ) value of −41.5 dB was attained with a layer thickness of only 2.0 mm at 12.2 GHz and a 3.6 GHz maximum efficacious absorption bandwidth. The MWA mechanism of MoS 2 /Ti 3 C 2 T x composites was comprehended from multiple reflections and scattering effects, synergetic effects of conductive losses and attenuation capacity, and polarization relaxations. This work provides a facile method for the synthesis of 2D/2D heterostructure, and also provides a candidate material as potential microwave absorber.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
·
2022
·Vol. 24
·期 1
·504
·
IF 6.208
Zhilan Du,Dashuang Wang,Xinfang Zhang,Zhiyu Yi,Jihai Tang,Pingan Yang,Rui Cai,Shuang Yi,Jinsong Rao,Yuxin Zhang
In this work, a novel core-shell structure material, NiFe layered double hydroxide (NiFe LDH) loaded on SiO2microspheres (SiO2@NiFe LDH), was synthesized by a one-step hydrothermal method, and the spontaneous electrostatic self-assembly process. The morphology, structure, and microwave absorption properties of SiO2@NiFe LDH nanocomposites with different NiFe element ratios were systematically investigated. The results show that the sample of SiO2@NiFe LDH-3 nanocomposite has excellent microwave absorption properties. It exhibits broadband effective absorption bandwidth (RL < −10 dB) of 8.24 GHz (from 9.76 GHz to 18.0 GHz) and the reflection loss is −53.78 dB at the matched thickness of 6.95 mm. It is expected that this SiO2@NiFe-LDH core-shell structural material can be used as a promising non-precious, metal-based material microwave absorber to eliminate electromagnetic wave contamination.Keywords:SiO2microspheres;LDH;microwave absorption;core-shell structure
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2022
·
IF 6.371
Wei Yuan,Lichun Cheng,Tianrui Xia,Yucheng Chen,Qianxing Long,Qingrong Yao,Shunkang Pan,Chaohao Hu
Perovskite LaCoO 3 has unique mixed ionic electronic and structural defects, which has high research value in microwave absorption field. LaCoO 3 precursor was prepared by sol-gel method, and LaCo 1− x Fe x O 3 (Fe-LCO, x = 0, 0.05, 0.1 and 0.15) with rhombic symmetric structure was successfully synthesized at 600 °C. By refinement of X-ray diffraction (XRD) (Rietveld analysis), it was found that Fe doping makes LaCoO 3 lattice constant and cell volume increase. As a dielectric loss microwave absorbing material, the electromagnetic attenuation of LaCoO 3 is mainly due to the conduction loss, while the interface and dipole polarization are secondary reasons. It finds that Fe doping can improve the wave absorption performance of LaCoO 3 . The best absorbing performance was obtained when Fe content is x = 0.1, with the maximum reflection loss of − 38.99 dB at 10.8 GHz and the effective absorption bandwidth (RL<−10 dB) is 4.48 GHz, while the corresponding thickness was only 3 mm. In summary, LaCoO 3 has broad application prospects in X and Ku bands.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）