Materials
·
2020
·Vol. 13
·期 23
·5331
·
IF 3.057
Yue Yuan,Shicheng Wei,Yi Liang,Bo Wang,Yujiang Wang
Cobalt ferrite is synthesized via a simple solvothermal method. Then, the effect of the degree of cobalt-ferrite growth on its morphology, structure, electromagnetic performance, and microwave absorption is studied as a function of the solvothermal reaction time. When the reaction time during synthesis is 8 h, the structure of cobalt ferrite is hollow spheres. In addition, when the reaction time is 12 h and 16 h, it becomes a submicron sphere with a diameter of 100–150 nm. With the increase of reaction time, cobalt ferrite underwent the process of cobalt ferrite formation, hollow structure formation, hollow structure disappearance, agglomeration separation and reagglomeration in 4–16 h. In general, CoFe2O4-8h shows better microwave absorption-the effective absorption bandwidth is 9.84 GHz (6–15.84 GHz) for a thickness of 1.72–3.72 mm. This represents a minimum return loss of −47.24 dB. A better understanding of both the synthesis parameters and the relationship between structure and electromagnetic properties can open new possibilities for applications and the development of microwave absorbing materials.Keywords:cobalt ferrite;reaction time;structure;microwave absorption properties
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
COMPOSITES SCIENCE AND TECHNOLOGY
·
2019
·
IF 6.309
Qixin Yang,Yiyuan Shi,Yu Fang,Yubing Dong,Qingqing Ni,Yaofeng Zhu,Yaqin Fu
A novel ternary nanocomposite of Fe 3 O 4 functionalized porous biomass carbon decorated by aligned polyaniline (A-PANI/Fe 3 O 4 /PBC) was successfully fabricated by hydrothermal and in situ oxidative polymerization. The morphology and structure of the composite was characterized by X-ray diffraction, fourier transform infrared spectra, scanning electron microcopy, transmission electron microscopy , X-ray photoelectron spectra and vibrating sample magnetometer . The microwave absorbing properties of A-PANI/Fe 3 O 4 /PBC composite were investigated in the frequency of 2–18 GHz. The results indicated that the A-PANI/Fe 3 O 4 /PBC composite possess excellent microwave absorbing performance, and the minimum reflection loss can be up to −44.8 dB at 10.67 GHz, effective absorbing bandwidth ( RL < −10 dB) reaches 4.69 GHz with a thickness of 2.7 mm. The excellent microwave absorbing performance of composite was mainly related to the multi-loss mechanisms, good impedance matching, synergistic and geometrical effect of porous biomass carbon, magnetic particles and aligned PANI.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2018
·
IF 3.057
Mingxu Sui,Tianqi Fu,Xiaodong Sun,Guangzhen Cui,Xuliang Lv,Guangxin Gu
Unary and binary M 2+ (M=Mn, Co, Ni, Zn) substituted hollow Fe 3 O 4 were prepared by one-step solvothermal method. The crystallographic structure, morphology, element components and microwave absorbing properties of as-prepared products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM), Energy-dispersive X-ray (EDX) and vector network analyzer (VNA). The unary and binary Co 2+ substitution of hollow Fe 3 O 4 could result in a significant improvement of microwave absorption performance, including the expanding of effective absorption bandwidth, the thinner thickness and the increment of absorbing intensity. The sample of CoFe 2 O 4 could reach an optimal reflection loss of − 28.78 dB at 15.52 GHz under the thickness of 1.5 mm, moreover, the efficient absorption bandwidth (less than −10 dB) is expanded to 5.56 GHz which is most outstanding among these samples. The minimum reflection loss of Co 0.75 Zn 0.25 Fe 2 O 4 could reach − 49.60 dB at 9.88 GHz under the thickness of 2 mm. The as-prepared products could be used as microwave absorber with the advantages of strong absorption, broad bandwidth and thin thickness. The favorable performance could be attributed to the strong magnetic loss, dielectric loss and good impedance matching properties.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CARBON
·
2020
·
IF 8.821
Xiaochuang Di,Yan Wang,Yuqiao Fu,Xinming Wu,Ping Wang
Thin and lightweight absorbers with strong absorption capacity are future development directions in the field of electromagnetic wave (EMW) absorption. Based on two microwave-absorbing mechanisms, the three-dimensional (3D) porous carbon materials derived from wheat flour were prepared via pyrolysis carbonization . Then, ZnFe 2 O 4 nanospheres were synthesized and distributed on the surface of carbon skeleton by simple solvothermal method. Results showed that microwave absorption performance was significantly improved due to synergistic effects between ZnFe 2 O 4 nanospheres and carbon matrix. With absorber thickness of only 1.8 mm and low filler loading of 20 wt%, the minimum reflection loss could reach as low as −54.1 dB at 14.1 GHz. The widest effective absorption bandwidth ranged from 9.2 GHz to 15.0 GHz (5.8 GHz) with a thickness of 2.5 mm when the filler loading was 10 wt%, covering 36% of entire measured bandwidth. As an absorber, 3D porous carbon@ZnFe 2 O 4 composite exhibited ideal microwave absorption properties because of synergistic effects between dielectric and magnetic loss, well-matched impedance, interfacial polarization , Debye relaxation process as well as multiple reflection and scattering. Considering excellent EMW absorption performance, the porous carbon@ZnFe 2 O 4 composite fabricated by a simple method can provide a new inspiration for designing structure and composition of lightweight microwave absorbers.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Jiabao Zang,Haifeng Li,Qingzhi Zhu,Ziheng Wang,Hubuli Bazaerbieke,Li Sun,Meijie Zhang
There are few reports about the electromagnetic wave (EMW) absorption properties of α−SiC based composites, and almost all of them focus on β−SiC polymorphs. In this study, α−SiC p /α−SiC nw /SiO 2 /C hybrid composites (sample SiC−C1500) with heterostructure α−SiC nanowires (α−SiC nw ) of multiple interfaces 4H−SiC/6H−SiC/SiO 2 /C were successfully prepared using mixed powder (α−SiC+m−SiO 2 +C) as raw material based on the heterogeneous nucleation−growth mechanism, and their microwave absorption properties were investigated. Meanwhile, the samples SiC−V2150 and Si−C1500 were obtained by vacuum calcination (α−SiC+m−SiO 2 +C) at 2150 0 C and carbothermal reduction (Si+m−SiO 2 +C) at 1500 0 C, respectively, and their phase compositions were α−SiC p /C and β−SiC p /β−SiC nw /SiO 2 /C, respectively. The sample SiC−C1500 exhibited excellent EMW absorption properties, with a minimum reflection loss (RL min ) value of −18.37 dB at a thickness of 1.3 mm, and a maximum effective absorption bandwidth (EAB max ) value of 4.9 GHz at a thickness of 1.5 mm. In contrast, the EMW absorption performance of the samples SiC−V2150 and Si−C1500 was obviously poor, which was consistent with the RCS (Radar Cross−Section) simulation results. The formation of α−SiC p /α−SiC nw /SiO 2 /C composites (sample SiC−C1500) containing 4H−SiC/6H−SiC/SiO 2 /C multi-interfaces heterostructure α−SiC nanowires (α−SiC nw ) was analyzed. The excellent EMW absorption performance of SiC−C1500 sample could be attributed to the effective regulation of α polymorphs, nanowire heterostructure, multi−component hybridization. This study supplies a helpful experience and reference for improving the high temperature EMW absorption performance of SiC matrix composites.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2024
·
IF 5.8
Kai Wang,Zhenying Liu,Shouwu Huang,Jiayi Song,Shaofeng Dong,Tingting Pan,Qiaoyuan Wang,Yin Liu
Ni 0.2 Mn 0.4 Zn 0.4 Fe 2 O 4 (NMZF) nanoparticles were anchored on the surface of MXene(Ti 3 C 2 T x ) to form Ti 3 C 2 T x /NMZF nanocomposites for optimization of microwave absorption performance. The Ti 3 C 2 T x /NMZF nanocomposites were synthesized by using a four-step strategy, including sonication, stirring, hydrothermal reduction and vacuum drying. More than 40 percent of the NMZF nanoparticles in this nanocomposite were assembled to form a conductive network. Meanwhile, the multilayer MXene acted as a framework to host the NMZF nanoparticles, providing dipolar polarization, interfacial polarization and eddy current loss. Benefiting from the structure design of MXene, combined with magnetic materials and optimized impedance matching, the Ti 3 C 2 T x /NMZF exhibited a minimum reflection loss (RL min ) of −57.39 dB, with a thickness of 2.97 mm and an effective absorption bandwidth (EAB) of 3.2 GHz. Therefore, such a facile method could be used to construct nanocomposites with microwave absorption performance (-57.39 dB, 3.2 GHz), so as to address microwave pollution issues.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2019
·
IF 6.282
Huanmin Ji,Jinhuan Li,Jiaojiao Zhang,Yi Yan
Graphene/polyethylene glycol (GPEG) composite aerogels were fabricated by the reduction-assembly of graphene oxide (GO) in polyethylene glycol 400 (PEG400) and the following freeze-drying process. PEG400 can effectively avoid the agglomeration of graphene sheets and adjust the permittivity of GPEGs. These GPEGs show an outstanding improvement on microwave absorption performance when the additive amount of GO is 5–25 wt%. The minimum reflection loss (RL) can reach −43.2 dB at 13.8 GHz, and the effective absorption bandwidth (RL < −10 dB) was 5.30 GHz (9.6–14.9 GHz) with the absorber thickness of 2.35 mm when the additive amount of GO in absorber is only 7.5 wt%. These composite aerogels still maintain an ultralight nature (the density of 18.5–19.8 mg/cm 3 ). This work provides a facile preparation method to fabricate an exceptional microwave absorption material which possesses lightweight, economy and the high-efficient microwave absorption property.
研究领域:
材料科学
·
电磁学
✓ 已验证
产品关联
DOI
高影响因子
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
·
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
·
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
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
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
Acta Metallurgica Sinica-English Letters
·
2017
·Vol. 31
·期 2
·171-179
·
IF 1.292
Liu Pei-Jiang,Yao Zheng-Jun,Ng Vincent Ming Hong,Zhou Jin-Tang,Yang Zhi-Hong,Kong Ling-Bing
Microwave absorption properties of spherical NiO particles and Co 0.2 Ni 0.4 Zn 0.4 Fe 2 O 4 (CNZF) ferrites with single-layer and double-layer absorbers were studied in the frequency range of 2–18 GHz. The spherical NiO particles were synthesized by using a hydrothermal process, while the CNZF powders were prepared by using a sol–gel autoignition method. The double-layer absorbers, composed of 30 wt% NiO as matching layer and 30 wt% CNZF as absorption layer, with a total thickness of 3.2 mm, exhibited a maximum reflection loss ( R
L ) of –67.0 dB at 9.2 GHz and an effective absorbing bandwidth below –10 dB to be 3.9 GHz from 7.0 to 10.9 GHz. The excellent microwave absorption performance of the double-layer absorbers should be ascribed to the high impedance matching ratio, the great microwave attenuation capability, and well-coupled layer.
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）