Journal ArticleDOI
Microwave Absorption Enhancement of Multifunctional Composite Microspheres with Spinel Fe3O4 Cores and Anatase TiO2 Shells
TLDR
The results indicate that these Fe(3)O(4)@TiO(2) microspheres may be attractive candidate materials for microwave absorption applications.Abstract:
Multifunctional composite microspheres with spinel Fe(3)O(4) cores and anatase TiO(2) shells (Fe(3)O(4)@TiO(2)) are synthesized by combining a solvothermal reaction and calcination process. The size, morphology, microstructure, phase purity, and magnetic properties are characterized by scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM, selected-area electron diffraction, electron energy loss spectroscopy, powder X-ray diffraction, and superconducting quantum interference device magnetometry. The results show that the as-synthesized microspheres have a unique morphology, uniform size, good crystallinity, favorable superparamagnetism, and high magnetization. By varying the experimental conditions such as Fe(3)O(4) size and concentration, microspheres with different core sizes and shell thickneses can be readily synthesized. Furthermore, the microwave absorption properties of these microspheres are investigated in terms of complex permittivity and permeability. By integration of the chemical composition and unique structure, the Fe(3)O(4)@TiO(2) microspheres possess lower reflection loss and a wider absorption frequency range than pure Fe(3)O(4). Moreover, the electromagnetic data demonstrate that Fe(3)O(4@TiO(2) microspheres with thicker TiO(2) shells exhibit significantly enhanced microwave absorption properties compared to those with thinner TiO(2) shells, which may result from effective complementarities between dielectric loss and magnetic loss. All the results indicate that these Fe(3)O(4)@TiO(2) microspheres may be attractive candidate materials for microwave absorption applications.read more
Citations
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Journal ArticleDOI
Broadband and Tunable High‐Performance Microwave Absorption of an Ultralight and Highly Compressible Graphene Foam
Yi Zhang,Yi Huang,Tengfei Zhang,Huicong Chang,Peishuang Xiao,Honghui Chen,Zhiyu Huang,Yongsheng Chen +7 more
TL;DR: The broadband and tunable high-performance microwave absorption properties of an ultralight and highly compressible graphene foam (GF) are investigated and it is shown that via physical compression, the microwave absorption performance can be tuned.
Journal ArticleDOI
CoNi@SiO2@TiO2 and CoNi@Air@TiO2 Microspheres with Strong Wideband Microwave Absorption
TL;DR: Owing to the magnetic-dielectric synergistic effect, the obtained CoNi@SiO2 @TiO2 microspheres exhibit outstanding microwave absorption performance with a maximum reflection loss of -58.2 dB and wide bandwidth of 8.1 GHz.
Journal ArticleDOI
Temperature dependent microwave attenuation behavior for carbon-nanotube/silica composites
Bo Wen,Mao-Sheng Cao,Zhi-Ling Hou,Wei-Li Song,Lu Zhang,Ming-Ming Lu,Haibo Jin,Xiao-Yong Fang,Wenzhong Wang,Jie Yuan +9 more
TL;DR: In this paper, the authors evaluated the dielectric properties and microwave attenuation performances over the full X-band (8.2-12.4 GHz) at a wide temperature ranging from 100 to 500 °C.
Journal ArticleDOI
Thermally Driven Transport and Relaxation Switching Self-Powered Electromagnetic Energy Conversion.
TL;DR: Graphene networks with "well-sequencing genes" can serve as nanogenerators, thermally promoting electromagnetic wave absorption by 250%, with broadened bandwidth covering the whole investigated frequency, opening up an unexpected horizon for converting, storing, and reusing waste electromagnetic energy.
Journal ArticleDOI
Microwave Absorption Properties of Carbon Nanocoils Coated with Highly Controlled Magnetic Materials by Atomic Layer Deposition
Guizhen Wang,Zhe Gao,Shiwei Tang,Chaoqiu Chen,Feifei Duan,Shichao Zhao,Shiwei Lin,Yuhong Feng,Lei Zhou,Yong Qin +9 more
TL;DR: Atomic layer deposition is applied to coat carbon nanocoils with magnetic Fe(3)O(4) or Ni with coaxial multilayer nanostructures and exhibits remarkably improved microwave absorption properties compared to the pristine carbon Nanocoils.
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