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International Journal of Smart and Nano Materials 2022年第3期13卷 465-480页

作者： Hongjiao Qu Peng Zheng Tao Wang Xingyu Yu Junjie Pan Xiaoli Fan Tengfei Zhang Xin Sun Jianping He College of Materials Science and Technology Centre for HydrogenergyJiangsu Key Laboratory of Materials and Technology for Energy ConversionNanjing University of Aeronautics and AstronauticsNanjingP.R.China AVIC Jiangxi Hongdu Aviation Industry Group Corporation LimitedJiangxiP.R.China School of Materials Science and Engineering Nanjing Institute of TechnologyNanjingP.R.China Science and Technology on Electromagnetic Scattering Laboratory BeijingP.R.China

Metal-organic framework materials(MOFs)have been widely stu-died because of their adjustable composition and controllable structure in the field of microwave absorption(MA).Therein,Prussian blue analogs(PBA)have attracted the attention of researchers with ultra-high metal content.However,the attenua-tion ability of microwave for PBA-based composites is still unsatis-factory up to now.Therefore,the NiFe/CoFe@C composites were prepared by carbonizing polymetallic PBA(NiCoFe PBA)materials in this work,and the influence of different metal alloy components on MA was explored by adjusting the ratio of metal ions(Ni^(2+)/Co^(2+)).Moreover,the NiFe/CoFe@C composites have rich interfaces and enhance the polarization loss due to the introduction of Ni and it has an optimal performance at 2.7 mm that is the reflection loss(RL)is−41.49 dB and an effective absorption bandwidth(EAB)is 7.12 GHz with 1/1(Ni^(2+)/Co^(2+)).The above data provides a research idea for obtaining light and efficient absorbers.

关键词： Prussian blue analogs carbon-based composites metal alloy polarization loss microwave absorption

Interface Engineering of Titanium Nitride Nanotube Composites for Excellent Microwave Absorption at Elevated Temperature

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Nano-Micro Letters 2024年第9期16卷 147-160页

作者： Cuiping Li Dan Li Shuai Zhang Long Ma Lei Zhang* Jingwei Zhang Chunhong Gong College of Chemistry and Molecular Sciences Henan UniversityKaifeng 475004People’s Republic of China National and Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004People’s Republic of China

Currently,the microwave absorbers usually suffer dreadful electromagnetic wave absorption(EMWA)performance damping at elevated temperature due to impedance mismatching induced by increased conduction loss.Consequently,the development of high-performance EMWA materials with good impedance matching and strong loss ability in wide temperature spectrum has emerged as a top priority.Herein,due to the high melting point,good electrical conductivity,excellent environmental stability,EM coupling effect,and abundant interfaces of titanium nitride(TiN)nanotubes,they were designed based on the controlling kinetic diffusion procedure and Ostwald ripening process.Benefiting from boosted heterogeneous interfaces between TiN nanotubes and polydimethylsiloxane(PDMS),enhanced polarization loss relaxations were created,which could not only improve the depletion efficiency of EMWA,but also contribute to the optimized impedance matching at elevated temperature.Therefore,the TiN nanotubes/PDMS composite showed excellent EMWA performances at varied temperature(298-573 K),while achieved an effective absorption bandwidth(EAB)value of 3.23 GHz and a minimum reflection loss(RLmin)value of−44.15 dB at 423 K.This study not only clarifies the relationship between dielectric loss capacity(conduction loss and polarization loss)and temperature,but also breaks new ground for EM absorbers in wide temperature spectrum based on interface engineering.

关键词： TiN nanotubes Interface engineering polarization loss Impedance matching Electromagnetic wave absorption performance

An Equivalent Substitute Strategy for Constructing 3D Ordered Porous Carbon Foams and Their Electromagnetic Attenuation Mechanism

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Nano-Micro Letters 2022年第10期14卷 15-35页

作者： Meng Zhang Hailong Ling Ting Wang Yingjing Jiang Guanying Song Wen Zhao Laibin Zhao Tingting Cheng Yuxin Xie Yuying Guo Wenxin Zhao Liying Yuan Alan Meng Zhenjiang Li College of Materials Science and Engineering College of Electromechanical EngineeringQingdao University of Science and TechnologyQingdao 266061People’s Republic of China State Key Laboratory Base of Eco-Chemical Engineering College of Chemistry and Molecular EngineeringCollege of Chemical Engineering in Gaomi CampusQingdao University of Science and TechnologyQingdao 266042People’s Republic of China

Three-dimensional(3D)ordered porous carbon is generally believed to be a promising electromagnetic wave(EMW)absorbing material.However,most research works targeted performance improvement of 3D ordered porous carbon,and the specific attenuation mechanism is still ambiguous.Therefore,in this work,a novel ultra-light egg-derived porous carbon foam(EDCF)structure has been successfully constructed by a simple carbonization combined with the silica microsphere template-etching process.Based on an equivalent substitute strategy,the influence of pore volume and specific surface area on the electromagnetic parameters and EMW absorption properties of the EDCF products was confirmed respectively by adjusting the addition content and diameter of silica microspheres.As a primary attenuation mode,the dielectric loss originates from the comprehensive effect of conduction loss and polarization loss in S-band and C band,and the value is dominated by polarization loss in X band and Ku band,which is obviously greater than that of conduction loss.Furthermore,in all samples,the largest effective absorption bandwidth of EDCF-3 is 7.12 GHz under the thickness of 2.13 mm with the filling content of approximately 5 wt%,covering the whole Ku band.Meanwhile,the EDCF-7 sample with optimized pore volume and specific surface area achieves minimum reflection loss(RL_(min))of−58.08 dB at 16.86 GHz while the thickness is 1.27 mm.The outstanding research results not only provide a novel insight into enhancement of EMW absorption properties but also clarify the dominant dissipation mechanism for the porous carbon-based absorber from the perspective of objective experiments.

关键词： Porous carbon foam Electromagnetic wave absorption Adjustable pore structure polarization loss Attenuation mechanism

Boosted electromagnetic wave absorption performance from synergistic induced polarization of SiC_(NWs)@MnO_(2)@PPy heterostructures

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Nano Research 2023年第2期16卷 3558-3569页

作者： Meng Zhang Laibin Zhao Wenxin Zhao Ting Wang Liying Yuan Yuying Guo Yuxin Xie Tingting Cheng Alan Meng Zhenjiang Li College of Electromechanical Engineering Key Laboratory of Polymer Material Advanced Manufacturing’s Technology of Shandong provinceCollege of Materials Science and EngineeringQingdao University of Science and TechnologyQingdao 266061China Key Laboratory of Optic-electric Sensing and Analytical Chemistry for Life Science MOEShandong Key Laboratory of Biochemical AnalysisCollege of Gaomi CampusCollege of Chemistry and Molecular EngineeringQingdao University of Science and TechnologyQingdao 266042China

In the last decade,electromagnetic pollution has caused people’s considerable attention.Developing absorbing material with low cost,lightweight,simple preparation,and high electromagnetic attenuation efficiency has become a feasible means to deal with this problem.In this work,core–shell SiC_(NWs)@MnO_(2)@PPy(NWs:nanowires,PPy:polypyrrole)heterostructures composed of SiC nanowires core,MnO_(2)nanosheets inter-layer,and PPy coating were successfully prepared through chemical vapor deposition and two-step electrodeposition process.Taking advantage of the interfacial polarization and dipole polarization,the obtained product displays excellent electromagnetic wave absorption performances with the minimum reflection loss(RLmin)of−50.59 dB when the matching thickness is 2.41 mm,and the optimal effective absorption bandwidth(EAB)value reaches to 6.64 GHz at a matching thickness of 2.46 mm,revealing that the SiC_(NWs)@MnO_(2)@PPy nanocomposite could be served as a promising electromagnetic wave absorbing material.On the basis of systematic analysis concerning the electromagnetic parameters,the dissipation process of the incident electromagnetic wave was demonstrated reasonably,which may provide a referable preparation strategy for novel heterostructures,especially nonmagnetic lightweight absorbing material.

关键词： SiC nanowires heterostructure polarization loss electromagnetic wave absorption attenuation mechanism

Boosted microwave absorption performance of transition metal doped TiN fibers at elevated temperature

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Nano Research 2023年第2期16卷 3570-3579页

作者： Cuiping Li Dan Li Lu Zhang Yahong Zhang Lei Zhang Chunhong Gong Jingwei Zhang Institute of Functional Polymer Composites College of Chemistry and Chemical EngineeringHenan UniversityKaifeng 475004China National&Local Joint Engineering Research Center for Applied Technology of Hybrid Nanomaterials Henan UniversityKaifeng 475004China Key Laboratory of Micro-Nano Materials for Energy Storage and Conversion of Henan Province Institute of Surface Micro and Nano MaterialsCollege of Chemical and Materials EngineeringXuchang UniversityXuchang 461000China

Due to the temperature and frequency response of electromagnetic(EM)loss,how to realize the effective design of microwave absorption materials(MWAMs)at elevated temperature is highly desirable for practical applications.Herein,transition metaldoped titanium nitride(M-TiN,M=Fe or Co)fibers were fabricated,the distortion of TiN lattice could cause the adjustable charge enrichment,which played a profound influence on the dielectric response and EM microwave absorption(EMWA)performances.Benefiting from the negative correlation between dielectric loss and temperature,more loss mechanism could be introduced,which would effectively enhance dielectric loss and EMWA performances at elevated temperature.The optimal EMWA performances of Fe-TiN fibers/polydimethylsiloxane(PDMS)composites were realized with a wide temperature range(298–423 K):the reflection loss(RL)could reach 99%(RLpolarization loss and conduction loss.Based on systematic analysis of the variable-temperature EM parameters and EMWA performances,the optimization of EMWA performances in wide temperature domain could be realized by introducing appropriate polarization loss and its compensating.Hopefully,this work provides a new strategy for regulating the dielectric response and designing effective MWAMs at elevated temperature.

关键词： transition metal-doped TiN polarization loss dielectric response electromagnetic microwave absorption

Simultaneous optimization of conduction and polarization losses in CNT@NiCo compounds for superior electromagnetic wave absorption

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Journal of Materials Science & Technology 2023年第35期166卷 34-46页

作者： Yongpeng Zhao Zhicheng Lin Li Huang Zitong Meng Hao Yu Xin Kou Zhiyong Zou Peng Huang Yuchao Wang Ding Xi Pengfei Yin Gehong Su Zhiqiang Fan Zhiping Su Dongbei Xu Lujun Pan Lijia Xu College of Mechanical and Electrical Engineering Sichuan Agricultural UniversityYa’an 625000China School of Education Northwest Normal UniversityLanzhou 730000China College of Graduate Sichuan Agricultural UniversityChengdu 610000China College of Science Sichuan Agricultural UniversityYa’an 625000China College of Agriculture Sichuan Agricultural UniversityChengdu 610000China School of Physics Dalian University of TechnologyDalian 116024China

polarization and conduction losses are the two most crucial dielectric loss mechanisms for carbon-based composites,but their synergistic effects in different frequency bands need to be further revealed.More importantly,for polarization and conduction losses,the strengthening of one party always comes at the expense of the other,which inevitably limits the overall performance of the absorbers.Herein,we have developed a composite of CNT and NiCo hybrid particles via a scalable wet chemical process and an-nealing method.Through the adjustment of the precursor and the annealing temperature,the conduction and polarization losses of the composite are optimized simultaneously.The optimized samples achieved the full absorption of the X and Ku bands under conditions of low filling rate and thin thickness.Further theoretical and experimental studies have revealed conduction loss and polarization loss laws at different frequency ranges.The synergistic effect of conductive loss and magnetic loss in the low-frequency region ensures that the sample exhibits high microwave dissipation performance.However,in the medium and high-frequency part,the magnetic loss can be almost ignored and the timely replenishment of polar-ization loss keeps the wave-absorbing performance at a high level.The excellent multi-band absorption characteristics make the as-obtained absorbers meet the needs of future applications.

关键词： CNT@NiCo compounds Conduction loss polarization loss Electromagnetic wave absorption

Controllable synthesis of mesoporous carbon hollow microsphere twined by CNT for enhanced microwave absorption performance

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Journal of Materials Science & Technology 2020年第24期59卷 164-172页

作者： Minghang Li Xiaomeng Fan Hailong Xu Fang Ye Jimei Xue Xiaoqiang Li Laifei Cheng Science and Technology on Thermostructural Composite Materials Laboratory Northwestern Polytechnical UniversityXi’an 710072China

The low dielectric loss of mesoporous carbon hollow microsphere(PCHM)requires high filler loading(higher than 20 wt%)when it is used as microwave absorbers.In order to decrease the filler loading of PCHM,a new strategy for synergistic increase of polarization and conductive loss was developed by twining PCHM with carbon nanotube(CNT)according to theoretic calculation.By the optimization of CNT content,the minimum reflection coefficient was -34.6 dB with a filler loading of only 10 wt%,which was much lower than -2.1 dB of PCHM.In addition,the effective absorption bandwidth was 3.6 GHz at X band with a thickness of 2.8 mm.The enhanced microwave absorption performance can be ascribed to the unique combination of hollow PCHM and one-dimensional CNT with higher graphitization degree,leading to increase of conductivity and heterogeneous interfaces.As a result,the conductive loss increased from 0.12 to 2.27 and polarization loss increased from 0.15 to 0.67,achieving the balance between attenuation ability and impedance match.

关键词： Microwave absorption Interfacial polarization Carbon polarization loss

3D carbon network supported porous SiOC ceramics with enhanced microwave absorption properties

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Journal of Materials Science & Technology 2020年第19期54卷 223-229页

作者： Chen Chen Sifan Zeng Xiaochun Han Yongqiang Tan Wanlin Feng Huahai Shen Shuming Peng Haibin Zhang Innovation Research Team for Advanced Ceramics Institute of Nuclear Physics and ChemistryChina Academy of Engineering PhysicsMianyang621900China

Porous SiOC ceramic was successfully prepared by pyrolysis of dimethylsilicone oil,silane coupling agent and melamine foam.The microwave absorbing properties of porous SiOC were studied for the first time.At the matching layer thickness of 3.0 mm,the paraffin-based composite with porous SiOC displays a minimum reflection coefficient(RC)of-39.13 d B(11.76 GHz)and an effective absorption bandwidth(EAB)of 4.64 GHz which are much larger than that of paraffin-based composite with ordinary SiOC.It is found that the porous structure of SiOC is crucial to achieve its high microwave absorption performance by improving both the polarization loss and conduction loss.The enhanced polarization loss is originated from the dipole polarization and interfacial polarization,while the improvement of conduction loss is attributed to the carbon skeleton of porous SiOC.These results indicate that porous SiOC ceramic is a promising candidate for high-performance ceramic-based microwave absorbing materials.

关键词： Porous structure polarization loss Conduction loss Dipole polarization Interfacial polarization