Realizing optimized interfacial polarization and impedance matching with CNT-confined Co nanoparticles in hollow carbon microspheres for enhanced microwave absorption  

作　　者：Chang Zhang Kaicheng Luo Jiwei Liu Huibin Zhang Chunyang Xu Ruixuan Zhang Yifeng Cheng Jincang Zhang Limin Wu Renchao Che 

机构地区：[1]Zhejiang Laboratory,Hangzhou 311100,China [2]Laboratory of Advanced Materials,Shanghai Key Lab of Molecular Catalysis and Innovative Materials,Academy for Engineering&Technology,Fudan University,Shanghai 200438,China [3]Inner Mongolia University,Hohhot 010021,China

出　　处：《Journal of Materials Science & Technology》2024年第8期1-9,共9页材料科学技术（英文版）

基　　金：supported by the National Natural Science Foundation of China(Nos.52231007,51725101,11727807);the Ministry of Science and Technology of China(Nos.2021YFA1200600 and 2018YFA0209102).

摘　　要：The hollow porous structure with exceptional interfacial effect and customizable internal environment shows significant potential for application as electromagnetic shielding and absorption materials.However,designing hollow porous electromagnetic absorbers with both desirable impedance matching and high loss capability remains a challenge.Herein,3D hollow porous electromagnetic microspheres were constructed by assembling 0D Co magnetic nanoparticles,1D carbon nanotubes,and 2D carbon nanosheets.Due to the sufficient sites for Co^(2+)riveting,the high loading of magnetic carbon nanotubes(CoNC)and porous carbon spheres formed high-density interfaces,enhancing the interfacial polarization.Furthermore,high-density CoNC were grown in situ on the hollow porous carbon(HPC)microsphere,forming a highly dispersed 3D magnetic network that inhibited the aggregation of magnetic nanoparticles and enhanced magnetic coupling.Therefore,the asprepared CoNC/HPC microspheres exhibited excellent microwave absorption(MA)performance,with a minimum reflection loss of-33.2 dB and an effective bandwidth of 5.5 GHz at a thickness of only 1.8 mm.The interfacial polarization mechanism for enhanced MA performance was demonstrated by electron holography and density functional theory calculations.Magnetic holography and micromagnetic simulations also revealed magnetic confinement and coupling mechanism.This work provides a new approach for designing electromagnetic absorbers with optimized impedance matching and loss capability.

关 键 词：Microwave absorption Hollow porous structure Multidimensional assembly Interfacial polarization Magnetic coupling 

分 类 号：TB383[一般工业技术—材料科学与工程]