Effective dielectric attenuation for excellent microwave absorption with broadband response of carbon hollow microspheres derived from resin  

作　　者：Kexin Jin Xueai Li Huimin Tang Yuning Shi Chunsheng Wang Wanchun Guo Kesong Tian Haiyan Wang 

机构地区：[1]Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse,State Key Laboratory of Metastable Materials Science and Technology,School of Environmental and Chemical Engineering,Yanshan University,Qinhuangdao,066004,China [2]School of Vehicle and Energy,Yanshan University,Qinghuangdao,066004,China

出　　处：《Journal of Materials Science & Technology》2024年第10期224-233,共10页材料科学技术（英文版）

基　　金：National Natural Science Foundation of China(grant No.51802278);Natural Science Foundation of Hebei Province(grant Nos.B2021203012,E2022203082);Department of Education of Hebei Province(grant No.QN2021140).

摘　　要：Carbon hollow microspheres as microwave absorption materials(MAMs)are of great significance in the research focuses owing to their lightweight,good impedance matching,and modifiable dielectric proper-ties.However,it is still a huge challenge to distinguish the contribution of dielectric attenuation between carbon intrinsic feature and hollow structure due to the lack of appropriate model materials.Then,the inadequate analysis of effective dielectric attenuation resulted in the construction of carbon hollow mi-crospheres semiempirical and often lacked precise modification of microstructure.Herein,a series of car-bon hollow microspheres with controllable graphitization and thickness of shell derived from phenolic resin coated on polystyrene microspheres that fully decomposed were synthesized,which is free of the impact of template residue.The carbon fragments ground from hollow microspheres exhibit the same broadband response as hollow microspheres,with effective bandwidth(RL<-10 dB)of 7.6 GHz,while their electromagnetic wave loss mechanisms are distinct.The high dielectric loss of carbon fragments with the same intrinsic characteristics as carbon hollow microspheres is mainly caused by dipole po-larization relaxation and enhancement of electrical conductivity ascribed to overlapping between carbon sheets.For the hollow structure,in addition to dipole polarization relaxation attributed to carbon intrin-sic feature,the effective dielectric loss is also comprised of the interfacial polarization in advantage due to the effective heterogeneous interface between air and carbon shell.This work provides a simplified model to clarify the effect of carbon intrinsic feature and microstructure on the dielectric loss of carbon hollow microspheres.

关 键 词：Effective dielectric attenuation Microwave absorption Broadband response Hollow microspheres Carbon derived from resin 

分 类 号：TB383.1[一般工业技术—材料科学与工程]