The exploitation of electromagnetic wave absorption(EMA)materials has attracted ever-increasing atten-tion,not only because electromagnetic wave(EMW)originated from overuse of electronic products has threatened human'health seriously,but also because EMA materials can effectively protect radar stealth from being detected.However,it is still a challenge to obtain broadband and efficient EMA materials to satisfy practical applications.In this work,we developed a series of hierarchical CoFe alloy/porous car-bon@carbon nanotubes(CoFe/PC@CNTs)nanocomposites through revising the proportion of Fe2+in the metal-organic frameworks(MOFs)(CoFe-ZIF)precursor and one-step simple pyrolysis process.The cross deposition between CoFe alloy,carbon nanotubes(CNTs),and porous carbon(PC)formed a double con-ductive network,favoring for achieving excellent EMA property.Surprisingly,when the filler mass ratio is only 10 wt％,the optimized CoFe/PC@CNTs nanocomposites display the best EMA capability,whose min-imum reflection loss(RLmin)value is-68.94 dB at 13.69 GHz and the effective absorption band(EAB,＜-10 dB)reaches up 9.14 GHz with a matching thickness of 2.63 mm.In addition,the largest EAB can achieve up to 11 GHz(3.35-14.35 GHz)during all matching thicknesses.The splendid EMA performance benefits the favorable dielectric loss provided by the double conductive network,the good magnetic loss benefited from the evenly distributed CoFe alloy,the excellent impedance matching,rich transmission paths,and multiple polarization.Therefore,such EMA materials with super broadband absorbing provide desirable candidates for lightweight and high-efficient microwave absorbers.

Siyao Guo;Yunfeng Bao;Ying Li;Hailong Guan;Dongyi Lei;Tiejun Zhao;Baomin Zhong;Zhihong Li

School of Civil Engineering,Qingdao University of Technology,Qingdao 266033,China;Cooperative Innovation Center of Engineering Construction and Safety in Shandong Blue Economic Zone,Qingdao University of Technology,Qingdao 266033,China;Postdoctoral Workstation,Guangdong Dongpeng Holding Company Limited,Guangdong 528031,China;National Key Laboratory of Science and Technology for National Defence on Advanced Composites in special Environments,Harbin Institute of Technology,Harbin 150080,China

材料科学技术（英文版）

[1]Siyao Guo;Yunfeng Bao;Ying Li;Hailong Guan;Dongyi Lei;Tiejun Zhao;Baomin Zhong;Zhihong Li-.Super broadband absorbing hierarchical CoFe alloy/porous carbon@carbon nanotubes nanocomposites derived from metal-organic frameworks)[J].材料科学技术（英文版）,2022(23):218-228

Super,broadband,absorbing,hierarchical,CoFe,alloy,porous,carbon,nanotubes,nanocomposites,derived,from,metal,organic,frameworks,exploitation,electromagnetic,absorption,EMA,materials,has,attracted,increasing,atten,only,because,EMW,originated,overuse,electronic,products,threatened,human,health,seriously,also,effectively,protect,radar,stealth,being,detected,However,still,challenge,obtain,efficient,satisfy,practical,applications,In,this,developed,series,CNTs,through,revising,proportion,Fe2+in,MOFs,ZIF,precursor,one,step,simple,pyrolysis,process,cross,deposition,between,formed,double,network,favoring,achieving,excellent,property,Surprisingly,when,filler,mass,ratio,wt,optimized,display,best,capability,whose,imum,reflection,loss,RLmin,value,dB,GHz,EAB,reaches,matching,addition,largest,achieve,during,thicknesses,splendid,performance,benefits,favorable,dielectric,provided,by,conductive,good,benefited,evenly,distributed,impedance,rich,transmission,paths,multiple,polarization,Therefore,such,super,desirable,candidates,lightweight,high,microwave,absorbers

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