Dynamically frequency-tunable and environmentally stable microwave absorbers  

作　　者：Xiao Liu Lihong Wu Jun Liu Haiming Lv Pengpeng Mou Shaohua Shi Lei Yu Gengping Wan Guizhen Wang 

机构地区：[1]Key Laboratory of Pico Electron Microscopy of Hainan Province,Center for Advanced Studies in Precision Instruments,Hainan University,Haikou,Hainan,China [2]Center for New Pharmaceutical Development and Testing of Haikou,Center for Advanced Studies in Precision Instruments,Haikou,Hainan,China [3]State Key Laboratory of Marine Resource Utilization in South China Sea,School of Material Science and Engineering,Hainan University,Haikou,Hainan,China

出　　处：《Carbon Energy》2024年第10期225-238,共14页碳能源(英文)

基　　金：supported by the National Natural Science Foundation of China(grants 22278101,22068010,and 52365044);the Natural Science Foundation of Hainan Province(grants 120RC454 and 519QN176);the Innovation Project for Scientific and Technological Talents in Hainan Province(grant KJRC2023C08)。

摘　　要：The threat to information security from electromagnetic pollution has sparked widespread interest in the development of microwave absorption materials(MAMs).Although considerable progress has been made in high-performance MAMs,little attention was paid to their absorption frequency regulation to respond to variable input frequencies and their stability and durability to cope with complex environments.Here,a highly compressible polyimide-packaging carbon nanocoils/carbon foam(PI@CNCs/CF)fabricated by a facile vacuum impregnation method is reported to be used as a dynamically frequency-tunable and environmentally stable microwave absorber.PI@CNCs/CF exhibits good structural stability and mechanical properties,which allows precise absorption frequency tuning by simply changing its compression ratio.For the first time,the tunable effective absorption bandwidth can cover the whole test frequency band(2−18 GHz)with the broadest effective absorption bandwidth of 10.8 GHz and the minimum reflection loss of−60.5 dB.Moreover,PI@CNCs/CF possesses excellent heat insulation,infrared stealth,self-cleaning,flame retardant,and acid-alkali corrosion resistance,which endows it high reliability even under various harsh environments and repeated compression testing.The frequency-tunable mechanism is elucidated by combining experiment and simulation results,possibly guiding in designing dynamically frequency-tunable MAMs with good environmental stability in the future.

关 键 词：carbon nanocoils dynamic frequency tuning environmental stability microwave absorption POLYIMIDE ultrawide tuning ranges 

分 类 号：TB34[一般工业技术—材料科学与工程]