Wheat straw-derived magnetic carbon foams: In-situ preparation and tunable high-performance microwave absorption  

作　　者：Guangjun Gou Fanbin Meng Huagao Wang Man Jiang Wei Wei Zuowan Zhou 

机构地区：[1]Key Laboratory of Advanced Technologies of Materials(Ministry of Education),School of Materials Science and Engineering,Southwest Jiaotong University,Chengdu 610031,China

出　　处：《Nano Research》2019年第6期1423-1429,共7页纳米研究（英文版）

基　　金：the National Natural Science Foundation of China (No.51573149);the Fundamental Research Funds for the Central Universities (No.2682016CX069);the Science and Technology Planning Project of Sichuan Province (Nos.2018GZ0132 and 2018GZ0427);Sichuan Province Science and Technology Innovation Talent Project (No.2017072).

摘　　要：Recently,biomass-derived three-dimensional (3D) porous carbon materials have been gaining more interest as promising microwave absorbers due to their low cost,vast availability,and sustainability.Here,a novel 3D interconnected porous magnetic carbon foams are in-situ synthesized via a combination of sol-gel and carbonization process with wheat straw as the carbon source and FeCl3·6H2O as the magnetic regulating agent.During the process of foams formation,the lignocelluloses from the steam-exploded wheat straw are converted into interconnected carbon sheet networks with hierarchical porous structures,and the precursor FeCl3·6H2O is converted into magnetic nanoparticles uniformly embedded in the porous carbon foams.The generated magnetic nanoparticles are benefit to enhance the interface polarization and magnetic loss ability to improve the efficient complementarities between the dielectric and magnetic loss,thus increasing the impedance matching.The obtained sample treated at 600 ℃ displays the best microwave absorption (MA) performance.It presents a minimal reflection loss (RL) of-43.6 dB at 7.1 GHz and the effective bandwidth (RL <-10 dB) is 3.3 GHz with the thickness of 4.7 mm.The 3D porous structure,multi-interfaces and the synergy of dielectric loss and magnetic loss make great contribution to the outstanding MA performance.

关 键 词：WHEAT STRAW MAGNETIC biomass carbon FOAMS microwave absorption interface polarization IMPEDANCE matching 

分 类 号：O4[理学—物理]