Boosting Microwave Absorption Performance of Bio-gel Derived Co/C Nanocomposites

Yiming Zhong1,2

Dechun Liu3

Qiuyun Yang1

Yunpeng Qu1,Email

Changyou Yu2

Kelan Yan4,Email

Peitao Xie2,Email

Xiaosi Qi1

Zhanhu Guo5

Zhexenbek Toktarbay6,Email

1College of Physics, Guizhou University, Guiyang, 550025, China.
2College of Materials Science and Engineering, Qingdao University, Qingdao, 266071, China.
3Qingdao Municipal Hospital, Qingdao, 266000, China.
4State Key Laboratory of Material-Oriented Chemical Engineering, College of Chemical Engineering, Nanjing Tech University, Nanjing, 210009, China.
5Integrated Composites Lab, Department of Mechanical and Construction Engineering, Northumbria University, Newcastle Upon Tyne, NE1 8ST, UK.
6Laboratory of Engineering Profile, Satbayev University, Satbayev St. 22a, Almaty 050013, Kazakhstan.

Abstract

The Co/C nanocomposites toward outstanding electromagnetic (EM) microwave absorption were meticulously designed and prepared by bio-gel method. The Co nanoparticles were embedded into the carbon network constructed by agar powder. Our obtained Co/C nanocomposites exhibited excellent EM wave absorption performance including wide bandwidth (7.1 GHz), thin thickness (1.71 mm), light weight and wide effective absorbing frequency. Dielectric relaxation at multilayer interfaces, porous biomass carbon materials and magnetic Co nanoparticles are the main sources for enhancing the wave absorption properties. The amorphous carbon in the material prevents the condensation and oxidation of magnetic Co nanoparticles, thus contributing to the generation of good impedance matching. On the basis of the percolation theory, the optimal Co content was determined, and a percolation model suitable for Co/C materials was established. 

Boosting Microwave Absorption Performance of Bio-gel Derived Co/C Nanocomposites