title: Porous CNTs/Co Composite Derived from Zeolitic Imidazolate Framework: A Lightweight, Ultrathin, and Highly Efficient Electromagnetic Wave Absorber.
abstract: Porous carbon nanotubes/cobalt nanoparticles (CNTs/Co) composite with dodecahedron morphology was synthesized by in situ pyrolysis of the Co-based zeolitic imidazolate framework in a reducing atmosphere. The morphology and microstructure of the composite can be well tuned by controlling the pyrolysis conditions. At lower pyrolysis temperature, the CNTs/Co composite is composed of well-dispersed Co nanoparticles and short CNT clusters with low graphitic degree. The increase of pyrolysis temperature/time promotes the growth and graphitization of CNTs and leads to the aggregation of Co nanoparticles. The optimized CNTs/Co composite exhibits strong dielectric and magnetic losses as well as a good impedance matching property. Interestingly, the CNTs/Co composite displays extremely strong electromagnetic wave absorption with a maximum reflection loss of -60.4 dB. More importantly, the matching thickness of the absorber is as thin as 1.81 mm, and the filler loading of composite in the matrix is only 20 wt %. The highly efficient absorption is closely related to the well-designed structure and the synergistic effect between CNTs and Co nanoparticles. The excellent absorbing performance together with lightweight and ultrathin thickness endows the CNTs/Co composite with the potential for application in the electromagnetic wave absorbing field.
authors.affiliation: School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
authors.forename: Yichao
authors.initials: Y
authors.lastname: Yin
authors.affiliation: School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
authors.forename: Xiaofang
authors.identifier: http://orcid.org/0000-0002-2023-9890
authors.initials: X
authors.lastname: Liu
authors.affiliation: Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, China.
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Wei
authors.affiliation: School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
authors.forename: Ronghai
authors.initials: R
authors.lastname: Yu
authors.affiliation: School of Materials Science and Engineering, Beihang University , Beijing 100191, China.
authors.forename: Jianglan
authors.initials: J
authors.lastname: Shui
keywords: CNTs/Co; electromagnetic wave absorption; lightweight; ultrathin; zeolitic imidazolate framework