Rational Construction of Hierarchically Porous Fe-Co/N-Doped Carbon/rGO Composites for Broadband Microwave Absorption

Shanshan Wang; Yingchun Xu; Ruru Fu; Huanhuan Zhu; Qingze Jiao; Tongying Feng; Caihong Feng; Daxin Shi; Hansheng Li; Yun Zhao

doi:10.1007/s40820-019-0307-8

Rational Construction of Hierarchically Porous Fe-Co/N-Doped Carbon/rGO Composites for Broadband Microwave Absorption

Nanomicro Lett. 2019 Sep 13;11(1):76. doi: 10.1007/s40820-019-0307-8.

Authors

Shanshan Wang¹, Yingchun Xu¹, Ruru Fu¹, Huanhuan Zhu¹, Qingze Jiao^{1

2}, Tongying Feng², Caihong Feng¹, Daxin Shi¹, Hansheng Li¹, Yun Zhao³

Affiliations

¹ School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Zhuhai, 100081, People's Republic of China.
² School of Materials and the Environment, Beijing Institute of Technology, Zhuhai, 519085, People's Republic of China.
³ School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Zhuhai, 100081, People's Republic of China. zhaoyun@bit.edu.cn.

Abstract

Developing lightweight and broadband microwave absorbers for dealing with serious electromagnetic radiation pollution is a great challenge. Here, a novel Fe-Co/N-doped carbon/reduced graphene oxide (Fe-Co/NC/rGO) composite with hierarchically porous structure was designed and synthetized by in situ growth of Fe-doped Co-based metal organic frameworks (Co-MOF) on the sheets of porous cocoon-like rGO followed by calcination. The Fe-Co/NC composites are homogeneously distributed on the sheets of porous rGO. The Fe-Co/NC/rGO composite with multiple components (Fe/Co/NC/rGO) causes magnetic loss, dielectric loss, resistance loss, interfacial polarization, and good impedance matching. The hierarchically porous structure of the Fe-Co/NC/rGO enhances the multiple reflections and scattering of microwaves. Compared with the Co/NC and Fe-Co/NC, the hierarchically porous Fe-Co/NC/rGO composite exhibits much better microwave absorption performances due to the rational composition and porous structural design. Its minimum reflection loss (RL_min) reaches - 43.26 dB at 11.28 GHz with a thickness of 2.5 mm, and the effective absorption frequency (RL ≤ - 10 dB) is up to 9.12 GHz (8.88-18 GHz) with the same thickness of 2.5 mm. Moreover, the widest effective bandwidth of 9.29 GHz occurs at a thickness of 2.63 mm. This work provides a lightweight and broadband microwave absorbing material while offering a new idea to design excellent microwave absorbers with multicomponent and hierarchically porous structures.

Keywords: Broadband; Fe-doped Co-MOF; Hierarchically porous; Microwave absorption performance; rGO.