Superior Microwave Absorption Properties Derived from the Unique 3D Porous Heterogeneous Structure of a CoS@Fe3O4@rGO Aerogel

Abstract

A novel CoS@Fe3O4@rGO aerogel with a unique 3D porous heterostructure was prepared via the solvothermal method, in which cobalt sulfide (CoS) microspheres embedded with Fe3O4 nanoparticles were randomly scattered on reduced graphene oxide (rGO) flakes. The introduction of magnetic Fe3O4 nanoparticles and rGO regulated the impedance matching, and the excellent electromagnetic wave (EMW) absorption capability of the CoS@Fe3O4@rGO aerogel could be attributed to optimal dielectric loss and abundant conductive networks. The results demonstrated that the minimum reflection loss (RL) value of CoS@Fe3O4@rGO aerogel was −60.65 dB at a 2.5 mm coating thickness with an ultra-wide bandwidth of 6.36 GHz (10.24–16.6 GHz), as the filler loading was only 6 wt%. Such a lightweight CoS@Fe3O4@rGO aerogel with an outstanding absorbing intensity and an ultra-wide effective absorption bandwidth could become a potential EMW absorber.

Electromagnetic Absorption by Magnetic Oxide Nanomaterials: A Review

“…Samples with a thickness of 2 mm showed an RL bandwidth below −10 dB at 2.4 GHz and a minimum reflection loss of −25 dB at 10 GHz. Liu et al 67 developed a novel CoS@ Fe 3 O 4 @RGO aerogel with a three-dimensional porous heterogeneous structure. The CoS microspheres were randomly dispersed with many Fe 3 O 4 nanoparticles on a RGO sheet, which formed a unique three-dimensional porous heterogeneous structure (Figure 5c).…”

“…(c) SEM images of CoS@Fe 3 O 4 @RGO. Reproduced with permission from ref . Copyright 2020 Multidisciplinary Digital Publishing Institute.…”

Enhanced microwave absorption performance of MOF-derived hollow Zn-Co/C anchored on reduced graphene oxide*

“…[1][2][3] With the popularity of electronic devices, electromagnetic radiation pollution has become an urgent issue. [4][5][6] In order to protect human beings and high-end devices from electromagnetic radiation, finding a microwave absorbing material with high performance has received significant attention. Therefore, it is necessary to research effective microwave absorbers with strong microwave absorption, low cost, light weight, thin thickness and broad absorption bandwidth.…”