Construction of remarkable electromagnetic wave absorber from heterogeneous structure of Co-CoFe2O4@mesoporous hollow carbon spheres

Carbon nanomaterials have attracted a great deal of attention in various fields especially in electromagnetic wave absorption due to unique physical and chemical properties. Herein, a novel Co-CoFe2O4@mesoporous hollow carbon spheres (PCHMs) nanocomposites were prepared by two-facile steps, which included synthesizing three-dimensional mesoporous hollow carbon nanospheres (3D PCHMs) by hard template method, pyrolysis and etching process and in-situ growth of ultra-small Co-CoFe2O4 nanoparticles on PCHMs. The microscopic morphology and electromagnetic wave absorption mechanisms were discussed in depth. The synthesized CoCoFe2O4@PCHMs maintained a stable hollow and mesoporous structure and the Co-CoFe2O4 nanoparticles are uniformly distributed on the PCHMs. The complex permittivity and complex permeability could be effortlessly controlled by the content of Co-CoFe2O4 nanoparticles. Benefitting from the remarkable impedance matching under the influence of moderate complex permittivity and complex permeability, the minimum reflection loss (RLmin) of S2 exhibited -65.31 dB at 2.1 mm. The maximum effective absorption bandwidth (EAB) reached up to 8.48 GHz. The Co-CoFe2O4@PCHMs nanocomposites will have great potential application in electromagnetic wave absorption.

Automated summary

In this study, a novel Co-CoFe2O4@mesoporous hollow carbon spheres (PCHMs) nanocomposites were successfully prepared using two facile steps. The synthesized nanocomposites exhibited stable structure and excellent electromagnetic wave absorption properties, showing great potential for applications in the field of electromagnetic wave absorption.