Constructing mixed-dimensional lightweight flexible carbon foam/carbon nanotubes-based heterostructures: An effective strategy to achieve tunable and boosted microwave absorption

Taking full advantage of interface engineering to strengthen interface polarization is an effective strategy to improve microwave absorption. Therefore, constructing the mixed-dimensional heterostructures and/or threedimensional (3D) interconnected network structures should be attractive pathways to create the abundant interfaces for enhanced interfacial effect. Herein, mixed-dimensional framework structure carbon foam (CF)/ carbon nanotubes (CNTs)@Fe3C@Fe3O4 samples consisting of 3D CF, one-dimensional (1D) CNTs and zerodimensional (0D) Fe3C@Fe3O4 nanoparticles were elaborately designed and produced through a simple catalytic chemical vapor deposition process. The as-prepared CF/CNTs@Fe3C@Fe3O4 heterostructures with the different contents of CNTs could be selectively produced by regulating the pyrolysis time. Owing to the unique structure and excellent synergistic effects, the obtained mixed-dimensional CF/CNTs@Fe3C@Fe3O4 samples presented the excellent comprehensive electromagnetic wave absorption performances (EMWAPs) including strong absorption capabilities, broad absorption bandwidths, thin matching thicknesses and low densities. Furthermore, the obtained results demonstrated that the enhanced content of CNTs greatly boosted their conduction and polarization loss abilities, which resulted in the enhanced comprehensive EMWAPs. Therefore, our findings not only offered a simple strategy to produce the mixed-dimensional framework structure magnetic CF/ CNTs-based heterostructures as excellent lightweight high-efficiency microwave absorbers, but also provided an effective pathway to make the best of interface engineering for enhancing interface polarization.

Automated summary

Taking full advantage of interface engineering to strengthen interface polarization is an effective strategy to improve microwave absorption. Constructing mixed-dimensional heterostructures and/or three-dimensional interconnected network structures can create abundant interfaces for enhanced interfacial effect. The mixed-dimensional CF/CNTs@Fe3C@Fe3O4 samples with different contents of CNTs exhibited excellent comprehensive electromagnetic wave absorption performances including strong absorption capabilities, broad absorption bandwidths, thin matching thicknesses, and low densities. Increasing the content of CNTs greatly enhanced their conduction and polarization loss abilities, resulting in enhanced comprehensive electromagnetic wave absorption performances.