Fe@Fe3C Core-Shell Nanoparticles Embedded in Polyvinyl Alcohol-Derived Porous Carbon toward Light and High-Performance Microwave Absorption

High-performance microwave absorbents play a key role in information technology field. In this work, excellent microwave absorption property was achieved via embedded Fe@Fe3C core-shell nanoparticles in polyvinyl alcohol-derived porous carbon matrix. The results indicate that the microwave absorption performance will be greatly enhanced due to the interface between the nanoparticles and matrix, as well as the core-shell and porous structure, increase the energy consumption capacity via dipole polarization, interface loss and the multiple reflection/scattering. The maximum reflection loss (RLmax) reaches -56.88 dB at 11.3 GHz with the thickness of 2.11 mm, and the effective absorption bandwidth (EAB, RL <-10 dB) can get up to 5.2 GHz (from 12.9 to 18 GHz) with the thickness of 1.64 mm. Moreover, due to the low density of the porous carbon matrix, the total weight of the absorbents can be greatly induced, which provides an efficient way for lightweight and high-performance microwave absorption materials design.