Construction of iron oxide@C@Fe heterointerfaces by oxygen atmosphere heat treatment for enhanced microwave absorption performance

Carbon and iron-based materials are the two most extensively implemented microwave absorption materials. In this paper, carbon/iron-based wave absorption composite materials with tremendous dielectric and magnetic loss were successfully synthesized by carbonizing iron (III) acetylacetonate (Fe(acc)3). The heterointerfaces were constructed by oxidation heat treatment to further regulate the dielectric loss and optimize the impedance matching of the composite, and improve the microwave absorption performance. Eventually, ultra-thin lightweight composite materials were prepared. When the thickness of the absorbing coating was only 1.01 mm, the minimum reflection loss (RLmin) value of the composite was -15.8 dB with 50 % filling. In addition, the effective absorption bandwidth (EAB) (RL <= -10 dB) was highly up to 8.8 GHz (9.2--18 GHz).