Improving the electromagnetic wave absorption properties of zinc ferrite-containing N-doped carbon composites by the introduction of Fe4N

The design of composites rich heterogeneous interfaces to enhance interfacial polarization is an effective way to boost electromagnetic waves (EMW) absorption performance. In this work, multi-component electromagnetic ZnFe 2 O 4 /Fe/Fe 4 N/N-doped carbon (ZnFe 2 O 4 /Fe/Fe 4 N/N-C) composites were successfully fabricated by carbonization of core/shell/shell ZnFe 2 O 4 @PDA@PPy precursors at 800 °C under a N 2 atmosphere. The ZnFe 2 O 4 /Fe/Fe 4 N/N-C composites exhibit excellent low-frequency EMW absorption performance: the effective absorption bandwidth reached 8.41 GHz (3.57–11.98 GHz), covering the entire C-band (4–8 GHz) and X-band (8–12 GHz) at a thickness of 4.5 mm with a minimum reflection loss (RL min ) of −36.13 dB at 4.54 GHz. The excellent property was attributed to the abundant heterogeneous interfaces in the ZnFe 2 O 4 /Fe/Fe 4 N/N-C composites with maximized polarization loss. Further, magnetic loss were enhanced by the introduction of Fe 4 N. This work demonstrates that the creation of heterogeneous interfaces via adding extra components is an effective strategy in the design of efficient low-frequency EMW absorbers.