Enhanced Microwave Absorption: The Composite of Fe3O4 Flakes and Reduced Graphene Oxide with Improved Interfacial Polarization

Herein, to further improve the microwave absorption performance, the composite of Fe 3 O 4 flakes and reduced graphene oxide (RGO/Fe 3 O 4 ) via hydrothermal method followed by H 2 reduction is rationally designed and synthesized. Compared with pure Fe 3 O 4 flakes and RGO/granular Fe 3 O 4 composite, the obtained RGO/Fe 3 O 4 exhibit remarkable enhancement of microwave absorption. The measurement results indicate that the maximum reflection loss of RGO/Fe 3 O 4 can reach −47.2 dB at the thickness of 2.4 mm and the effective absorption bandwidth less than −10 dB reaches 6.4 GHz (from 11.36 to 17.76 GHz), much higher than that of pure Fe 3 O 4 flakes and RGO/granular Fe 3 O 4 composite. The improved performances are believed to be from the rationally designed heterointerfaces, which are created by the combination of Fe 3 O 4 flakes and graphene. The construction of abundant heterointerfaces is a valid strategy to improve the microwave absorption performance.