Graphene/BN/Fe/BN Nanocomposites for Highly Efficient Electromagnetic Wave Absorption

A rational composition design is important for optimizing impedance matching and enhancing the reflection loss of microwave absorption materials. In this study, a Graphene/BN/Fe/BN nanocomposite was successfully prepared by a facile process, in which the boron nitride (BN) was anchored on the surface of the graphene and iron ball. As a result of the microwave-transparent feature of BN, the impedance matching of the Graphene/BN/Fe/BN nanocomposite was well adjusted by decreasing the dielectric constant and attenuation constant. Moreover, the introduction of thin BN on the surface of graphene could effectively increase the lamellar spacing, thereby enhancing the interfacial polarization. Ultimately, the microwave absorption property of the Graphene/BN/Fe/BN nanocomposite was optimized significantly, the minimum reflection loss could reach −44.53 dB at 1.4 mm, and the effective absorption bandwidth below −10 dB could reach 4.4 GHz with a filling loading of 40 wt % when the thickness was only 1.5 mm. Benefiting from the multicomponent design and structure regulation, the impedance matching and electromagnetic wave absorption performance of Graphene/BN/Fe/BN were optimized. This study paves the way for synthesizing high-efficiency microwave absorbers through structure design and compositional regulation.