Iron-nickel Compounds/RGO Heterogeneous for Tunable Microwave Absorption Frequency with Ultralow Filler Loading

We fabricate iron-nickel compounds/reduced graphene oxide (RGO) heterogeneous to obtain lightweight and high-efficiency microwave absorption materials with tunable absorption frequency. The method is using a facile hydrothermal route in combination with calcination at varying temperature of 500-700 ℃ with the obtained magnetic components as Fe0.64Ni0.36, Fe0.64Ni0.36@Fe2Ni2N, and Fe2Ni2N, respectively. Due to the strong interfacial polarization and dipole polarization, as well as conductive network related to the substantial number of interfaces, all the magnetic RGO hybrids presented remarkable electromagnetic wave attenuation ability even when the filler content is only 5.2 wt.%. More importantly, the optimization of the reflection loss and tunable absorption frequency could be successfully realized by tuning the hybrid-architectures and electromagnetic properties. This work reveals the mechanism of polarization-related dielectric relaxation of RGO, which provides new opportunities for designing the lightweight and highly efficient microwave absorbing materials by fully utilizing the hetero-interfacial effects. Keywords: reduced graphene oxide; iron-nickel; heterointerfaces; polarization and dielectric loss; microwave absorption