Preparation of CoFe@N-doped C/rGO composites derived from CoFe Prussian blue analogues for efficient microwave absorption

Abstract

At present, in order to solve the problem of microwave radiation and interference, it is urgent to study high performance microwave absorption (MA) materials with strong absorption ability, light weight, thin thickness and broad bandwidth. In this work, CoFe@nitrogen-doped carbon/rGO (CoFe@NC/rGO) composites derived from CoFe Prussian blue analogues were successfully prepared by in situ growth and annealing. And the effects of GO content on the MA performances of the composites were studied systematically. Results reveal that MA properties of CoFe@NC/rGO composites are enhanced by introduction of GO, this is mainly because the addition of GO can provide large specific surface area for microwave reflection, enhance interfacial polarization and compensate the insufficient dielectric loss. Moreover, impedance matching, conduction loss and attenuation ability are also improved obviously. CoFe@NC/rGO composites show outstanding MA capability, and the minimum reflection loss is up to −53.0 dB at a thickness of 2.4 mm, the largest effective absorption bandwidth can achieve 4.48 GHz at a thin thickness of 1.7 mm. In consideration of the superior MA performances, the CoFe@NC/rGO composites will be ideal candidates for high-efficient MA applications.