Preparation and microwave absorption performance of a flexible Fe3O4/nanocarbon hybrid buckypaper and its application in composite materials

Abstract

Graphene oxide (GO) and carbon nanotubes are promising microwave-absorbing materials. Herein, ferroferric oxide (Fe₃O₄)/multiwall carbon nanotube (MWCNT) and Fe₃O₄/GO hybrid buckypapers with excellent flexibility and manoeuvrability were coated on the surface of an epoxy substrate to fabricate microwave-absorbing composites. Fe₃O₄/GO buckypapers show a unique layered structure that differs from the complex network structure of Fe₃O₄/MWCNT buckypapers. Therefore, the Fe₃O₄/GO buckypapers exhibit lower tensile strength and toughness than the Fe₃O₄/MWCNT buckypapers, and the minimum electromagnetic reflection loss of Fe₃O₄/GO buckypapers is higher than that of Fe₃O₄/MWCNT buckypapers. Further, Fe₃O₄/GO buckypapers have a wider effective absorption-frequency band than Fe₃O₄/MWCNT buckypapers at 2.0–18.0 GHz. Although the mechanical properties of epoxy resin composites coated with Fe₃O₄/MWCNT or Fe₃O₄/GO buckypapers show a slight deterioration in comparison with those of the epoxy resin substrate, both buckypapers exhibit improved microwave-absorption performance compared with the epoxy resin substrate.