N-doped reduced graphene oxide aerogels containing pod-like N-doped carbon nanotubes and FeNi nanoparticles for electromagnetic wave absorption

Abstract

Lightweight and low filler loading of electromagnetic wave absorption materials remain a huge challenge under the premise of strong absorption and broad absorption band. Here, we offer a facile strategy to prepare the ultralight self-supported N-doped reduced graphene oxide aerogels containing pod-like N-doped carbon nanotubes and FeNi@N-doped graphene layer core-shell nanoparticles for high-performance electromagnetic wave absorbing materials. The mass density of the ultralight aerogels is 0.0131 g cm−3, greatly lower than those of activated carbons. With a filling loading of only 10 wt% and the matching thickness of 2.0 mm, the minimal reflection loss of aerogels reaches −39.39 dB at 13.28 GHz. When the matching thickness is smaller than 2.0 mm (1.6–2.0 mm), the minimal reflection loss values of the optimized aerogels can still exceed −20 dB superior to most of reported electromagnetic wave absorption counterparts. Moreover, its maximum effective absorption bandwidth is up to 4.7 GHz at the matching thickness of merely 1.8 mm. The excellent performance of the ultralight bimetal-based aerogels mainly derives from increased dielectric loss, better matching impedance and larger specific surface area. It could be believed our designed ultralight self-supported aerogels can be promising candidates for lightweight absorbers with strong attenuation abilities.