Cabbage-like flexible fluororubber/carbon aerogel hybrids with negative Poisson’s ratios and excellent microwave absorption

Carbon aerogels have excellent heat resistance and electrical conductivity, but their poor structural integrity significantly limits their applications. We design a stable carbon nanotube (CNT)/graphene oxide (GO)-based carbon aerogel with a "cabbage-like" structure that is created through initial hydrogel formation via hydrothermal annular convection to realize the self-assembly of GO nanosheets and CNTs, followed by freeze drying of the hydrogel. The formed carbon aerogel is subsequently modified by a fluororubber solution to achieve both physical coating and hydrogen bonding between the thin fluororubber film and the aerogel. Thanks to the unique cabbage-like architecture and porous structure stabilized and protected by the fluororubber film, the resultant fluororubber/carbon aerogel (FCGA) hybrids possess unique mechanical properties, including negative Poisson's ratios during compression and superior compressibility. Besides, FCGA hybrids have a low thermal conductivity, outstanding fire resistance, and exceptional microwave-absorption performance. Therefore, FCGA hybrids are promising for applications in flexible/wearable electronics, microwave absorption, etc.