Super-stretchable and negative-Poisson-ratio meta-aerogels

Abstract

Highly stretchable aerogels are promising for flexible electronics but their fabrication is a great challenge. Herein, several kinds of unprecedented intrinsically super-stretchable conductive aerogels with low or negative Poisson’s ratios are achieved by uniaxial, biaxial, and triaxial hot-pressing strategies. The highly elastic reduced graphene oxide/polymer nanocomposite aerogels with folded porous structures obtained by uniaxial hot pressing exhibit record-high stretchability up to 1200% strain, significantly surpassing all those of the reported intrinsically stretchable aerogels. Furthermore, the never-before-realized meta-aerogels with reentrant porous structures combining high biaxial (or triaxial) stretchability and negative Poisson’s ratios have been achieved by biaxial (or triaxial) hot pressing. The resulting aerogel-based wearable strain sensors exhibit a record-wide response range (0-1200%). In addition, they can be applied for smart thermal management and electromagnetic interference shielding, which are achieved by regulating the porous microstructures via stretching. This work provides a versatile strategy to highly stretchable and negative-Poisson-ratio porous materials promising for various applications including but not limited to flexible electronics, thermal management, electromagnetic shielding, and energy storage.