Superelastic\nCarbon Aerogel with Ultrahigh and Wide-Range\nLinear Sensitivity

Abstract

Compressible\nand elastic carbon materials offer many advantages\nand have promising applications in various electronic devices. However,\nfabricating carbon materials with super elasticity, fatigue resistance,\nand high and wide-range linear sensitivity for pressure or strain\nremains a great challenge. Herein, a facile and sustainable route\nis developed to fabricate a carbon aerogel with not only superior\nmechanical performances but also exceptionally high and wide-range\nlinear sensitivity by using chitosan as a renewable carbon source\nand cellulose nanocrystal as a nanoreinforcement or support. The as-prepared\ncarbon aerogel with wave-shaped layers shows high compressibility,\nsuper elasticity, stable strain–current response, and excellent\nfatigue resistance (94% height retention after 50 000 cycles).\nMore importantly, it demonstrates both an ultrahigh sensitivity of\n103.5 kPa^–1 and a very wide linear range of 0–18\nkPa. In addition, the carbon aerogel has a very low detection limit\n(1.0 Pa for pressure and 0.05% for strain). The carbon aerogel also\ncan be bended to detect a small angle change. These superiorities\nrender its applications in various wearable devices.