Carbon Nanotube/Chitosan-Based Elastic Carbon Aerogel for Pressure Sensing

Elastic carbon materials with high compressibility are ideal candidates for flexible piezoresistive sensors. Carbon nanotubes (CNTs) are promising nanoblocks for fabricating compressible and elastic carbon aerogels because of their excellent conductivity and mechanical strength. However, insufficient interaction among CNTs makes them difficult to assemble in an elastic macrostructure. Herein, a facile yet effective method was proposed to fabricate a compressible and elastic carbon aerogel from multiwalled carbon nanotubes (MWCNTs) using chitosan as a binder. The biopolymer can link MWCNTs into continuous lamellas and lead to three-dimensional architectures with excellent structural stability. The carbon aerogel can withstand a high compression strain (90%) and exhibits excellent fatigue resistance, with only 8% plastic deformation after 50 000 cycles at 50% strain. It also shows a high resistance stability after 50 000 compression cycles and good sensitivity (4.45 kPa–1) and can detect human biological signals. Satisfactory mechanical and sensing properties enable its application in wearable piezoresistive sensors.