Creep- and fatigue-resistant, rapid piezoresistive responses of elastomeric graphene-coated carbon nanotube aerogels over a wide pressure range

• Published in: Cellular polymers 2017-01, Vol.9 (3), p.1128-1135
• Main Authors: Tsui, Michelle N, Islam, Mohammad F
• Format: Article
• Language: English
• Subjects: Aerogels; Cold flow; Elastomers; Graphene; Lightweight; Mechanical properties; Nanotubes; Piezoresistivity; Single wall carbon nanotubes; Suspensions (Chemistry); Weight reduction
• ISSN: 2040-3364; 0262-4893; 2040-3372
• DOI: 10.1039/c6nr07432d

Lightweight, flexible piezoresistive materials with wide operational pressure ranges are in demand for applications such as human physical activity and health monitoring, robotics, and for functional interfacing between living systems and wearable electronics. Piezoresistivity of many elastomeric foams of polymers and carbon allotropes satisfies much of the required characteristics for these applications except creep and fatigue resistance due to their viscoelasticity, critically limiting the reliability and lifetime of integrated devices. We report the piezoresistive responses from aerogels of graphene-coated single-walled carbon nanotubes (SWCNTs), made using a facile and versatile sol-gel method. Graphene crosslinks the junctions of the underlying random network of SWCNTs, generating lightweight elastomeric aerogels with a mass density of ≈11 mg mL (volume fraction ≈7.7 × 10 ) and a Young's modulus of ≈0.4 MPa. The piezoresistivity of these aerogels spans wide compressive pressures up to at least 120 kPa with sensitivity that exhibit ultrafast temporal responses of