Three-dimensional printing of a tunable graphene-based elastomer for strain sensors with ultrahigh sensitivity

A graphene-based elastomer for sensors with tunable and high sensitivity was fabricated by using three-dimensional printing, in which a printable ink was developed by homogenizing graphene and polydimethylsiloxane (PDMS). To make the elastomer tunable and highly sensitive, different microstructures of three-dimensional graphene-PDMS (3DGP) can be formed. Attributed to its well-interconnected scaffolds and designed microstructures, 3DGP demonstrates a series of multifunctional properties, such as excellent stability and a large gauge factor (up to 448 at 30% strain). 3DGP has continuously stable piezoresistive behavior, even after 100 compress-release cycles under 10% strain. By considering the essential properties of 3DGP scaffolds, such as filament diameter, interaxial angle and interlayer space, the printed 3DGP structure can be tunable and highly sensitive. The controllable design and scalable fabrication of the 3DGP advanced functional material suggests that tunable strain sensors and wearable devices have great potential for different applications, which is a finding that can be referenced by future studies on 3D graphene-based sensors.