Super-Elastic Graphene Ripples for Flexible Strain Sensors

TLDR

The study presents a buckling method to create graphene and graphene ribbon ripples on stretchable elastomeric substrates. Graphene is transferred onto prestrained PDMS films and, upon strain release, spontaneously forms nanoscale periodic buckles. The resulting graphene ripples exhibit morphology and periodicity governed by ribbon width and PDMS prestrain, enabling large strain deformation and demonstrating effective strain‑sensing capabilities with measurable resistance changes, thereby offering a simple, controllable fabrication route for flexible electronic devices.

Abstract

In this study, we report a buckling approach for graphene and graphene ribbons on stretchable elastomeric substrates. Stretched polydimethylsiloxane (PDMS) films with different prestrains were used to receive the transferred graphene, and nanoscale periodical buckling of graphene was spontaneously formed after strain release. The morphology and periodicity of the as-formed graphene ripples are dependent strongly on their original shapes and substrates' prestrains. Regular periodicity of the ripples preferred to form for narrow graphene ribbons, and both the amplitude and periodicity are reduced with the increase of prestrain on PDMS. The graphene ripples have the ability to afford large strain deformation, thus making it ideal for flexible electronic applications. It was demonstrated that both graphene ribbon and nanographene film ripples could be used for strain sensors, and their resistance changes upon different strains were studied. This simple and controllable process of buckled graphene provides a feasible fabrication for graphene flexible electronic devices and strain sensors due to its novel mechanical and electrical properties.