Direct Writing of Liquid Metal onto an Electrospun Graphene Oxide Composite Polymer Nanofiber Membrane for Robust and Stretchable Electrodes

Abstract

AbstractHighly stretchable electrodes with electrically robust behavior are critical for wide applications of soft robots, electronic skins, and flexible sensors. However, it remains challenging to fabricate such electrodes with traditional fabrication methods, such as lithography, conductive composite material synthetization, stencil printing, and microchannel injection. Herein, a facile method is proposed to construct robust and stretchable electrodes by direct‐written liquid metal (LM) onto a predeposited interface bonding layer, which greatly improves the interfacial force between the LM and substrate. An electrospun graphene oxide/thermoplastic polyurethane composite nanofiber membrane is used as the bonding layer, which provides rich –OH on the interface and in situ forming of hydrogen bond (H‐bond) with the LM oxide layer. A prototype electrode shows stretchability of 580%. The resistance remains stable that varies from 2.8 to 19.3 Ω at 500% elongation, and varies slightly after 7500 stretching cycles under 50% elongation, from 2.6–4.0 to 4.4–6.4 Ω. The fabrication technique is demonstrated with applications in stretchable circuit board assemblies and stretchable electronic cables, indicating a potential effective method for fabricating high‐performance stretchable electrodes.