In situ twisting for stabilizing and toughening conductive graphene yarns

Graphene fibres are of great interest for diverse applications such as their use in supercapacitors, batteries, stimulus-responsive actuators and smart textiles. However, previously reported graphene-based fibres commonly have very low toughness and poor stretchability, which can limit many of their possible applications. We demonstrate an efficient approach for preparing super-tough yarns of reduced graphene oxides via the in situ twisting of multiplied graphene oxide fibres during fibre extrusion and coagulation, followed by chemical reduction and drying. These twisted multiplied yarns have a toughness of 46.3 J m^-3, much higher than previous results for graphene-based fibres and films, and benefit from the retention of high strength and a significant increase in the failure strain due to the stably twisted hollow structure of the yarns. These yarns also show very stable electrical resistance when subjected to cyclic stretching at a large tensile strain. We demonstrate the utilization of such yarns for stretchable conducting electronic wires.