Aramid nanofiber framework supporting graphene nanoplate via wet-spinning for a high-performance filament

Graphene-based filaments or yarns offering outstanding electrically-conductive and lightweight advantages are competitive candidates for flexible wires. The challenge is that low-oxidizing graphene tend to aggregate due to strong interaction among sheets, and it is difficult to assemble graphene into filaments. At present, even though diverse strategies are introduced to ameliorate graphene dispersibility and fabricability, their technological processes are often intricate and the corresponding fibers are severely flimsy. Herein, aramid nanofibers (ANFs) with excellent nanoscale dispersity and mechanical property are chosen as an auxiliary to support graphene nanoplates (GNPs) by non-covalent interactions and electrostatic repulsive-force in solvent. Moreover, a one-step process via simple wet-spinning is presented to fabricate GNPs/ANFs wires directly. The resultant GNPs/ANFs wire with a weight ratio of 80/20 demonstrates a high conductivity of 4236 S/m and tensile strength of 227.5 MPa with 10.2% elongation simultaneously. Even more, benefiting from the introduction of ANFs framework, the hybrid fibers not only have superior durability but also withstand burning and high temperature exceeding 400 °C. This work provides a strategy for the assembly of a novel flexible wire, which is facile for mass production and has a potential value for wearable devices.