N-doped reduced graphene oxide-PEDOT nanocomposites for implementation of a flexible wideband antenna for wearable wireless communication applications

Abstract

We report a flexible and highly efficient wideband slot antenna based on a highly conductive composite of poly(3,4-ethylenedioxythiophene) (PEDOT) and N-doped reduced graphene oxide (N-doped rGO) for wearable applications. The high conductivity of this hybrid material with low sheet resistance of 0.56 Ω/square, substantial thickness of 55 μm, and excellent mechanical resilience (<5.5% resistance change after 1000 bending cycles) confirmed this composite to be a suitable antenna conductor. The antenna achieved an estimated conduction efficiency close to 80% over a bandwidth from 3 to 8 GHz. Moreover, the successful operation of a realized antenna prototype has been demonstrated in free space and as part of a wearable camera system. The read range of the system was measured to be 271.2 m, which is 23 m longer than that of the original monopole antennas provided by the supplier. The synergistic effects between the dual conjugated structures of N-doped rGO and PEDOT in a single composite with fine distribution and interfacial interactions are critical to the demonstrated material performance. The N-doped rGO sheet reinforces the mechanical stability whereas the PEDOT functions as additive and/or binder, leading to an improved electrical and mechanical performance compared to that of the graphene and PEDOT alone. This high-performing nanocomposite material meets requirements for antenna design and opens the door for diverse future non-metallic flexible electronic device developments. © 2021 IOP Publishing Ltd.