A high performance and flexible in-plane asymmetric micro-supercapacitor (MSC) fabricated with functional electrochemical-exfoliated graphene

With the increasing development of miniaturized, integrated, wearable and portable electric devices, in-plane micro-supercapacitors (MSCs), as one of mast potential next-generation energy storage setups, have attracted abundant interests form the public. In this study, a flexible in-plane asymmetric MSC, prepared by the mask-assisted vacuum filtration, was demonstrated. Furthermore, the electrochemical-exfoliated functional graphene oxide (FGO) and chemical-reduced functional reduced graphene oxide (FrGO) were configured as positive and negative electrode of the MSCs, coated with the solid PVA/Na2SO4 electrolyte. The result presented that the as-assembled FGO-FrGO MSCs performed the highest areal capacitance of 7.3 mF cm(-2). It was assumed that the high performance of the asymmetric MSCs was attributed to the asymmetric in-plane interdigitated structure, the abundant functional groups doping and heteroatoms replacement with N, O, P, S elements in graphene. In summary, the functional graphene-based asymmetric MSCs provide a potential inspiration for the next-generation flexible and wearable energy storage devices. (C) 2020 Elsevier B.V. All rights reserved.