Investigating the asymmetry in the EDL response of C60/graphene supercapacitors

Abstract

Development of efficient electrodes is one of the main ways to increase the performance of an electrochemical energy storage device. It is known that such performance is associated with the electrode specific area, which allows a much larger interfacial interaction with the electrolyte. In this work, molecular dynamics is employed to model C60/graphene composite electrodes that can expand the effective area by approximately 70% relative to a pure graphene electrode. Our simulations indicate that the performance of supercapacitors of C60/graphene electrodes is superior to those made of planar graphene, in some cases up to 150%. The inherent electrolyte asymmetry in the investigated supercapacitors has a negative effect on the total capacitance, indicating that even better results could be obtained after rational design of the fullerene density on the surface of the graphene as well as the choice of the ions in the liquid ionic composition.