Fast Ion Transfer Associated with Dehydration and Modulation of Hydration Structure in Electric Double-Layer Capacitors Using Molecular Dynamics Simulations and Experiments

Carbon materials, such as graphite and activated carbon, have been widely used electrodes in batteries electric double-layer capacitors (EDLCs). Graphene, which has an extremely thin sheet-like structure, is considered a fundamental carbon material. However, it was less investigated electrode material than carbons. This because graphene relatively new difficult to handle. using can enhance the performance of nanodevices. Here, EDLCs based on single-layer bilayer LiCl, NaCl, KCl aqueous electrolyte solutions evaluated cyclic voltammetry, charging mechanism molecular dynamics simulations. solution provided highest capacitance compared LiCl NaCl case electrodes. In contrast, dependence ion species hardly observed graphene. indicates that Li Na ions also contributed capacitances. The high EDLC be attributed fast transfer promoted by dehydration modification second hydration shell strong interaction with