An atomistic physico-chemical description of acetonitrile/tricyanomethanide based electrolytes

The development of high-performance electrolytes is of paramount importance to the energy storage area. In recent years, experimental and computational works on the 1-butyl-3-methylimidazolium tricyanomethanide, [EMIM][C(CN)(3)], have been shown that this ionic liquid and its organic liquids solutions may be suitable for use as electrolytes in supercapacitors. In this work, atomistic molecular dynamics simulations are used to obtain a detailed description of structural, dynamic, thermodynamic and electrostatic properties of [EMIM][C(CN)(3)]/acetonitrile mixtures. Our simulated results for cohesive energy and diffusion coefficient corroborate the higher ionic mobility which is associated with the low viscosity of this electrolyte. All simulations performed here indicate that both liquids are mutually miscible, with no evidence of aggregate formation, which could affect their conductive properties. Finally, calculations of capacitive electrostatic properties on a graphene electrolytic cell indicate that the liquid has relatively high electrode capacitance with high asymmetry. (C) 2019 Elsevier B.V. All rights reserved.