(484c) Molecular Simulation Study of the Dynamics of Ionic Liquid (IL) 1-n-Butyl-3-Methyl-Imidazolium-Bis(trifluoromethanesulfonyl)Imide [Bmim][NTf2] Confined in Graphite Slit Pore

Ionic liquids (ILs) are salts with melting temperatures below 100 °C. They are usually made
up of unsymmetrical organic cation and charge delocalized anion. ILs exhibit properties such
as negligible vapor pressure, excellent solvation ability, high thermal and electrochemical
stability, and good ionic conductivity, which make them viable for broad range of applications
as in solar cells, gas separations, and catalysis. The viscosity of bulk ILs are, however, usually
high which presents challenges when ILs are used in such applications. The high viscosity
is generally attributed to the strong intermolecular forces in ILs. We explore, in this study, if
nanoconfinement of ILs leads to decrease in viscosity. To this end, a molecular simulation study
is performed to examine the effect confinement has on the dynamics of the ionic liquid (IL) 1-
n-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide [bmim][NTf2] at different
temperatures. Self-diffusion coefficients and activation energies are reported, and compared
with results obtained for the bulk IL. We also analyze the dynamics of the IL as a function of
the distance of ions from the pore wall. Additionally, the velocity auto correlation function,
rotational correlation function and van Hove correlation functions are presented in order to
provide a detailed perspective on the dynamics of the system.