Molecular dynamics study of confined ionic liquids in Au nanopore

Molecular dynamics simulations were carried to investigate the structure and dynamics of [BMIM][PF6] ionic liquid (IL) confined inside a slit-like Au metal nanopore with a pore size of 5.0 nm. The calculations show that the mass and number densities of the confined ILs are oscillatory; the solid-like high density layers are formed in the vicinity of the metal surface. The orientational investigation shows that the imidazolium ring of [BMIM] cations prefers to form a small tilt angle with the pore walls. Furthermore, the mean squared displacement (MSD) calculation indicates that the dynamics of confined ILs are remarkably slower than those observed in bulk systems. Our results suggest that the confinement of the Au nanopore can strongly affect the structural and dynamical properties of the confined ILs.