Well-ordered structure at ionic liquid/rutile (110) interface

The interface between the ionic liquid (IL) 1-butyl-3-methyl-imidazolium nitrate [BMIM+][NO3-]and the titanium dioxide rutile (110) surface is studied by classical molecular dynamics simulation. The simulation shows that the NO3- anions segregate on the surface and organize themselves into a highly ordered manner. The BMIM+ cations are found to occupy the region next to the absorbed NO3- layer, and the imidazolium (im) ring of the cation has a large tendency to slant with the im ring normal nearly perpendicular to the rutile (110) surface normal. The interfacial structure found in the current study may provide new insight to understand the double layer structure at the IL/solid interface.