Simulations of the Structure and Dynamics of Nanoparticle-based Ionic Liquids
We use molecular dynamics simulations over microsecond time scales to study the structure and dynamics of coarse-grained models for nanoparticle-based ionic liquids. The systems of interest consist of particles with charged surface groups and linear or three-arm counterions, which also act as the solvent. A comparable uncharged model of nanoparticles with tethered chains is also studied. The pair correlation functions display a rich structure resulting from the packing of cores and chains, as well as electrostatic effects. Even though electrostatic interactions between oppositely charged ions at contact are much greater than the thermal energy, we find that chain dynamics at intermediate time scales are dominated by chain hopping between core particles. The uncharged core particles with tethered chains diffuse faster than the ionic core particles.
Abdullah University of Science and Technology (KAUST) and by grants DE-SC-
0002128 from the US Department of Energy, Office of Basic Energy Sciences and
CBET-1033155 from NSF. Simulations were performed on the Della cluster of
PICScIE, a facility supported by Princeton University. The authors would like to
thank Prof. Fernando Escobedo for suggesting the NOHMs model, and Prof. Emmanuel
Giannelis and Lynden Archer for many helpful discussions.