Fused coarse-grained model of aromatic ionic liquids and their behaviour at electrodes

Abstract

A fused coarse-grained model of aromatic ionic liquids 1-alkyl-3-methylimidazoliums tetrafluorob-]) has been constructed. Structural and dynamical properties calculated from our model are compared with experimental data as well as with corresponding results from simulations of other suggested models. Specifically, we adopt a fused-sphere coarse-grained model for cations and anions. This model is utilized to study structure and differential capacitance in models of flat and porous carbon electrodes. We find that the capacitance varies with pore size, in a manner that is related to the packing of ions inside the pore. For very narrow pores, diffusion is slow and the establishment of thermodynamic equilibrium may exceed the practical limits for our Molecular Dynamics simulations.

The Effect of Phenyl Substitutions on Microstructures and Dynamics of Tetraalkylphosphonium Bis(trifluoro‐ methylsulfonyl)imide Ionic Liquids

“…ILs have received significant attention in diverse academic and industrial communities due to their multifaceted physicochemical properties, such as non‐flammability, negligible volatilities, reasonable viscosity‐temperature characters, high thermal‐oxidative stabilities, wide electrochemical windows, as well as excellent affinities to polar and apolar compounds . These fascinating characteristics render ILs exceptionally attractive and reliable alternatives to conventional molecular liquids in applications ranging from material synthesis and catalysis to gas absorption and separation (as solvents and membrane transport media), as well as electrochemistry …”

4. Multigranular modeling of ionic liquids

“…The local ionic environment is characterized by loose micelle-like aggregates in a highly branched water network. Either ILs used as lubricants between sliding contacts in tribology [12,14,15,32,33], as electrolytes in electrochemical energy devices [1,7,12,16,17,21,29,31,71,87] or as liquid absorbents for CO 2 capture from fossil-fuel burning power plants [12,13,19,20,28], a common feature is the presence of interfaces between ILs and solid, gas phases [1, 7, 12-17, 19, 20, 26, 28-30, 32, 71, 87-93]. Experimental investigations of ILs under confinement indicate that physicochemical properties (melting points, surface tensions, chemical reactivities, etc.)…”

“…This physical picture can qualitatively explain the experimentally observed IL crystal structure, the transition from IL to isotropic liquid crystal and changes in physicochemical and structural properties of ILs with varied aliphatic chains. In subsequent work, several coarse-graining schemes were proposed for imidazolium cations [31,41,55,134]. Interaction potentials between CG beads are either obtained from specific coarse-graining approaches, like iterative Boltzmann inversion (IBI) method [134], or described by generic interaction potentials [55].…”

Force field of tetrafluoroborate anion for molecular dynamics simulation: a new approach

“…Several approaches of modeling tetrafluoroborate anion were found in the literature: "coarse grain" (CG) models [9][10][11], polarizable models [9,12], rigid models [13][14][15][16], all-atom soft models [17][18][19][20][21][22][23][24][25][26].…”