The behavior of nanodroplets formed by amino acid based 1-ethyl-3-methylimidazolium glycine ionic liquid on graphene sheets was studied using classic molecular dynamics. Nanodroplets of different sizes were analyzed, and the contact angle was inferred. The ion–graphene interaction energy was calculated as a function of droplets size, together with the ions arrangement at the interface. Likewise, wetting of SiO2 and graphene supported on SiO2 by ionic liquid nanodroplets was also analyzed. Graphene wetting by this ionic liquid is discussed in terms of the changes on fluid structure upon adsorption and the mechanism and strength of ion–graphene interactions.

Excess viscosities, excess volumes, and free energies of activation for viscous flow of the binary mixtures 2-pyrrolldone + methanol, + ethanol, + 1-propanol, + 1-butanol, and + 1-pentanol were calculated at five different temperatures from density and viscosity measurements. The results obtained suggest that the breaking of the self-associations existing In the pure liquids Is partly balanced by the heteroassociations formed among the molecules of the binary mixtures. These heteroassociations decrease with decreasing temperature and Increasing chain length of the alcohol. The small excess volumes calculated denote weak Interactions, In accordance with the different shape and size of the mixing molecules.

Quantum chemistry methods were used to analyze the properties of ionic pairs formed by combination of the 1-ethyl-3-methylimidazolium cation with anions derived from alanine, glycine, serine, and phenylalanine amino acids, which appear in the corresponding ionic liquids. Anion−cation pairs were studied from structural and energetic viewpoints using density functional theory together with the use of natural bond orbital and atoms in a molecule approaches. Interactions of the mentioned ionic pairs with carbon nanostructures carried out with graphene sheets and single-walled carbon nanotubes, with ions placed on the outer surface and when confined inside the nanotube, were analyzed from first principles. Interaction energies, density of states, and charge density allow inferring the mechanism of interaction between the ion pairs and graphene or carbon nanotubes.

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The properties of 1-ethyl-3-methylimidazolium glycinate ionic liquid regarding fullerenes, graphene, and single-walled carbon nanotubes are studied using classical molecular dynamics simulations. Endohedral fullerenes forming C60 to C540 containing a variable number of confined ions are studied, and the solvation of these systems by bulk liquid phases is also studied. The adsorption of the ionic liquid on top of graphene sheets and the confinement between two sheets are also analyzed as a function of intersheet separation. Likewise, confinement inside single-walled nanotubes as a function of nanotube diameter is analyzed together with ionic mobility in comparison with bulk phases. External solvation, densification, and layering around the nanotubes are also considered. The properties of these systems involving amino acid-based ionic liquids are compared with available studies involving classical imidazolium ionic liquids with other types of ions.