Impacts of C60-Ionic Liquids (ILs) Interactions and IL Alkyl Chain Length on C60 Dispersion Behavior: Insights at the Molecular Level

Mechanisms underlying the impacts of interactions between carbon nanoparticles (CNPs) and ionic liquids (ILs) on the physicochemical behavior of CNPs need to be more full worked out. This manuscript describes a theoretical investigation at multiple levels on the interactions of fullerene C60 with 21 imidazolium-based ILs of varying alkyl side chain lengths and anionic types and their impacts on C60 dispersion behavior. Results show that π-cation interaction contributed to mechanism of the C60-IL interaction more than π-anion interaction. The calculated interaction energy (EINT) indicates that C60 can form stable complex with each IL molecule. Moreover, the direction of charge transfer occurred from IL to C60 during the C60-IL interaction. Quantitative models were developed to evaluate the self-diffusion coefficient of C60 (Dfullerene) in bulk ILs. Three interpretative molecular descriptors (heat of formation, EINT, and charge) that describe the C60-IL interactions and the alkyl side chain length were found to be determinants affecting Dfullerene