Solid-liquid interfacial nanostructure of ionic liquids and deep eutectic solvents

Neoteric solvents such as ionic liquids and deep eutectic solvents have many potential applications in numerous fields, from drug delivery to catalysis. However, to optimize these solvents for specific applications, their nanostructure, in particular at the interface, must be understood. The following chapter summarizes our current understanding of ionic liquid- and deep eutectic solvent-interfacial nanostructure, with a particular focus on the solid interface. The techniques used to explore interfacial nanostructure are also discussed, with the advantages and disadvantages of each highlighted. Ultimately both ionic liquids and deep eutectic solvents exhibit strong nanostructure, both in the bulk and at the interface. However, this nanostructure is influenced by the solvent components, and their particular interactions, as well as by the specific substrate and its surface charge. Thus, the solid–liquid interfacial nanostructure of neoteric solvents is complex, and as this chapter highlights, requires further research.