Interfaces between Charged Surfaces and Ionic Liquids: Insights from Molecular Simulations

Interfacial effects in (room temperature) ionic liquids at charged surfaces are very important for ionic liquids applications in electrochemistry,1 energy storage,2 catalysis3 and other areas (e.g., lubrication4,5). However despite the many articles published on this subject (several hundred papers just in 2013) there is still no general agreement in the literature about the main factors that govern the structure and properties of ionic liquids at charged interfaces. This is mainly due to a large number of available combinations of ionic liquids (and their mixtures) and different surfaces. In this article, we make an attempt to rationalize recent experimental and computational findings on structural transitions in ionic liquids at charged interfaces. Herein, we present a critical (qualitative) analysis of available molecular modeling and experimental data using a recently developed concept of surface charge compensation that allows one to compare results for different ionic liquids on the same methodological footing.6