The peculiar effect of water on ionic liquids and deep eutectic solvents

摘要: Ionic liquids (ILs) and deep eutectic solvents (DESs) have been suggested as eco-friendly alternatives to organic solvents. A trace amount of water is often unavoidable impurity, also added on purpose reduce their problematically high viscosity lower price. Understanding the distinct effects properties ILs/DESs highly important. In this review, we collect published experimental theoretical results for IL/DES–H2O systems at varied concentrations analyze them. Results from mechanistic studies, thermodynamic modelling advanced experiments are collected critically discussed. Six commonly studied were selected map observations onto microscopic obtained in studies. great variety contours excess can be observed over entire compositional range, indicating that unpredictable. Mechanistic studies clearly demonstrate H2O rapidly changes heterogeneous 3D structures pure ILs/DESs, leading very different behaviour. There similarities between aqueous electrolytes IL/DES solutions but bulky asymmetric cations do not conform standard salt dissolution hydration concepts. Thermodynamic previously assumes either a neutral ion-pair or completely dissociated ions, neglecting specific ion effects. new conceptual framework binary enable technologies practical applications.