Probing the Electroresponsivity of Segregated Aqueous Nanodomains in Ionic Liquid Matrices

Recent research has highlighted that many fluids with high ionic strength, such as ionic liquids (ILs), display a maximum water uptake prior to transitioning to simple aqueous solution behaviour. Heterogeneous aggregates are known to form in ILs, with segregation of the apolar components and polar domains, which form 'clusters'. Small amounts of added water tend to be limited to these polar domains, sometimes forming water channels, which are evident by 1H-NMR, where the water peaks of 'bound' water are shifted significantly compared to ‘free’ water. Our studies provide evidence that the anion identity is the major driver for the type and strength of interactions between the IL and water. Here we propose a study of the heterogeneous structures formed between water and 2 different 1-ethyl-3-methylimidazolium (emim) ILs with different anions, using diffraction ideally on NIMROD. We will obtain isotopically labelled ILs for measurement from the deuteration facility. We plan to use a flat plate silica/PEEK electrochemical cell with a potentiostat to make exploratory measurements into the electroresponse of our ILs at a series of applied potentials, particularly in the 'zone of maximum conductance', where small quantities of added H2O/D2O act as structural plasticisers.