The interfacial structuring of a non-halogenated ionic liquid (IL) will be studied at a gold electrode interface as a function of applied potential, bulk IL concentration and water content. For enhanced sensitivity to changes in the interfacial layers, the scattering length density of the IL mixtures (with propylene carbonate) will be contrast matched to that of the gold. The results will be compared to recent neutron reflectivity (NR) measurements for another IL with the same cation, but a larger, more hydrophobic anion. Complementary atomistic simulations and tribological measurements by our group suggest a significantly different interaction for these two anions and water, thus affecting their lubrication properties. By integration of such knowledge with NR we hope to guide the future application of ILs as ‘tribotronic’ lubricants, as well as in other electrochemical applications.