Imidazolium ionic liquid–water mixtures: The formation of a new species that inhibits the electrocatalytical charge transfer processes on a platinum surface

Cyclic voltammetry measurements using a platinum electrode were performed to study the effect of water when added to the imidazolium room-temperature ionic liquids (RTILs) 1 [C7O3MIm][Mes] and 2 [C3O1MIm][Mes]. The addition of a very small amount of water to RTIL 1 resulted in diminished cathodic current values. An even more pronounced effect was observed with RTIL 2 and all charge transfer processes were extremely reduced. This inhibition of the charge transfer processes suggests the formation of new species, due to a reaction between water and the RTILs, that adsorbs on the electrode surface.