A review on electrodes modified with ionic liquids

Since 2000, ionic liquids are applied for electrode modification. Until the middle of 2010, almost 300 papers about ionic liquid-modified electrodes were published and they are reviewed here. Hydrophobicity, high viscosity, ionic structure, ionic conductivity, very low volatility and biocompatibility are among the properties of ionic liquids making them attractive for electrode modification. From the point of view of their structure, ionic liquid-modified electrodes range from electrode substrates covered by ionic liquid film or droplet(s) to the more complex film consisting of few components including ionic liquid. Bulk-modified electrodes as carbon paste electrodes with ionic liquid as binder and carbon nanotubes – gel electrodes represent another two classes of reviewed electrodes. Electrodes modified with appended ionic liquid form the last group. Initially, research on ionic liquid-modified electrodes was oriented towards fundamental studies of ion transfer across ionic liquid/aqueous solution interface. Now, almost entire research effort in this area is oriented towards their application for electrochemical sensing with multicomponent films and carbon paste electrodes being most popular.