Dominant ion transport processes of ionic liquid electrolyte in poly(3,4-ethylenedioxythiophene)

Electrochemical quartz crystal microgravimetry was used to study movement of the ionic liquid 1‐ethyl‐3‐methylimidazolium bis(trifluoromethylsulfonyl)imide (EMIBTI) into and out of poly(3,4‐ethylenedioxythiophene) (PEDOT). In 0.1M EMIBTI/acetonitrile, anionic transport predominates, as is typical of solution‐based electrolytes. In pure EMIBTI, on the other hand, the minimal mass change observed during polymer oxidation/reduction was observed to be cation‐dominant. PEDOT deposition from dilute EMIBTI solution followed by cycling in neat EMIBTI resulted in rapid decrease of electroactivity. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2013 Electroactive polymers produced from ionic liquid electrolytes exhibit remarkable electrochemical stability. It has been shown that the choice of ion significantly affects transport properties. The ability to electropolymerize in a dilute solution of ionic liquid electrolyte and then perform polymer electrochemistry in neat ionic liquid electrolyte would minimize the amount of ionic liquid used during polymerization and significantly reduce cost and improve stability. Unfortunately, electroactivity decreases significantly.