Choline chloride-acetic acid mixture as a medium for the investigation of the electrochemical processes

Abstract

Physicochemical properties of a liquid mixture containing choline chloride (ChCl) and acetic acid (AA) with a molar ratio of 1:2 were analyzed to determine its suitability for electrochemical studies. Viscosity, ionic conductivity, and density values as well as the width of the electrochemical window of the ChCl:AA mixture show that this liquid can be used as a supporting electrolyte in electrochemical studies. This was confirmed by the results of electrochemical studies on a model red-ox system of o-tolidine. Additional electrochemical tests revealed the dissolution of solid Pt in ChCl:FA. The ChCl:AA solution was also used as a background electrolyte in preliminary studies on the electrochemical reduction of pertechnetates. Cyclic voltammetry and UV-Vis spectroscopy experiments reveal a multi-path process which leads to the formation of Tc(IV or III) ionic species.