Electrochemical Characterization of Iodide Ions Adsorption Kinetics at Bi(111) Electrode from Three-Component Ionic Liquids Mixtures

The electrochemical behavior of RTIL mixtures containing 1-ethyl-3-methylimidazolium tetrafluoroborate, 1-ethyl-3methylimidazolium trifluoromethanesulfonate and 1-ethyl-3-methylimidazolium iodide were characterized by using cyclic voltammetry and electrochemical impedance spectroscopy methods. The capacitance values of the system at potentials more positive than −0.6 V (vs. Ag|AgCl| mixture of RTIL) strongly depend on the chemical nature of the anions in the mixture. Also the strong adsorption of I− at Bi(111) (well-known in aqueous and classical organic solvents) has been demonstrated in RTIL media. The capacitance values are noticeably higher for EMImOTF + EMImBF4 + 1 wt% EMImI than that for EMImOTF + 1 wt% EMImI. © The Author(s) 2015. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited. [DOI: 10.1149/2.0011512eel] All rights reserved.