Emma I. Rogers, D. Silvester, L. Aldous
Mar 24, 2008
Citations
0
Influential Citations
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Journal
Journal of Physical Chemistry C
Abstract
The electrochemical oxidation of 1-butyl-3-methylimidazolium iodide, [C4mim]I, has been investigated by cyclic voltammetry at a platinum microelectrode at varying concentrations in the RTIL 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [C4mim][NTf2]. Two oxidation peaks were observed. The first peak is assigned to the oxidation of iodide to triiodide, in an overall two-electron process: 3I- − 2e- → I3-. At higher potentials, the electrogenerated triiodide oxidizes to iodine, in an overall one-electron process: I3- − e- → 3/2I2. An average diffusion coefficient, D, for I- of 1.55 × 10-11 m2 s-1 was obtained. A digital simulation program was used to simulate the voltammetric response, and kinetic parameters were successfully extracted. The parameters deduced from the simulation include D for I-, I3-, and I2 and Keq,2, the equilibrium constant for the reaction of iodide and iodine to form triiodide. Values for these parameters are of the same order as those previously published for the oxi...