@article{boxall_osteryoung_2004, title={Switching potentials and conductivity of polypyrrole films prepared in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate}, volume={151}, ISSN={["1945-7111"]}, DOI={10.1149/1.1634275}, abstractNote={Polypyrrole (ppy) and poly(N-methylpyrrole) (pmpy) films were prepared galvanostatically at the ring of a rotating ring-disk electrode from the corresponding monomers dissolved in the ionic liquid 1-butyl-3-methylimidazolium hexafluorophosphate (bmimPF 6 ) Rotating ring-disk voltammetry was used to determine switching potentials and conductivity of the films while immersed in bmitnPF 6 . Switching potentials of 0.63 ± 0.04 and 1.07 ± 0.03 V vs. the cobaltocenium/cobaltocene couple, [CoCp 2 ] +/0 , were determined for the ppy and pmpy films, respectively, from negative potential scan voltammograms. Positive potential scan voltammetry was used to obtain the potential-dependent conductivity of the films as the films switched from their insulating (at potentials more negative than switching potential) to a quasi-metallic state. Two different computational models (nonlinear vs. linear conductance gradients) and two different redox probes ([CoCp 2 ] +/0 and decamethylferrocenium/ decamethylferrocene) were used in the calculation of the film conductivity. The conductivity of the ppy films increased by an order of magnitude for every 72 ± 8 mV change in the applied potential. At potentials less than the switching potential, the conductivity of the pmpy films increased tenfold for every 110 ± 15 mV change in the applied potential. At potentials greater than the of teh pmpy films the pmpy films required a 200 mV change to induce the same degree of change in film conductivity.}, number={2}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Boxall, DL and Osteryoung, RA}, year={2004}, month={Feb}, pages={E41–E45} }
 @article{boxall_jj o'dea_osteryoung_2002, title={Apparent anomaly during rotating disk voltammetry in ionic liquids}, volume={149}, ISSN={["1945-7111"]}, DOI={10.1149/1.1514647}, abstractNote={An apparent anomaly is described in which maxima on rotating disk voltammograms for ferrocene oxidation in an ionic liquid were found. The ionic liquid, 1-butyl-3-methylimidazolium hexafluorophosphate, bmimPF 6 , is a neoteric solvent of current interest. The maxima are shown to he due to the very high viscosity of the solvent, 3.26 poise, which yields an unusually high Schmidt number (Sc) of 3.5 × 10 7 , compared to a value of about 10 3 for aqueous solutions. It is estimated that over 100 revolutions of the disk are needed to achieve the Levich limiting current following application of a voltage step to the disk. The current transient resulting from application of a voltage step to the rotating disk is found to be in agreement with previously developed theory, even for these highly viscous systems. Analysis of the transient permits a determination of Sc values without measurement of the viscosity and density of the solvent, or diffusion coefficient of the reacting species.}, number={11}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Boxall, DL and JJ O'Dea and Osteryoung, RA}, year={2002}, month={Nov}, pages={E468–E471} }
 @article{boxall_osteryoung_2002, title={Electrochemical properties of alkali metals in 1-butyl-3-methylimidazolium hexafluorophosphate}, volume={149}, ISSN={["0013-4651"]}, DOI={10.1149/1.1473191}, abstractNote={Formal potentials and diffusion coefficients of the alkali metal couples of lithium, sodium, and potassium hexafluorophosphate salts dissolved in 1-butyl-3-methylimidazolium hexafluorophosphate were determined using a hanging mercury drop electrode as the working electrode. Chronoamperometry was used to determine the diffusion coefficients, which ranged from 1.4 X 10 -8 to 4.5 × 10 -8 cm 2 /s for the Na and K cations, respectively. Formal reduction potentials of -2.96 ± 0.01 V and -3.35 ± 0.01 V vs. the ferrocene/ferrocenium couple were obtained for sodium and potassium using normal pulse voltammetry. The presence of adsorption maxima in the lithium normal pulse voltammograms necessitated the use of chronopotentiometry to determine a lithium formal potential of -2.45 ± 0.02 V.}, number={6}, journal={JOURNAL OF THE ELECTROCHEMICAL SOCIETY}, author={Boxall, DL and Osteryoung, RA}, year={2002}, month={Jun}, pages={E185–E188} }