| Summary: | A gold electrode was derivatized by electrochemical reduction of anthraquinone-2-diazonium tetrafluoroborate (AQ2-N 2+BF 4-) giving an Au-AQ2 modified electrode of a surface coverage below a monolayer. Simulations of cyclic voltammograms using Marcus-Hush-Chidsey theory for 2e - process and assuming a uniform surface were not able to achieve a good fit for the overall shape of the baseline subtracted experimental voltammograms. Subsequently two models of surface inhomogeneity based on Marcus-Hush-Chidsey theory were investigated: a distribution of formal potentials, E o′, and a distribution of electron tunneling distances, r 0. The simulation of cyclic voltammograms involving the distribution of formal potentials allowed a good agreement between theory and experiment. The parameters of the Au-AQ2/Au-AQ2 2- process compared to the parameters of the EPPG-AQ2/EPPG-AQ2 2- process reported previously by Kozub et al. (ChemPhysChem, 12 (2011) 2806) show much faster kinetics, attributed to the higher density of electronic states for a gold electrode. © 2011 by ESG.
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