title: Combining impedance spectroscopy with cyclic voltammetry: measurement and analysis of kinetic parameters for faradaic and nonfaradaic reactions on thin-film gold.
abstract: The technique of time-resolved impedance spectroscopy can be combined with dc cyclic voltammetry (CV) to study mechanisms and kinetics of electrochemical reactions at solid-liquid interfaces. Utilization of these techniques in a combined framework, however, is based on a number of specific considerations of measurement procedures and data analysis. The present work discusses certain essential elements of this topic, focusing primarily on the analysis of time-resolved impedance spectra where interdependent dc and ac effects of parallel faradaic and nonfaradaic reactions are present under potentiodynamic conditions. A thin gold film is used as a model experimental system where oxidation and reduction of the sample surface is voltage-controlled both in the presence and in the absence of specifically adsorbing Cl- ions in neutral background electrolytes of NaF. Impedance spectra are recorded under transient conditions of CV, and kinetic parameters based on electrode-equivalent circuit models are obtained as functions of CV scans.
authors.affiliation: Department of Physics, Clarkson University, Potsdam, New York 13699-5820, USA.
authors.forename: C M
authors.initials: CM
authors.lastname: Pettit
authors.forename: P C
authors.initials: PC
authors.lastname: Goonetilleke
authors.forename: C M
authors.initials: CM
authors.lastname: Sulyma
authors.forename: D
authors.initials: D
authors.lastname: Roy
mesh_terms: D006046:Gold / Q000737:chemistry*; D007700:Kinetics; D010084:Oxidation-Reduction; D013057:Spectrum Analysis
chemical_list: D006046:Gold