Simplifying mechanistic impedances
Date
2020
Authors
Harrington, David A.
Journal Title
Journal ISSN
Volume Title
Publisher
Electrochimica Acta
Abstract
Common simplifying concepts of chemical kinetics, such as rate-determining and preequilibium steps, can be used to simplify the formulation of the electrochemical impedance for reaction mechanisms. A general strategy for eliminating kinetic parameters of preequilibrium steps from the governing equations is presented, which enables simpler subsequent generation of the impedance spectra and associated equivalent circuits. Examples that are various subcases of a metal electrode with simultaneous hydrogen evolution and hydrogen adsorption into the metal are discussed. The relationship of the apparent charge-transfer resistance to the true charge-transfer resistance is discussed. Examples are given where the presence of adsorption is masked and may not be easily detected in an impedance analysis.
Description
Keywords
Rate-determining step, Equivalent circuits, Impedance, Devanathan-Stachurski, Absorption, Preequilibrium
Citation
Harrington, D.A. (2020). Simplifying mechanistic impedances. Electrochimica Acta, 338, 135895. https://doi.org/10.1016/j.electacta.2020.135895