Double layer capacitances analysed with impedance spectroscopy and cyclic voltammetry: validity and limits of the constant phase element parameterization

At small amplitudes, the equilibrium positions of the ions are changed. High amplitudes lead to a drastic distortion of the ion arrangement in the double layer, increasing the capacitance and asymmetric ion movements.

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The influence of water content in a proton-conducting ionic liquid on the double layer properties of the Pt/PIL interface

Physical Chemistry Chemical Physics ◽

10.1039/c7cp04003b ◽

2017 ◽

Vol 19 (36) ◽

pp. 24706-24723 ◽

Cited By ~ 11

Author(s):

K. Wippermann ◽

J. Giffin ◽

S. Kuhri ◽

W. Lehnert ◽

C. Korte

Keyword(s):

Cyclic Voltammetry ◽

Ionic Liquid ◽

Impedance Spectroscopy ◽

Water Content ◽

Double Layer ◽

Proton Conducting ◽

Influence Of Water

The influence of the water content of 2-sulfoethylmethylammonium trifluoromethanesulfonate [2-Sema][TfO] on the double layer properties of the interface of platinum and the proton conducting ionic liquid (PIL) is investigated by means of impedance spectroscopy and cyclic voltammetry.

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Impedance Spectroscopy and Cyclic Voltammetry to Determine Double Layer Capacitances and Electrochemically Active Surface Areas

10.1149/osf.io/gyexd ◽

2018 ◽

Author(s):

Maximilian Schalenbach

Keyword(s):

Cyclic Voltammetry ◽

Impedance Spectroscopy ◽

Frequency Domain ◽

Surface Area ◽

Double Layer ◽

Active Surface ◽

Scattering Data ◽

Gold Electrodes ◽

Electrochemically Active ◽

Electrochemically Active Surface

The electrochemically active surface area (ECSA) of an electrode can be estimated by means of double layer capacitance (DLC) measurements using impedance spectroscopy and cyclic voltammetry. In this study, the responses of smooth and porous gold electrodes (chosen as model systems) to both methods are measured and described by physical models. I point out that diffusion limited adsorption processes significantly contribute to the measured responses and thus complicate the estimation of DLCs. Impedance is derived to be in most cases more suitable for measuring DLCs as higher frequencies are available and as contributions of serial resistances and capacitances can be separately evaluated in the frequency domain. The relaxation properties in the frequency domain are shown to display a useful tool to survey the accuracy of the DLC estimation. The DLCs of polished gold electrodes are shown to be proportional to their geometric surface area. From these measurements a specific DLC of 6±2 μF/cm² of gold in perchloric acid is determined, which agrees with the lowest reported values of strongly scattering data in the literature. A handy flow chart for experimentalists to determine electrode capacitances from impedance spectra is proposed.

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Constant Phase Element Analysis of Ordered Carbon Electrodes Via Electrochemical Impedance Spectroscopy and Cyclic Voltammetry

ECS Meeting Abstracts ◽

10.1149/ma2021-01135mtgabs ◽

2021 ◽

Vol MA2021-01 (1) ◽

pp. 35-35

Author(s):

Gibson Paul Scisco ◽

Mark E. Orazem ◽

Kevin S. Jones ◽

Kirk J. Ziegler

Keyword(s):

Cyclic Voltammetry ◽

Electrochemical Impedance Spectroscopy ◽

Impedance Spectroscopy ◽

Constant Phase Element ◽

Electrochemical Impedance ◽

Carbon Electrodes ◽

Element Analysis

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Atypical electric behavior of the double layer. Experimental case studies: Rh(111) in aqueous HCl solutions, and Au(111) in an ionic liquid, BMIPF6

Pure and Applied Chemistry ◽

10.1351/pac-con-10-06-10 ◽

2010 ◽

Vol 83 (2) ◽

pp. 259-268 ◽

Cited By ~ 2

Author(s):

Tamás Pajkossy

Keyword(s):

Cyclic Voltammetry ◽

Ionic Liquid ◽

Double Layer ◽

Constant Phase Element ◽

Electrochemical Impedance ◽

Layer Formation ◽

Charge Potential ◽

Electric Behavior ◽

Interfacial Impedance ◽

Zero Charge Potential

Cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and zero-charge-potential measurements have been performed for the title systems. The results of the Rh(111)/aqueous HCl solutions demonstrate that in solutions of binary electrolytes with adsorbing anions the interfacial impedance is a single, indivisible element, even if its frequency dependence implies a four-element circuit. The measurements on Au(111) in 1-butyl-3-methylimidazolium hexafluorophosphate (BMIPF6) reveal that double-layer formation and rearrangement in ionic liquids are very slow processes manifesting themselves as a parallel combination of a capacitance and a constant phase element (CPE).

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