Access to enhanced differences in Marcus–Hush and Butler–Volmer electron transfer theories by systematic analysis of higher order AC harmonics

Stevenson, Gareth P; Baker, Ruth E.; Kennedy, Gareth; Bond, Alan M.; Gavaghan, David; Gillow, Kathryn

doi:10.1039/c2cp43193a

Cited by 15 publications

(11 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Differential pulse techniques in reverse or cyclic modes are of particular value given that, as shown in Figure , they enable simultaneous examination of the reduction and oxidation processes, which is essential to confirm the consistency of the kinetic parameters obtained from the fitting of experimental data . Also, the value of the large amplitude Fourier‐transformed AC voltammetry has been examined . The analysis of the higher order harmonic responses and the frequency‐dependence of the peak heights of the harmonics is predicted to be very powerful and sensitive in the study of the applicability of the different kinetic models and the extraction of kinetic parameters.…”

Section: Section 2: Challenging Butler–volmer Theorymentioning

confidence: 99%

Recent Advances in Voltammetry

et al. 2015

View full text Add to dashboard Cite

Recent progress in the theory and practice of voltammetry is surveyed and evaluated. The transformation over the last decade of the level of modelling and simulation of experiments has realised major advances such that electrochemical techniques can be fully developed and applied to real chemical problems of distinct complexity. This review focuses on the topic areas of: multistep electrochemical processes, voltammetry in ionic liquids, the development and interpretation of theories of electron transfer (Butler–Volmer and Marcus–Hush), advances in voltammetric pulse techniques, stochastic random walk models of diffusion, the influence of migration under conditions of low support, voltammetry at rough and porous electrodes, and nanoparticle electrochemistry. The review of the latter field encompasses both the study of nanoparticle-modified electrodes, including stripping voltammetry and the new technique of ‘nano-impacts’.

show abstract

Section: Section 2: Challenging Butler–volmer Theorymentioning

confidence: 99%

Recent Advances in Voltammetry

et al. 2015

View full text Add to dashboard Cite

show abstract

“…16,17 It has been theoretically demonstrated that Fourier-transformed alternating current voltammetry (FTACV) has a substantially enhanced ability to amplify the difference between the BV and MH models for a surface-confined process. 18 FTACV also rejects double-layer charging current and is generally advantageous compared to DC cyclic voltammetry (DCCV) for quantitative investigations of fast electrode kinetics. 19,20 In this study, it is now demonstrated that the MH model provides a significantly superior prediction of FTACV experimental data than the BV model for the oxidation of dissolved decamethylferrocene (DmFc) at an octanethiolmodified Au electrode in propylene carbonate.…”

Section: ■ Introductionmentioning

confidence: 99%

Demonstration of Superiority of the Marcus–Hush Electrode Kinetic Model in the Electrochemistry of Dissolved Decamethylferrocene at a Gold-Modified Electrode by Fourier-Transformed Alternating Current Voltammetry

Kennedy

Bond

2018

J. Phys. Chem. C

Self Cite

View full text Add to dashboard Cite

Fourier-transformed alternating current (AC) voltammetry is used to compare the applicability of the Butler−Volmer (BV) and Marcus−Hush (MH) models of electrode kinetics (k 0 ) to an outer-sphere electrode process where both oxidized and reduced species are soluble. According to numerical simulations, differences between the two models can be revealed clearly by analysis of the AC harmonics when the values of k 0 and reorganization energy are sufficiently small. Experimentally a Au electrode coated with a self-assembled octanethiol monolayer was introduced to decrease the rate of the DmFc 0/+ (DmFc = decamethylferrocene) process, a well-known outer-sphere process in a propylene carbonate solution containing 0.10 M tetrapropylammonium tetrafluoroborate. Based on a comparison of the computationally generated best fits, it was demonstrated that the MH model provides substantially better agreement with the experimental data than the BV model for the DmFc 0/+ process, unlike some other examples in the literature that favor the BV model.

show abstract

“…In recent work, we have shown that the sensitivity of Fourier transform ac voltammetry to small changes in electrode kinetics is significantly enhanced relative to the dc voltammetric case. For example, differences in wave shapes and current magnitudes arising from the use of Marcus–Hush theory as an alternative to Butler–Volmer theory for electron transfer with surface-confined molecules are significantly amplified in the ac method.…”

Section: Introductionmentioning

confidence: 99%

Theoretical Analysis of the Relative Significance of Thermodynamic and Kinetic Dispersion in the dc and ac Voltammetry of Surface-Confined Molecules

et al. 2015

Self Cite

View full text Add to dashboard Cite

Commonly, significant discrepancies are reported in theoretical and experimental comparisons of dc voltammograms derived from a monolayer or close to monolayer coverage of redox-active surface-confined molecules. For example, broader-than-predicted voltammetric wave shapes are attributed to the thermodynamic or kinetic dispersion derived from distributions in reversible potentials (E(0)) and electrode kinetics (k(0)), respectively. The recent availability of experimentally estimated distributions of E(0) and k(0) values derived from the analysis of data for small numbers of surface-confined modified azurin metalloprotein molecules now allows more realistic modeling to be undertaken, assuming the same distributions apply under conditions of high surface coverage relevant to voltammetric experiments. In this work, modeling based on conventional and stochastic kinetic theory is considered, and the computationally far more efficient conventional model is shown to be equivalent to the stochastic one when large numbers of molecules are present. Perhaps unexpectedly, when experimentally determined distributions of E(0) and k(0) are input into the model, thermodynamic dispersion is found to be unimportant and only kinetic dispersion contributes significantly to the broadening of dc voltammograms. Simulations of ac voltammetric experiments lead to the conclusion that the ac method, particularly when the analysis of kinetically very sensitive higher-order harmonics is undertaken, are far more sensitive to kinetic dispersion than the dc method. ac methods are therefore concluded to provide a potentially superior strategy for addressing the inverse problem of determining the k(0) distribution that could give rise to the apparent anomalies in surface-confined voltammetry.

show abstract

Access to enhanced differences in Marcus–Hush and Butler–Volmer electron transfer theories by systematic analysis of higher order AC harmonics

Cited by 15 publications

References 36 publications

Recent Advances in Voltammetry

Recent Advances in Voltammetry

Demonstration of Superiority of the Marcus–Hush Electrode Kinetic Model in the Electrochemistry of Dissolved Decamethylferrocene at a Gold-Modified Electrode by Fourier-Transformed Alternating Current Voltammetry

Theoretical Analysis of the Relative Significance of Thermodynamic and Kinetic Dispersion in the dc and ac Voltammetry of Surface-Confined Molecules

Contact Info

Product

Resources

About