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Recent Advances in Voltammetry.

Batchelor-McAuley C, Kätelhön E, Barnes EO, Compton RG, Laborda E, Molina A - ChemistryOpen (2015)

Bottom Line: 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'.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford South Parks Road, Oxford, OX1 3QZ, UK.

ABSTRACT
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'.

No MeSH data available.


Related in: MedlinePlus

Simulation of one-electron oxidation process. α=β=0.5, DA=DB=1×10−5 cm2s−1, Eo=0, ν=0.1 V s−1, electrode area=0.0707 cm2, C✶A=0.001 m, k0 ranges from 1 cm s−1 to 1×10−10 cm s−1. Reproduced with permission from Ref. 143. Copyright 2010, Elsevier.
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fig19: Simulation of one-electron oxidation process. α=β=0.5, DA=DB=1×10−5 cm2s−1, Eo=0, ν=0.1 V s−1, electrode area=0.0707 cm2, C✶A=0.001 m, k0 ranges from 1 cm s−1 to 1×10−10 cm s−1. Reproduced with permission from Ref. 143. Copyright 2010, Elsevier.

Mentions: k0 is the standard electrochemical rate constant, α is the Butler–Volmer transfer coefficient9,143 and [X]0 is the surface concentration of species X. It is well known that as k0 decreases in size, an overpotential is required to ‘drive’ the electrode process. In terms of cyclic voltammetry this is revealed by an increase in the peak-to-peak separation in terms of the potential as shown in Figure 19 which has been calculated for a typical macroelectrode, radius 0.15 cm, and a voltage scan rate of 0.1 V s−1. The value of k0 ranges from 10−12 to 10−2 m s−1, which spans the range from electrochemically irreversible, through quasi-reversible to fully electrochemically reversible, where the term electrochemical reversibility indicates the speed of the electron transfer (k0) relative to the prevailing rate of mass transport (kMT∼D/r where D is the analyte diffusion coefficient). The Randles–Ševčík equation for the voltammetric peak current of a reversible overall n-electron reduction process is:70


Recent Advances in Voltammetry.

Batchelor-McAuley C, Kätelhön E, Barnes EO, Compton RG, Laborda E, Molina A - ChemistryOpen (2015)

Simulation of one-electron oxidation process. α=β=0.5, DA=DB=1×10−5 cm2s−1, Eo=0, ν=0.1 V s−1, electrode area=0.0707 cm2, C✶A=0.001 m, k0 ranges from 1 cm s−1 to 1×10−10 cm s−1. Reproduced with permission from Ref. 143. Copyright 2010, Elsevier.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4522172&req=5

fig19: Simulation of one-electron oxidation process. α=β=0.5, DA=DB=1×10−5 cm2s−1, Eo=0, ν=0.1 V s−1, electrode area=0.0707 cm2, C✶A=0.001 m, k0 ranges from 1 cm s−1 to 1×10−10 cm s−1. Reproduced with permission from Ref. 143. Copyright 2010, Elsevier.
Mentions: k0 is the standard electrochemical rate constant, α is the Butler–Volmer transfer coefficient9,143 and [X]0 is the surface concentration of species X. It is well known that as k0 decreases in size, an overpotential is required to ‘drive’ the electrode process. In terms of cyclic voltammetry this is revealed by an increase in the peak-to-peak separation in terms of the potential as shown in Figure 19 which has been calculated for a typical macroelectrode, radius 0.15 cm, and a voltage scan rate of 0.1 V s−1. The value of k0 ranges from 10−12 to 10−2 m s−1, which spans the range from electrochemically irreversible, through quasi-reversible to fully electrochemically reversible, where the term electrochemical reversibility indicates the speed of the electron transfer (k0) relative to the prevailing rate of mass transport (kMT∼D/r where D is the analyte diffusion coefficient). The Randles–Ševčík equation for the voltammetric peak current of a reversible overall n-electron reduction process is:70

Bottom Line: 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'.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry, Physical and Theoretical Chemistry Laboratory, University of Oxford South Parks Road, Oxford, OX1 3QZ, UK.

ABSTRACT
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'.

No MeSH data available.


Related in: MedlinePlus