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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'.

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Related in: MedlinePlus

Evolution of the (average) linear diffusion layer thickness in A) single-step chronoamperometry at different microelectrode shapes and B) linear sweep voltammetry at spherical electrodes of different radii at 100 mV s−1.
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fig13: Evolution of the (average) linear diffusion layer thickness in A) single-step chronoamperometry at different microelectrode shapes and B) linear sweep voltammetry at spherical electrodes of different radii at 100 mV s−1.

Mentions: Equations 27–29 and 31–32 enable the study of the behaviour of the linear diffusion layer for very different electrodes geometries and voltammetric techniques. Figure 3 shows the evolution of the (average) linear diffusion layer thickness in chronoamperommetric (Figure 3 a) and linear sweep voltammetry (Figure 3 b) experiments at microelectrodes of different shape (Figure 3 a ) and different radii (Figure 3 b). In both experiments, the thickness of the linear diffusion layer increases as the experiment proceeds and so the duration of the perturbation. Regarding the electrode shape (Figure 13 a), for a given r0, the δ values coincide for any geometry at very short times when diffusion is predominantly planar, with differences between them becoming more apparent with time. Thus, δ decreases in the order: cylindrical>band>spherical>disc, which means that the mass-transport efficiency (current density) follows the inverse order. With respect to the influence of the electrode size (Figure 13 b), the thickness of the linear diffusion layer in absolute terms decreases as the electrode shrinks, though the thickness relative to the electrode radius (i.e. δ/r0) increases, and it tends to 1 at microelectrodes.


Recent Advances in Voltammetry.

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

Evolution of the (average) linear diffusion layer thickness in A) single-step chronoamperometry at different microelectrode shapes and B) linear sweep voltammetry at spherical electrodes of different radii at 100 mV s−1.
© Copyright Policy - open-access
Related In: Results  -  Collection

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

fig13: Evolution of the (average) linear diffusion layer thickness in A) single-step chronoamperometry at different microelectrode shapes and B) linear sweep voltammetry at spherical electrodes of different radii at 100 mV s−1.
Mentions: Equations 27–29 and 31–32 enable the study of the behaviour of the linear diffusion layer for very different electrodes geometries and voltammetric techniques. Figure 3 shows the evolution of the (average) linear diffusion layer thickness in chronoamperommetric (Figure 3 a) and linear sweep voltammetry (Figure 3 b) experiments at microelectrodes of different shape (Figure 3 a ) and different radii (Figure 3 b). In both experiments, the thickness of the linear diffusion layer increases as the experiment proceeds and so the duration of the perturbation. Regarding the electrode shape (Figure 13 a), for a given r0, the δ values coincide for any geometry at very short times when diffusion is predominantly planar, with differences between them becoming more apparent with time. Thus, δ decreases in the order: cylindrical>band>spherical>disc, which means that the mass-transport efficiency (current density) follows the inverse order. With respect to the influence of the electrode size (Figure 13 b), the thickness of the linear diffusion layer in absolute terms decreases as the electrode shrinks, though the thickness relative to the electrode radius (i.e. δ/r0) increases, and it tends to 1 at microelectrodes.

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