Potential-sweep chronoamperometry theory of kinetic currents in the case of a first order chemical reaction preceding the electron-transfer process

Savéant, Jean‐Michel; Vianello, E.

doi:10.1016/0013-4686(62)87046-7

Cited by 204 publications

(103 citation statements)

References 11 publications

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“…For large excesses of ligand, the reaction may be considered pseudo-first-order, since K is nearly constant. This is identiial to the case of a first order chemical reaction preceding the electrochemical reaction, first examined by Saveant and Vianello [12]. By recasting their treatment in terms of convolution integrals, we obtain, defining M n + as ox, and MO as red: (12) nFA E. ,1+K .. l+K ~I E-y 1 and…”

Section: Theory Linear Scan Voltammetry (Lsv)mentioning

confidence: 99%

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Convolution voltammetry of metal complexes

Toman

Corn

Brown

1981

Analytica Chimica Acta

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Section: Theory Linear Scan Voltammetry (Lsv)mentioning

confidence: 99%

“…Then equation [12] reduces to: (15) which, upon substitution into the Nernst equation, gives an unshifted wave of height proportional to the concentration of the uncomplexed metal, because of the speed of the electrochemical measurement relative to the kinetics of ligand exchange.…”

Section: Theory Linear Scan Voltammetry (Lsv)mentioning

confidence: 99%

Convolution voltammetry of metal complexes

Toman

Corn

Brown

1981

Analytica Chimica Acta

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“…To the best of our knowledge, the only possibility that may account for such behavior consists in considering that the first oxidation step proceeded through the surface equivalent of a classical CE solution mechanism 62 as sketched in Scheme 1. Within this mechanism, only a single population of dopamine molecules located on electroactive sites (noted DA el ads ) is responsible for the whole electrochemical response at all scan rates.…”

Section: Discussionmentioning

confidence: 99%

“…Would the ratio k b /k f in Scheme 1 had a significant value one should observe a significant shift in the E F)ln(1 + k b /k f ), 62 and possibly result in the development of a second oxidation wave. 21 Figures 3 and 4 do not provide any evidence for such behavior so it is inferred that…”

Section: Discussionmentioning

confidence: 99%

Surface Heterogeneities Matter in Fast Scan Cyclic Voltammetry Investigations of Catecholamines in Brain with Carbon Microelectrodes of High-Aspect Ratio: Dopamine Oxidation at Conical Carbon Microelectrodes

Oleinick

Álvarez‐Martos

Svir

et al. 2018

J. Electrochem. Soc.

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Fast Scan Cyclic Voltammetry (FSCV) at high aspect ratio carbon microelectrodes shows adequate high temporal and spatial resolution for in vivo analysis of catecholamines. Though the presence of their surface heterogeneities has been recognized since their earliest introduction for in vivo measurements in the brain, the kinetic consequences on the measurements have not been investigated and FSCV measurements are treated based on pre-and post-calibrations. We establish here that surface heterogeneities play a consequent dynamic role on the oxidation of dopamine taken as an example of catecholamines. Hence, the FSCV current peak intensities do not scale with the scan rate v or its square root. This is rationalized with a simple model involving a co-existence of at least two types of surface nanodomains with different electrochemical reactivities and different time responses. At low scan rates (<100 V s −1 ) dopamine molecules that initially adsorbed onto non-electroactive nanodomains have enough time to migrate toward highly electroactive ones so all molecules initially adsorbed on the whole electrode surface may be oxidized during one FSCV cycle. Current peak intensities then increase proportionally to the scan rate. However, above 100 V s −1 , dopamine migration between sites starts to be kinetically limited so that FSCV current peak intensities do not increase any more proportionally to the scan rate. Ultimately, i.e., above 1000 V s −1 , the dopamine exchange between sites is almost totally blocked so only dopamine molecules initially adsorbed on the electroactive surface nanodomains may be oxidized; the current peak intensities then increase again proportionally with the scan rate though with a smaller slope than that observed at small scan rates. Since carbon fibers with large aspect ratios are frequently used in brain investigations, this effect should be a concern when extracting quantitative results even when each carbon fiber response is properly pre-or post-calibrated using the exact CV waveform and scan rate used during the in vivo measurements. Release and modulation of neurotransmitters fluxes and concentrations are essential in complex organisms since they regulate many key functions by transferring information between cells such as neurons in the brain, neurons and muscle cells as well as through stimulating specific actions in endocrine-related systems. Albeit their unique and ubiquitous functions are well recognized today, the very existence and identification of neurotransmitters has long been a matter of debate up to the end of the second third of the past century, 1-3 and still needs to be better understood. This explains why characterizing fluxes and nature of neurotransmitters release is still stimulating a quest for analytical methods sufficiently accurate, specific and sensitive to investigate dynamic effluxes and flows of neurotransmitters in vivo (e.g., within a living brain) 4-6 or ex vivo (e.g., at the single endocrine cell level, 7-9 or intrasynaptically 10-12 ) with an adequate tempo...

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“…The catalytic rate constant (k) can then be extracted from Eq. 3 which holds true for a reversible electron-transfer process followed by a fast catalytic reaction [38].…”

Section: Electrochemical Studiesmentioning

confidence: 98%

Using the Alkynyl-Substituted Rhenium(I) Complex (4,4′-Bisphenyl-Ethynyl-2,2′-Bipyridyl)Re(CO)3Cl as Catalyst for CO2 Reduction—Synthesis, Characterization, and Application

et al. 2014

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The synthesis, structure, photophysics, and spectroscopic characterization of an organometallic rhenium multichromophore compound carrying a central 2,2′-bipyridyl acceptor moiety with additional phenylethynyl substituents conjugated at the 4,4′-positions of the acceptor ligands and its effect on the electron density of the central rhenium atom as metal center for CO 2 reduction is reported. The results were compared to fac-(2,2′-bipyridyl)Re(CO) 3 Cl and fac-(5,5′-bisphenylethynyl-2,2′-bipyridyl)Re(CO) 3 Cl. Cyclovoltammetric studies and rotating disk electrochemistry were performed for electrochemical characterization. Ultraviolet and visible (UV-vis) absorption, Fourier transform infrared (FTIR), and luminescence measurements were carried out for a spectroscopic characterization and compared to theoretical calculations at the density functional theory (DFT) level. In addition, the rhenium complex fac-(4,4′-bisphenyl-ethynyl-2,2′-bipyridyl)-Re(CO) 3 Cl was used as a novel catalyst for the electrochemical reduction of CO 2 in homogeneous solution. Results showed an 11-fold increase in the current density under CO 2 saturation and a catalytic second-order rate constant for CO formation of about 560 M −1 s −1 on a Pt working electrode. For further characterization of the CO 2 reduction capabilities, bulk controlled potential electrolysis experiments were performed using a CO 2 -saturated acetonitrile electrolyte solution. The headspace product gas analysis yields CO as main reduction product with faradaic efficiencies of about 12 % over 5-h electrolysis time.

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Potential-sweep chronoamperometry theory of kinetic currents in the case of a first order chemical reaction preceding the electron-transfer process

Cited by 204 publications

References 11 publications

Convolution voltammetry of metal complexes

Convolution voltammetry of metal complexes

Surface Heterogeneities Matter in Fast Scan Cyclic Voltammetry Investigations of Catecholamines in Brain with Carbon Microelectrodes of High-Aspect Ratio: Dopamine Oxidation at Conical Carbon Microelectrodes

Using the Alkynyl-Substituted Rhenium(I) Complex (4,4′-Bisphenyl-Ethynyl-2,2′-Bipyridyl)Re(CO)3Cl as Catalyst for CO2 Reduction—Synthesis, Characterization, and Application

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