ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES

Theory is presented for the shape of current-voltage curves measured at a rotating-disc electrode for the cases where the substrate reacts either via a DISP2 or an EC2 process, and in which the kinetic step is sufficiently fast to allow the use of the reaction layer concept in the mathematical analy...

Deskribapen osoa

Xehetasun bibliografikoak
Egile Nagusiak: Compton, R, Mason, D, Unwin, P
Formatua: Journal article
Hizkuntza:English
Argitaratua: 1988
_version_ 1826257515781816320
author Compton, R
Mason, D
Unwin, P
author_facet Compton, R
Mason, D
Unwin, P
author_sort Compton, R
collection OXFORD
description Theory is presented for the shape of current-voltage curves measured at a rotating-disc electrode for the cases where the substrate reacts either via a DISP2 or an EC2 process, and in which the kinetic step is sufficiently fast to allow the use of the reaction layer concept in the mathematical analysis of the problem. It is predicted that if the measured voltammetric waves are analysed using an ordinary Tafel plot (corrected in the usual way for mass transport), then significant curvature will result, the extent of which depends on the rate constant of the chemical step following the first electron transfer. In principle this curvature of the Tafel plot permits the deduction of the second-order rate constant describing the following reaction. Additionally the half-wave potential of the voltammetric wave is found to vary by (ca.) 20 mV per decade of change in rotation speed (at 25 °C). This again allows the deduction of kinetic parameters, although in this case the appropriate formal potential for the first electron transfer must be known from some other measurement. In the case of the DISP2 mechanism the kinetics can also be deduced by studying the effective number of electrons transferred as a function of electrode rotation speed. An appropriate working curve is presented for the conditions where the reaction layer treatment may be taken to be valid.
first_indexed 2024-03-06T18:19:27Z
format Journal article
id oxford-uuid:05c75743-22e0-4381-aabb-e505485d9ffb
institution University of Oxford
language English
last_indexed 2024-03-06T18:19:27Z
publishDate 1988
record_format dspace
spelling oxford-uuid:05c75743-22e0-4381-aabb-e505485d9ffb2022-03-26T08:58:59ZROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSESJournal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:05c75743-22e0-4381-aabb-e505485d9ffbEnglishSymplectic Elements at Oxford1988Compton, RMason, DUnwin, PTheory is presented for the shape of current-voltage curves measured at a rotating-disc electrode for the cases where the substrate reacts either via a DISP2 or an EC2 process, and in which the kinetic step is sufficiently fast to allow the use of the reaction layer concept in the mathematical analysis of the problem. It is predicted that if the measured voltammetric waves are analysed using an ordinary Tafel plot (corrected in the usual way for mass transport), then significant curvature will result, the extent of which depends on the rate constant of the chemical step following the first electron transfer. In principle this curvature of the Tafel plot permits the deduction of the second-order rate constant describing the following reaction. Additionally the half-wave potential of the voltammetric wave is found to vary by (ca.) 20 mV per decade of change in rotation speed (at 25 °C). This again allows the deduction of kinetic parameters, although in this case the appropriate formal potential for the first electron transfer must be known from some other measurement. In the case of the DISP2 mechanism the kinetics can also be deduced by studying the effective number of electrons transferred as a function of electrode rotation speed. An appropriate working curve is presented for the conditions where the reaction layer treatment may be taken to be valid.
spellingShingle Compton, R
Mason, D
Unwin, P
ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title_full ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title_fullStr ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title_full_unstemmed ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title_short ROTATING-DISK ELECTRODE VOLTAMMETRY - WAVESHAPE ANALYSIS FOR DISP2 AND EC2 PROCESSES
title_sort rotating disk electrode voltammetry waveshape analysis for disp2 and ec2 processes
work_keys_str_mv AT comptonr rotatingdiskelectrodevoltammetrywaveshapeanalysisfordisp2andec2processes
AT masond rotatingdiskelectrodevoltammetrywaveshapeanalysisfordisp2andec2processes
AT unwinp rotatingdiskelectrodevoltammetrywaveshapeanalysisfordisp2andec2processes