dc.contributor.author
Tichter, Tim
dc.contributor.author
Schneider, Jonathan
dc.contributor.author
Roth, Christina
dc.date.accessioned
2020-11-16T09:42:12Z
dc.date.available
2020-11-16T09:42:12Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/28869
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-28618
dc.description.abstract
The electrochemical oxidation of VO2+ at planar glassy carbon electrodes is investigated via stationary and rotating linear sweep voltammetry as well as via chronoamperometry. It is demonstrated that introducing finite kinetic rate constants into the Butler-Volmer equation captures the experimentally observed concentration dependence of the ordinate intercept in Koutecky-Levich plots that cannot be explained by using the classical model. This new concept leads to a three-term Koutecky-Levich equation considering mass transport limitations, Butler-Volmer kinetics, as well as finite heterogeneous kinetics simultaneously. Based on these findings it is pointed out that stationary linear sweep voltammetry followed by an irreversible Randles-Sevcik analysis is not sufficient for deducing the electrode kinetics of the VO2+-oxidation. In contrast, it is verified experimentally and theoretically that a Tafel analysis will still provide reasonable values of k(0) = 1.35 . 10(-5) cm/s and alpha = 0.38, respectively. Finally, it is shown that introducing the concept of finite heterogeneous kinetics into the theory of stationary linear sweep voltammetry also explains the failure of the irreversible Randles-Sevcik relation leading to an extension of the classical model and providing insight into the electrochemical oxidation reaction of VO2+.
en
dc.format.extent
10 Seiten
dc.rights.uri
https://creativecommons.org/licenses/by/4.0/
dc.subject
vanadium redox-flow batteries
en
dc.subject
rotating disc electrode
en
dc.subject
linear sweep voltammetry
en
dc.subject
Koutecky-Levich analysis
en
dc.subject
Tafel analysis
en
dc.subject.ddc
500 Naturwissenschaften und Mathematik::540 Chemie::541 Physikalische Chemie
dc.title
Finite Heterogeneous Rate Constants for the Electrochemical Oxidation of VO2+ at Glassy Carbon Electrodes
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation.articlenumber
155
dcterms.bibliographicCitation.doi
10.3389/fenrg.2020.00155
dcterms.bibliographicCitation.journaltitle
Frontiers in Energy Research
dcterms.bibliographicCitation.volume
8
dcterms.bibliographicCitation.url
https://doi.org/10.3389/fenrg.2020.00155
refubium.affiliation
Biologie, Chemie, Pharmazie
refubium.affiliation.other
Institut für Chemie und Biochemie / Physikalische und Theoretische Chemie
refubium.resourceType.isindependentpub
no
dcterms.accessRights.openaire
open access
dcterms.isPartOf.eissn
2296-598X
refubium.resourceType.provider
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