| Téléchargement | - Voir le manuscrit accepté : The electrochemical reduction of VO2+ in acidic solution at high overpotentials (PDF, 1.1 Mio)
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| DOI | Trouver le DOI : https://doi.org/10.1016/j.electacta.2005.05.001 |
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| Auteur | Rechercher : Gattrell, M.1; Rechercher : Qian, J.1; Rechercher : Stewart, C.1; Rechercher : Graham, P.1; Rechercher : MacDougall, B.1 |
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| Affiliation | - Conseil national de recherches du Canada. Institut de technologie des procédés chimiques et de l'environnement du CNRC
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| Format | Texte, Article |
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| Sujet | vanadium; High Tafel slope; adsorbed intermediates; carbon electrodes; VRBs |
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| Résumé | An investigation has been carried out to attempt to understand the unusually low apparent symmetry factor observed during the reduction of V(5) at higher overpotentials at carbon electrodes (typically <0.13, or >460mVdecade−1). This reaction is of interest because it occurs in vanadium redox-flow batteries (VRBs) during discharge. Polarisation curves were measured using a rotating disk electrode (RDE). The reaction was not solution mass transport controlled, was pH independent (ca from 0 to 1), and the observed Tafel slope was unaffected by V(5) concentration over a range from 0.031 to 280 mM. Electrode double layer capacitance measurements were also carried out in sulphuric acid with and without vanadium. These tests showed that the presence of V(5) caused a suppression of the normal carbon surface quinone pseudocapacitance, as well as the appearance of two new pseudocapacitance peaks, one around 0.175–0.2V and the other around 0.675–0.725V versus SCE. The observed results do not appear consistent with a precipitated film causing diffusion limitations or causing IR drop. A model is developed to try to explain the data, which involves electron transfer through an adsorbed layer of vanadium. |
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| Date de publication | 2005 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro du CNRC | NRCC 52277 |
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| Numéro NPARC | 16285554 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | e8942587-7f27-4b2e-9580-ff2abe6dac64 |
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| Enregistrement créé | 2010-10-27 |
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| Enregistrement modifié | 2020-04-07 |
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