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dc.contributor.authorPerova, Tatianaen
dc.contributor.authorColavita, Paulaen
dc.contributor.authorCosta de Oliveira, Maidaen
dc.date.accessioned2024-12-03T09:38:55Z
dc.date.available2024-12-03T09:38:55Z
dc.date.issued2024en
dc.date.submitted2024en
dc.identifier.citationMaida Costa de Oliveira, Christian Schr�der, Marc Brunet-Cabr�, Hugo Nolan, Antoni Forner-Cuenca, Tatiana S. Perova, Kim McKelvey, Paula E. Colavita, Effects of N-functional groups on the electron transfer kinetics of VO<sup>2+</sup>/VO<sub>2</sub><sup>+</sup> at carbon: Decoupling morphology from chemical effects using model systems, Electrochimica Acta, 475, 143640, 2024, 11en
dc.identifier.otherYen
dc.descriptionPUBLISHEDen
dc.description.abstractCarbons and nanocarbons are important electrode materials for vanadium redox flow battery applications, however, the kinetics of vanadium species are often sluggish at these surfaces, thus prompting interest in functionalization strategies to improve performance. Herein, we investigate the effect of N-functionalities on the VO2+/VO2 + redox process at carbon electrodes. We fabricate thin film carbon disk electrodes that are metal-free, possess well-defined geometry and display smooth topography, while featuring different N-site distribution, thus enabling a mechanistic investigation of the intrinsic surface activity towards VO2+/VO2 +. Voltammetry and electrochemical impedance spectroscopy show that N-functionalities improve performance, with pyridinic/ pyrrolic-N imparting the most significant improvements in charge transfer rates and reversibility, compared to graphitic-N. This was further supported by voltammetry studies on nitrogen-free electrodes modified via aryl diazonium chemistry with molecular pyridyl adlayers. Computational modeling using an electrochemical chemical mechanism indicates that introduction of surface pyridinic/pyrrolic-N can increase the heteroge neous rate constants by approximately two orders of magnitude relative to those observed at nitrogen-free carbon (k0 = 1.29 × 10− 4 vs 9.34 × 10− 7 cm/s). Simulations also suggest that these N-functionalities play a role in affecting reaction rates in the chemical step. Our results indicate that nitrogen incorporation via basic functional groups offers an interesting route to the design of advanced carbon electrodes for VRFB devices.en
dc.format.extent11en
dc.language.isoenen
dc.relation.ispartofseriesElectrochimica Actaen
dc.relation.ispartofseries475en
dc.relation.ispartofseries143640en
dc.relation.urihttps://doi.org/10.1016/j.electacta.2023.143640en
dc.rightsYen
dc.subjectElectrocatalysisen
dc.subjectFinite element simulationsen
dc.subjectHeterogeneous charge transferen
dc.subjectAryldiazoniumen
dc.subjectPervanadylen
dc.subjectVanadylen
dc.subjectVanadiumen
dc.titleEffects of N-functional groups on the electron transfer kinetics of VO<sup>2+</sup>/VO<sub>2</sub><sup>+</sup> at carbon: Decoupling morphology from chemical effects using model systemsen
dc.typeJournal Articleen
dc.type.supercollectionscholarly_publicationsen
dc.type.supercollectionrefereed_publicationsen
dc.identifier.peoplefinderurlhttp://people.tcd.ie/perovaten
dc.identifier.peoplefinderurlhttp://people.tcd.ie/costademen
dc.identifier.peoplefinderurlhttp://people.tcd.ie/colavitpen
dc.identifier.rssinternalid261796en
dc.identifier.doihttps://doi.org/10.1016/j.electacta.2023.143640en
dc.rights.ecaccessrightsopenAccess
dc.relation.citesCitesen
dc.subject.TCDThemeNanoscience & Materialsen
dc.subject.TCDTagMaterials, Physical Propertiesen
dc.identifier.orcid_id0000-0002-1017-9847en
dc.status.accessibleNen
dc.contributor.sponsorScience Foundation Ireland (SFI)en
dc.contributor.sponsorGrantNumber19/FFP/6761en
dc.identifier.urihttps://hdl.handle.net/2262/110419


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