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Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles
Temperaturna zavisnost elektrohemijske redukcije kiseonika na nanočesticama platine na ugljeničnom nosaču
dc.creator | Elezović, Nevenka R. | |
dc.creator | Babić, Biljana M. | |
dc.creator | Krstajić, Nedeljko V. | |
dc.creator | Gojković, Snežana Lj. | |
dc.creator | Vračar, Ljiljana M. | |
dc.date.accessioned | 2021-03-10T10:59:52Z | |
dc.date.available | 2021-03-10T10:59:52Z | |
dc.date.issued | 2008 | |
dc.identifier.issn | 0352-5139 | |
dc.identifier.uri | http://TechnoRep.tmf.bg.ac.rs/handle/123456789/1346 | |
dc.description.abstract | The temperature dependence of oxygen reduction reaction (ORR) was studied on highly dispersed Pt nanoparticles supported on a carbon cryo-gel. The specific surface area of the support was 517 m2 g-1, the Pt particles diameter was about 2.7 nm and the loading of the catalyst was 20 wt.%. The kinetics of the ORR at the Pt/C electrode was examined in 0.50 mol dm-3 HClO4 solution in the temperature range from 274 to 318 K. At all temperatures, two distinct E-log j regions were observed; at low current densities with a slope of -2.3RT/F and at high current densities with a slope of -2.3´2RT/F. In order to confirm the mechanism of oxygen reduction previously suggested at a polycrystalline Pt and a Pt/Ebonex nanostructured electrode, the apparent enthalpies of activation at selected potentials vs. the reversible hydrogen electrode were calculated in both current density regions. Although ∆H ≠a,1 gt ∆H ≠a,h , it was a,1 a, h found that the enthalpies of activation at the zero Galvani potential difference were the same and hence it could be concluded that the rate-determining step of the ORR was the same in both current density regions. The synthesized Pt/C catalyst showed a small enhancement in the catalytic activity for ORR in comparison to the polycrystalline Pt, but no change in the mechanism of the reaction. | en |
dc.description.abstract | Kinetika reakcije redukcije kiseonika je ispitivana na nanočesticama platine dispergovanim na ugljeničnom nosaču, u 0,50 mol dm-3 HClO4, u temperaturnom intervalu od 278 do 318 K. Za sintezu Pt katalizatora (Pt/C) je primenjena modifikovana poliol metoda iz rastvora etilen glikola, dok je kao nosač korišćen ugljenični kriogel. Katalizator je okarakterisan primenom BET metode, difrakcije X-zraka (XRD) i transmisione elektronske mikroskopije (TEM). Kinetika reakcije redukcije kiseonika ispitivana je korišćenjem stacionarne polarizacione metode i metode ciklične voltametrije. Oblast malih gustina struje, na svim teperaturama, na krivoj polarizacije, karakteriše vrednost Tafelovog nagiba od -2.3RT/F, dok je u oblasti visokih gustina struje vrednost ovog nagiba -2.3x2RT/F. Određene su vrednosti prividne entalpije aktivacije na konstantnim potencijalima, za obe oblasti gustina struja, i njihova razlika iskazana za nulu Galvanijeve razlike potencijala. Potvrđeno je da je mehanizam redukcije kiseonika, kao i stupanj koji određuje ukupnu brzinu reakcije isti u obe oblasti gustina struja, a da je razlika u kinetici reakcije posledica razlike u zavisnosti adsorpcije reakcionih intermedijara od potencijala. Poređenjem katalitičke aktivnosti, izražene preko gustine struje po realnoj površini katalizatora, konstatovana je nešto veća aktivnost Pt/C katalizatora u odnosu na polikristalnu Pt. | sr |
dc.publisher | Serbian Chemical Society, Belgrade | |
dc.relation | info:eu-repo/grantAgreement/MESTD/MPN2006-2010/142038/RS// | |
dc.rights | openAccess | |
dc.rights.uri | https://creativecommons.org/licenses/by-nc-nd/4.0/ | |
dc.source | Journal of the Serbian Chemical Society | |
dc.subject | oxygen reduction reaction | en |
dc.subject | platinum catalyst | en |
dc.subject | carbon support | en |
dc.subject | temperature dependence | en |
dc.subject | enthalpy of activation | en |
dc.title | Temperature dependence of the kinetics of oxygen reduction on carbon-supported pt nanoparticles | en |
dc.title | Temperaturna zavisnost elektrohemijske redukcije kiseonika na nanočesticama platine na ugljeničnom nosaču | sr |
dc.type | article | |
dc.rights.license | BY-NC-ND | |
dc.citation.epage | 654 | |
dc.citation.issue | 6 | |
dc.citation.other | 73(6): 641-654 | |
dc.citation.rank | M23 | |
dc.citation.spage | 641 | |
dc.citation.volume | 73 | |
dc.identifier.fulltext | http://TechnoRep.tmf.bg.ac.rs/bitstream/id/10811/0352-51390806641E.pdf | |
dc.identifier.rcub | https://hdl.handle.net/21.15107/rcub_technorep_1346 | |
dc.identifier.scopus | 2-s2.0-47049105414 | |
dc.identifier.wos | 000258789700005 | |
dc.type.version | publishedVersion |