dc.contributor.author
Chandra, Anirban
dc.contributor.author
Mebs, Stefan
dc.contributor.author
Kundu, Subrata
dc.contributor.author
Kuhlmann, Uwe
dc.contributor.author
Hildebrandt, Peter
dc.contributor.author
Dau, Holger
dc.contributor.author
Ray, Kallol
dc.date.accessioned
2021-03-16T10:02:15Z
dc.date.available
2021-03-16T10:02:15Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/29903
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-29645
dc.description.abstract
The synthesis, spectroscopic characterization (infrared, electron paramagnetic resonance and X-ray absorption spectroscopies) and density functional theoretical calculations of a tetranuclear cobalt complex Co4L1 involving a nonheme ligand system, L1, supported on a stannoxane core are reported. Co4L1, similar to the previously reported hexanuclear cobalt complex Co6L2, shows a unique ability to catalyze dioxygen (O2) reduction, where product selectivity can be changed from a preferential 4e−/4H+ dioxygen-reduction (to water) to a 2e−/2H+ process (to hydrogen peroxide) only by increasing the temperature from −50 to 30 °C. Detailed mechanistic insights were obtained on the basis of kinetic studies on the overall catalytic reaction as well as by low-temperature spectroscopic (UV-Vis, resonance Raman and X-ray absorption spectroscopies) trapping of the end-on μ-1,2-peroxodicobalt(III) intermediate 1. The Co4L1- and Co6L2-mediated O2-reduction reactions exhibit different reaction kinetics, and yield different ratios of the 2e−/2H+ and 4e−/4H+ products at −50 °C, which can be attributed to the different stabilities of the μ-1,2-peroxodicobalt(III) intermediates formed upon dioxygen activation in the two cases. The deep mechanistic insights into the transition-metal mediated dioxygen reduction process that are obtained from the present study should serve as useful and broadly applicable principles for future design of more efficient catalysts in fuel cells.
en
dc.format.extent
9 Seiten
dc.rights.uri
https://creativecommons.org/licenses/by/4.0/
dc.subject
Catalytic dioxygen reduction
en
dc.subject
low-temperature spectroscopic (UV-Vis, resonance Raman andX-ray absorption spectroscopies
en
dc.subject
catalysts in fuel cells
en
dc.subject.ddc
500 Naturwissenschaften und Mathematik::530 Physik::530 Physik
dc.title
Catalytic dioxygen reduction mediated by a tetranuclear cobalt complex supported on a stannoxane core
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation.doi
10.1039/D0DT00475H
dcterms.bibliographicCitation.journaltitle
Dalton Transactions
dcterms.bibliographicCitation.number
18
dcterms.bibliographicCitation.originalpublishername
RSC
dcterms.bibliographicCitation.originalpublisherplace
Cambridge, London
dcterms.bibliographicCitation.pagestart
6065
dcterms.bibliographicCitation.pageend
6073
dcterms.bibliographicCitation.volume
49
dcterms.bibliographicCitation.url
http://dx.doi.org/10.1039/D0DT00475H
refubium.affiliation
Physik
refubium.affiliation.other
Institut für Experimentalphysik
refubium.resourceType.isindependentpub
no
dcterms.accessRights.openaire
open access
dcterms.isPartOf.eissn
1477-9226