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Designing Cascades of Electron Transfer Processes in Multicomponent Graphene Conjugates.

ABSTRACT: A novel family of nanocarbon-based materials was designed, synthesized, and probed within the context of charge-transfer cascades. We integrated electron-donating ferrocenes with light-harvesting/electron-donating (metallo)porphyrins and electron-accepting graphene nanoplates (GNP) into multicomponent conjugates. To control the rate of charge flow between the individual building blocks, we bridged them via oligo-p-phenyleneethynylenes of variable lengths by ?-linkages and the Prato-Maggini reaction. With steady-state absorption, fluorescence, Raman, and XPS measurements we realized the basic physico-chemical characterization of the photo- and redox-active components and the multicomponent conjugates. Going beyond this, we performed transient absorption measurements and corroborated by single wavelength and target analyses that the selective (metallo)porphyrin photoexcitation triggers a cascade of charge transfer events, that is, charge separation, charge shift, and charge recombination, to enable the directed charge flow. The net result is a few nanosecond-lived charge-separated state featuring a GNP-delocalized electron and a one-electron oxidized ferrocenium.

SUBMITTER: Limosani F

PROVIDER: S-EPMC7756474 | biostudies-literature | 2020 Dec

REPOSITORIES: biostudies-literature

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Designing Cascades of Electron Transfer Processes in Multicomponent Graphene Conjugates.

Limosani Francesca F Kaur Ramandeep R Cataldo Antonino A Bellucci Stefano S Micciulla Federico F Zanoni Robertino R Lembo Angelo A Wang Bingzhe B Pizzoferrato Roberto R Guldi Dirk M DM Tagliatesta Pietro P

Angewandte Chemie (International ed. in English) 20201015 52

A novel family of nanocarbon-based materials was designed, synthesized, and probed within the context of charge-transfer cascades. We integrated electron-donating ferrocenes with light-harvesting/electron-donating (metallo)porphyrins and electron-accepting graphene nanoplates (GNP) into multicomponent conjugates. To control the rate of charge flow between the individual building blocks, we bridged them via oligo-p-phenyleneethynylenes of variable lengths by β-linkages and the Prato-Maggini react ...[more]

PMID: 32886436

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Dataset Information

Designing Cascades of Electron Transfer Processes in Multicomponent Graphene Conjugates.

Publications

Designing Cascades of Electron Transfer Processes in Multicomponent Graphene Conjugates.

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