http://www.cnr.it/ontology/cnr/individuo/prodotto/ID272266

Photocatalytic Hydrogen Evolution with a Self-Assembling Reductant-Sensitizer-Catalyst System (Articolo in rivista)

Type

Label

Photocatalytic Hydrogen Evolution with a Self-Assembling Reductant-Sensitizer-Catalyst System (Articolo in rivista) (literal)

Anno

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi

Alternative label

Natali, Mirco and Argazzi, Roberto and Chiorboli, Claudio and Iengo, Elisabetta and Scandola, Franco (2013)
Photocatalytic Hydrogen Evolution with a Self-Assembling Reductant-Sensitizer-Catalyst System
in Chemistry (Weinh., Print); WILEY-V C H VERLAG GMBH, WEINHEIM (Germania)
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

Natali, Mirco and Argazzi, Roberto and Chiorboli, Claudio and Iengo, Elisabetta and Scandola, Franco (literal)

Pagina inizio

Pagina fine

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

Rivista

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroFascicolo

Note

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

Natali, M (Reprint Author), Univ Ferrara, Dept Chem & Pharmaceut Sci, Via Fossato di Mortara 17-19, I-44121 Ferrara, Italy. Natali, Mirco; Scandola, Franco, Univ Ferrara, Dept Chem & Pharmaceut Sci, I-44121 Ferrara, Italy. Natali, Mirco; Scandola, Franco, Ctr Interuniv Convers Chim Energia Solare SOLARCH, Sez Ferrara, I-44121 Ferrara, Italy. Argazzi, Roberto; Chiorboli, Claudio, ISOF CNR, Sez Ferrara, I-44121 Ferrara, Italy. Iengo, Elisabetta, Univ Trieste, Dept Chem & Pharmaceut Sci, I-34127 Trieste, Italy. (literal)

Titolo

Photocatalytic Hydrogen Evolution with a Self-Assembling Reductant-Sensitizer-Catalyst System (literal)

Abstract

A noble-metal-free system for photochemical hydrogen production is described, based on ascorbic acid as sacrificial donor, aluminium pyridyl porphyrin as photosensitizer, and cobaloxime as catalyst. Although the aluminium porphyrin platform has docking sites for both the sacrificial donor and the catalyst, the resulting associated species are essentially inactive because of fast unimolecular reversible electron-transfer quenching. Rather, the photochemically active species is the fraction of sensitizer present, in the aqueous/organic solvent used for hydrogen evolution, as free species. As shown by nanosecond laser flash photolysis experiments, its long-lived triplet state reacts bimolecularly with the ascorbate donor, and the reduced sensitizer thus formed, subsequently reacts with the cobaloxime catalyst, thereby triggering the hydrogen evolution process. The performance is good, particularly in terms of turnover frequencies (TOF=10.8 or 3.6min-1, relative to the sensitizer or the catalyst, respectively) and the quantum yield (phi=4.6%, that is, 9.2% of maximum possible value). At high sacrificial donor concentration, the maximum turnover number (TON=352 or 117, relative to the sensitizer or the catalyst, respectively) is eventually limited by hydrogenation of both sensitizer (chlorin formation) and catalyst. (literal)

Editore