Photocatalytic Water Reduction and Study of the Formation of FeIFe0 Species in Diiron Catalyst Sytems
2012 (English)In: ChemSusChem, ISSN 1864-5631, Vol. 5, no 5, 913-919 p.Article in journal (Refereed) Published
Noble-metal-free systems with bio-inspired diiron dithiolate mimics of the [FeFe]-hydrogenase active site, namely, [(mu-pdt)Fe2(CO)5L] [pdt=propanedithiolate; L=P(CH2OH)3 (1), P(CH3)3 (2)], as water reduction catalysts with xanthene dyes as photosensitizers and triethylamine as a sacrificial electron donor were studied for visible-light-driven water reduction to hydrogen. These systems display good catalytic activities with the efficiencies in hydrogen evolution of up to 226 turnovers for 1, if Eosin Y was used as the photosensitizer in an environmentally benign solvent (EtOH/H2O) after 15 h of irradiation (?>450 nm) under optimal conditions. Under all of the conditions adopted, 1 that has a water soluble phosphine ligand, P(CH2OH)3 displayed a higher efficiency than 2, which bears a PMe3 ligand. The photoinduced electron transfer in the systems was studied using fluorescence, transient absorption, time-resolved UV/Vis, and in situ electron paramagnetic resonance (EPR) spectroscopy. A new electron-transfer mechanism is proposed for hydrogen evolution by these iron-based photocatalytic systems.
Place, publisher, year, edition, pages
2012. Vol. 5, no 5, 913-919 p.
dyes, pigments, enzymes, hydrogen, iron, photocatalysis
IdentifiersURN: urn:nbn:se:kth:diva-96450DOI: 10.1002/cssc.201100490ISI: 000303854800014ScopusID: 2-s2.0-84861157656OAI: oai:DiVA.org:kth-96450DiVA: diva2:530761
FunderSwedish Research CouncilKnut and Alice Wallenberg Foundation
QC 201206042012-06-042012-06-042012-06-04Bibliographically approved