Phosphine Coordination to a Cobalt Diimine-Dioxime Catalyst Increases Stability during Light-Driven H-2 Production
2012 (English)In: Inorganic Chemistry, ISSN 0020-1669, E-ISSN 1520-510X, Vol. 51, no 4, 2115-2120 p.Article in journal (Refereed) Published
The combination of cobalt diimine-dioxime complexes with a cyclometalated iridium photosensitizer gives efficient systems for hydrogen generation under visible-light irradiation using triethylamine as a sacrificial electron donor. Interestingly, the addition of triphenylphosphine (PPh3) to the medium results in a significant improvement of the stability of the system, with up to similar to 700 turnovers achieved within 10 h. UV-visible spectroscopic monitoring of the reaction allows identification of a PPh3-coordinated Co-I intermediate as the active species. Mechanistic issues regarding (i) the photogeneration of the Co-I species, (ii) the nature of the active species, and (iii) the influence of PPh3 on the H-2-evolution mechanism are discussed.
Place, publisher, year, edition, pages
2012. Vol. 51, no 4, 2115-2120 p.
IdentifiersURN: urn:nbn:se:kth:diva-93655DOI: 10.1021/ic2019132ISI: 000300466300020ScopusID: 2-s2.0-84863266154OAI: oai:DiVA.org:kth-93655DiVA: diva2:517553
QC 201204242012-04-242012-04-232012-04-24Bibliographically approved