title: Photochemical Reduction of CO2with Visible Light Using a Polyoxometalate as Photoreductant.
abstract: The photochemical reduction of CO2to CO requires two electrons and two protons that, in the past, have been derived from sacrificial amine donors that are also non-innocent in the catalytic cycle. Towards the realization of a water-splitting reaction as the source of electrons and protons for CO2reduction, we have found that a reduced acidic polyoxometalate, H5PWV2W10O40, is a photoactive electron and proton donor with visible light through excitation of the intervalence charge-transfer band. Upon linking the polyoxometalate to a dirhenium molecular catalyst, a cascade of transformations occurs where the polyoxometalate is electrochemically reduced at a relatively low negative potential of 1.3 V versus Ag/AgNO3and visible light, a 60 W tungsten lamp, or a red LED is used to transfer electrons from the polyoxometalate to the dirhenium catalyst active for the selective reduction of CO2to CO.
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel.
authors.forename: Eynat
authors.initials: E
authors.lastname: Haviv
authors.affiliation: Department of Chemical Research Support, Weizmann Institute of Science, Rehovot, 76100, Israel.
authors.forename: Linda J W
authors.initials: LJ
authors.lastname: Shimon
authors.affiliation: Department of Organic Chemistry, Weizmann Institute of Science, Rehovot, 76100, Israel.
authors.forename: Ronny
authors.identifier: 0000-0002-5530-1287
authors.initials: R
authors.lastname: Neumann
keywords: CO2 chemistry; N-ligands; photocatalysis; polyoxometalates; rhenium