biostudies-literatureKoike KCore Research for Evolutional Science and TechnologyOffice of ScienceJapan Society for the Promotion of Science2961-2974https://www.ebi.ac.uk/biostudies/studies/S-EPMC5897880biostudies-literatureUnknown9(11)Supramolecular photocatalysts in which Ru(ii) photosensitizer and Re(i) catalyst units are connected to each other by an ethylene linker are among the best known, most effective and durable photocatalytic systems for CO2 reduction. In this paper we report, for the first time, time-resolved infrared (TRIR) spectra of three of these binuclear complexes to uncover why the catalysts function so efficiently. Selective excitation of the Ru unit with a 532 nm laser pulse induces slow intramolecular electron transfer from the 3MLCT excited state of the Ru unit to the Re unit, with rate constants of (1.0-1.1) × 104 s-1 as a major component and (3.5-4.3) × 106 s-1 as a minor component, in acetonitrile. The produced charge-separated state has a long lifetime, with charge recombination rate constants Chemical scienceInvestigation of excited state, reductive quenching, and intramolecular electron transfer of Ru(ii)-Re(i) supramolecular photocatalysts for CO2 reduction using time-resolved IR measurements.PMC5897880Kakenhi JP17H06375DE-SC0012704DEAC02-98CH10886JPMJCR13L1Tamaki YOkubo KYamazaki YMukuta TSaigo MIshitani OFujita EGrills DCOnda KKoike KfalseInvestigation of excited state, reductive quenching, and intramolecular electron transfer of Ru(ii)-Re(i) supramolecular photocatalysts for CO2 reduction using time-resolved IR measurements.Supramolecular photocatalysts in which Ru(ii) photosensitizer and Re(i) catalyst units are connected to each other by an ethylene linker are among the best known, most effective and durable photocatalytic systems for CO2 reduction. In this paper we report, for the first time, time-resolved infrared (TRIR) spectra of three of these binuclear complexes to uncover why the catalysts function so efficiently. Selective excitation of the Ru unit with a 532 nm laser pulse induces slow intramolecular electron transfer from the 3MLCT excited state of the Ru unit to the Re unit, with rate constants of (1.0-1.1) × 104 s-1 as a major component and (3.5-4.3) × 106 s-1 as a minor component, in acetonitrile. The produced charge-separated state has a long lifetime, with charge recombination rate constants 2018-01-01T00:00:00Z2018 Mar2025-04-04T13:34:23.693Z2019-03-26T23:36:06ZS-EPMC58978802971967710.1039/c7sc05338j