title: Activating a Low Overpotential CO2 Reduction Mechanism by a Strategic Ligand Modification on a Ruthenium Polypyridyl Catalyst.
abstract: The introduction of a simple methyl substituent on the bipyridine ligand of [Ru(tBu3 tpy)(bpy)(NCCH3 )](2+) (tBu3 tpy=4,4',4''-tri-tert-butyl-2,2':6',2''-terpyridine; bpy=2,2'-bipyridine) gives rise to a highly active electrocatalyst for the reduction of CO2 to CO. The methyl group enables CO2 binding already at the one-electron reduced state of the complex to enter a previously not accessible catalytic cycle that operates at the potential of the first reduction. The complex turns over with a Faradaic efficiency close to unity and at an overpotential that is amongst the lowest ever reported for homogenous CO2 reduction catalysts.
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
authors.forename: Ben A
authors.initials: BA
authors.lastname: Johnson
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
authors.forename: Somnath
authors.initials: S
authors.lastname: Maji
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
authors.forename: Hemlata
authors.initials: H
authors.lastname: Agarwala
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
authors.forename: Travis A
authors.initials: TA
authors.lastname: White
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden.
authors.forename: Edgar
authors.initials: E
authors.lastname: Mijangos
authors.affiliation: Department of Chemistry, Ångström Laboratory, Uppsala University, Box 523, 75120, Uppsala, Sweden. sascha.ott@kemi.uu.se.
authors.forename: Sascha
authors.initials: S
authors.lastname: Ott
keywords: carbon dioxide reduction; electrocatalysis; overpotential; reaction mechanisms; ruthenium