title: Ionic liquid-mediated selective conversion of CO₂ to CO at low overpotentials.
abstract: Electroreduction of carbon dioxide (CO(2))--a key component of artificial photosynthesis--has largely been stymied by the impractically high overpotentials necessary to drive the process. We report an electrocatalytic system that reduces CO(2) to carbon monoxide (CO) at overpotentials below 0.2 volt. The system relies on an ionic liquid electrolyte to lower the energy of the (CO(2))(-) intermediate, most likely by complexation, and thereby lower the initial reduction barrier. The silver cathode then catalyzes formation of the final products. Formation of gaseous CO is first observed at an applied voltage of 1.5 volts, just slightly above the minimum (i.e., equilibrium) voltage of 1.33 volts. The system continued producing CO for at least 7 hours at Faradaic efficiencies greater than 96%.
authors.affiliation: Dioxide Materials, 60 Hazelwood Drive, Champaign, IL 61820, USA.
authors.forename: Brian A
authors.initials: BA
authors.lastname: Rosen
authors.forename: Amin
authors.initials: A
authors.lastname: Salehi-Khojin
authors.forename: Michael R
authors.initials: MR
authors.lastname: Thorson
authors.forename: Wei
authors.initials: W
authors.lastname: Zhu
authors.forename: Devin T
authors.initials: DT
authors.lastname: Whipple
authors.forename: Paul J A
authors.initials: PJ
authors.lastname: Kenis
authors.forename: Richard I
authors.initials: RI
authors.lastname: Masel
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002248:Carbon Monoxide / Q000737:chemistry; D002384:Catalysis; D004563:Electrochemistry; D007093:Imidazoles / Q000737:chemistry; D007094:Imides / Q000737:chemistry; D010788:Photosynthesis; D013449:Sulfonamides
chemical_list: C493485:1-butyl-3-methylimidazolium bis((trifluoromethyl)sulfonyl)amide; D007093:Imidazoles; D007094:Imides; D013449:Sulfonamides; D002245:Carbon Dioxide; D002248:Carbon Monoxide