title: Formation of Copper Catalysts for CO2 Reduction with High Ethylene/Methane Product Ratio Investigated with In Situ X-ray Absorption Spectroscopy.
abstract: Nanostructured copper cathodes are among the most efficient and selective catalysts to date for making multicarbon products from the electrochemical carbon dioxide reduction reaction (CO2RR). We report an in situ X-ray absorption spectroscopy investigation of the formation of a copper nanocube CO2RR catalyst with high activity that highly favors ethylene over methane production. The results show that the precursor for the copper nanocube formation is copper(I)-oxide, not copper(I)-chloride as previously assumed. A second route to an electrochemically similar material via a copper(II)-carbonate/hydroxide is also reported. This study highlights the importance of using oxidized copper precursors for constructing selective CO2 reduction catalysts and shows the precursor oxidation state does not affect the electrocatalyst selectivity toward ethylene formation.
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States.|SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University , 443 Via Ortega, Stanford, California 95305, United States.
authors.forename: André
authors.initials: A
authors.lastname: Eilert
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States.|SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University , 443 Via Ortega, Stanford, California 95305, United States.
authors.forename: F Sloan
authors.initials: FS
authors.lastname: Roberts
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States.|SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University , 443 Via Ortega, Stanford, California 95305, United States.
authors.forename: Daniel
authors.initials: D
authors.lastname: Friebel
authors.affiliation: SLAC National Accelerator Laboratory , 2575 Sand Hill Road, Menlo Park, California 94025, United States.|SUNCAT Center for Interface Science and Catalysis, Department of Chemical Engineering, Stanford University , 443 Via Ortega, Stanford, California 95305, United States.|Department of Physics, AlbaNova University Center, Stockholm University , Roslagstullsbacken 21, S-10691 Stockholm, Sweden.
authors.forename: Anders
authors.initials: A
authors.lastname: Nilsson