title: Structure-Sensitive CO2Electroreduction to Hydrocarbons on Ultrathin 5-fold Twinned Copper Nanowires.
abstract: Copper is uniquely active for the electrocatalytic reduction of carbon dioxide (CO2) to products beyond carbon monoxide, such as methane (CH4) and ethylene (C2H4). Therefore, understanding selectivity trends for CO2electrocatalysis on copper surfaces is critical for developing more efficient catalysts for CO2conversion to higher order products. Herein, we investigate the electrocatalytic activity of ultrathin (diameter ∼20 nm) 5-fold twinned copper nanowires (Cu NWs) for CO2reduction. These Cu NW catalysts were found to exhibit high CH4selectivity over other carbon products, reaching 55% Faradaic efficiency (FE) at -1.25 V versus reversible hydrogen electrode while other products were produced with less than 5% FE. This selectivity was found to be sensitive to morphological changes in the nanowire catalyst observed over the course of electrolysis. Wrapping the wires with graphene oxide was found to be a successful strategy for preserving both the morphology and reaction selectivity of the Cu NWs. These results suggest that product selectivity on Cu NWs is highly dependent on morphological features and that hydrocarbon selectivity can be manipulated by structural evolution or the prevention thereof.
authors.forename: Yifan
authors.identifier: 0000-0003-2146-2266
authors.initials: Y
authors.lastname: Li
authors.forename: Fan
authors.identifier: 0000-0003-3394-8095
authors.initials: F
authors.lastname: Cui
authors.forename: Michael B
authors.initials: MB
authors.lastname: Ross
authors.affiliation: Kavli Energy Nanosciences Institute , Berkeley, California 94720, United States.
authors.forename: Dohyung
authors.initials: D
authors.lastname: Kim
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Sun
authors.affiliation: Kavli Energy Nanosciences Institute , Berkeley, California 94720, United States.
authors.forename: Peidong
authors.identifier: 0000-0003-4799-1684
authors.initials: P
authors.lastname: Yang
mesh_terms: D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D003300:Copper / Q000737:chemistry*; D055664:Electrochemical Techniques / Q000379:methods*; D004566:Electrodes; D006838:Hydrocarbons / Q000737:chemistry*; D053770:Nanowires / Q000737:chemistry*; D010084:Oxidation-Reduction; D010316:Particle Size; D013499:Surface Properties
chemical_list: D006838:Hydrocarbons; D002245:Carbon Dioxide; D003300:Copper
keywords: 5-fold twinned nanowires; carbon dioxide reduction; electrocatalysis; graphene oxide; morphological evolution; selectivity