270740 Selective Electrocatalytic Activity of Ligand-Stabilized Copper Oxide Nanoparticles for CO2 Reduction and Methanol Oxidation
The chemical conversion and utilization of CO2 are extremely important catalytic challenges. The electrochemical conversion of CO2 over bulk copper has been widely investigated, but questions about the reaction mechanism and the influence of the catalyst surface still remain. For example, how will the presence and type of oxidized surface species influence catalytic activity? We have found that ligand-stabilized Cu2O and CuO nanoparticles can function as catalysts for the electrochemical conversion of CO2 into CO. We show that the ligand-stabilized Cu-oxide nanoparticles promote CO2 conversion more efficiently than bulk copper, bulk copper oxide, and weakly or non-ligand stabilized nanoparticles. Additionally the ligand-stabilized Cu-oxide nanoparticles were also active towards methanol oxidation, with approximately 88-100% selectivity for the conversion of methanol into formaldehyde. On the other hand, bulk Cu-oxide catalysts exclusively produced CO2. Electron microscopy, electrochemistry, a variety of spectroscopic techniques and chromatography have been used to investigate the catalyst structure, nature of the active sites, and product distributions. Our data suggests that unique reactive sites on the ligand-protected Cu-oxide nanoparticle surface promote product selectivity.