Tailoring the Selectivity of Bimetallic Copper-Palladium Nanoalloys for Electrocatalytic Reduction of CO2 to CO

Controlling the morphology and composition of bimetallic nanoalloys is an effective way to tailor their catalytic activity/selectivity for a given chemical reaction. Herein, we demonstrate the tailoring of bimetallic copper-palladium (Cu-Pd) nanoalloys with different morphologies and compositions for obtaining highly efficient electrocatalysts for the reduction of CO2 to CO. We further evaluate the catalytic performance of these Cu-Pd nanomaterials for the electrochemical conversion of CO2 to CO. In particular, the spherical Cu-Pd nanoalloys with Cu/Pd molar ratio of 1/0.3 have the highest Faradaic efficiency for CO conversion (93%), while the dendritic Cu-Pd nanoalloys have the highest Faradaic efficiency for H-2 production (65.2%) via hydrogen evolution reaction at a polarized potential of -0.87 V. The balancing of the rate-determining steps during CO2 conversion is a key factor for the observed activity/selectivity of Cu-Pd nanoalloys with different morphologies/compositions. The findings revealed in this study may shed some light on the design of cost-effective and efficient electrocatalysts for CO2 conversion to CO or to other useful hydrocarbons.