Morphological and Compositional Design of Pd–Cu Bimetallic Nanocatalysts with Controllable Product Selectivity toward CO2 Electroreduction

Electrochemical conversion of carbon dioxide (electrochemical reduction of carbon dioxide) to value‐added products is a promising way to solve CO₂ emission problems. This paper describes a facile one‐pot approach to synthesize palladium–copper (Pd–Cu) bimetallic catalysts with different structures. Highly efficient performance and tunable product distributions are achieved due to a coordinative function of both enriched low‐coordinated sites and composition effects. The concave rhombic dodecahedral Cu₃Pd (CRD‐Cu₃Pd) decreases the onset potential for methane (CH₄) by 200 mV and shows a sevenfold CH₄ current density at ?1.2 V (vs reversible hydrogen electrode) compared to Cu foil. The flower‐like Pd₃Cu (FL‐Pd₃Cu) exhibits high faradaic efficiency toward CO in a wide potential range from ?0.7 to ?1.3 V, and reaches a fourfold CO current density at ?1.3 V compared to commercial Pd black. Tafel plots and density functional theory calculations suggest that both the introduction of high‐index facets and alloying contribute to the enhanced CH₄ current of CRD‐Cu₃Pd, while the alloy effect is responsible for high CO selectivity of FL‐Pd₃Cu.