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 CO 2 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 Cu 3 Pd (CRD‐Cu 3 Pd) decreases the onset potential for methane (CH 4 ) by 200 mV and shows a sevenfold CH 4 current density at −1.2 V (vs reversible hydrogen electrode) compared to Cu foil. The flower‐like Pd 3 Cu (FL‐Pd 3 Cu) 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 CH 4 current of CRD‐Cu 3 Pd, while the alloy effect is responsible for high CO selectivity of FL‐Pd 3 Cu.