Selectivities of Stepped Cu-M (M = Pt, Ni, Pd, Zn, Ag, Au) Bimetallic Surface Environment for C1 and C2 Pathways

Copper (Cu) emerges as a highly efficient and cheap catalytic agent for the electrochemical reduction of carbon dioxide (CO₂RR), promising a sustainable route toward carbon neutrality. Despite its utility, the Cu catalyst exhibits limitations in terms of product selectivity, highlighting the need for the development of a superior catalyst design. Herein, we present a density functional theory (DFT) investigation into the selectivities of Cu-M (M = Pt, Ni, Pd, Zn, Ag, Au) bimetallic catalysts (BMCs) for the carbon dioxide reduction reaction (CO₂RR). The interaction between the metals of Cu-M makes the surface electrons reconstruct so that the d-band center shifts to the Fermi level. In terms of CO₂ activation, the Cu-Ni catalyst exhibits superior performance. Additionally, the Cu-Pd catalyst favors the formation of *COH along the reaction pathway, favoring the generation of CH₄. Conversely, the Cu-Ni catalyst preferentially produces *CHO, thereby favoring the production of CH₃OH. For the Cu-Ag catalyst, the reaction intermediates along the C2 pathway are *CO-*CHO and *COH-*CHO. The Cu-Ni catalyst follows a reaction path that proceeds via *CO-*CO → *CO-*COH → *COH-CHO. On the other hand, the Cu-Pt catalyst exhibits a reaction sequence of *CO-*CO → *CO-*CHO → *OCH-*OCH. This study provides guiding significance for the design of Cu-based bimetallic catalysts aimed at improving the selectivities and efficiency of the CO₂RR process.