Boosting efficient C-C Coupling toward Electrocatalytic Acetate Synthesis from CO2 via Close Cu+/Ag Dual Active Sites

Efficiency of C-C bond coupling in highly inert CO 2 is relatively low, which severely limits its efficient conversion to acetate. Here, we successfully developed a highly stable NF@CoMn 2 O 4 @Cu 2 O-Ag bimetallic active site catalyst by anchoring Ag on the Cu 2 O surface. In this catalyst, the Co 3+ /Mn 3+ -Mn 4+ removes excess electrons from the Cu + sites via strong electronic interactions, preventing the reduction of Cu 2 O to metallic Cu 0 , which ensures the NF@CoMn 2 O 4 @Cu 2 O-Ag exhibits a high resistance to deactivation. The Cu + active sites of NF@CoMn 2 O 4 @Cu 2 O-Ag efficiently electroreduce CO 2 to the *CO atop intermediate, while the Ag active sites efficiently electroreduce CO 2 to the *CO bridge intermediate. The proximity of Cu + /Ag bimetallic sites shortens the distance for C-C bond coupling between the *CO atop and *CO bridge intermediates, facilitating the efficient electrocatalytic coupling of CO 2 to synthesize acetate. DFT analysis indicates that the ΔG required for C-C bond coupling on the short-distance Cu + /Ag bimetallic sites of NF@CoMn 2 O 4 @Cu 2 O-Ag is significantly lower than that of NF@CoMn 2 O 4 @Cu 2 O, enabling a high Faradaic efficiency of 64.97% for acetate production at -0.3 V vs. RHE. This study provides an effective strategy for the rational design of synergistic catalysis between heterometallic catalytic sites to efficiently achieve C-C coupling for the synthesis of C 2+ products.