Constructing Asymmetric Cu Catalytic Sites for CO2 Electroreduction with Higher Selectivity to C2 Products.

The design of catalytic sites with tunable properties is considered a promising approach to advance the reduction of CO₂ into valuable fuels and chemicals, as well as to achieve carbon neutrality. However, significant challenges remain in precisely constructing catalytic sites to adjust target reduction products. In this study, catalysts were derived from metal-organic frameworks (MOFs) with different coordination environments during the electrochemical CO₂ reduction reaction (eCO₂RR), referred to as Cu-N₂O₂ and Cu-N₂O₃, respectively. Higher selectivity towards the production of C₂ products was exhibited by the Cu-N₂O₂-derived catalysts, characterized by asymmetric catalytic centers of Cu⁰ and Cu⁺, compared to the Cu-N₂O₃-derived catalysts, which contained only symmetric catalytic centers of Cu⁰ sites. This enhanced selectivity is attributed to the synergistic interaction between the Cu⁰ and Cu⁺ sites, facilitating the multi-electron transfer process and improving the activation of CO₂. This study explores how the coordination environment affects the catalytic performance of catalysts derived from MOFs, providing valuable insights for the development of more effective catalysts aimed at CO₂ reduction.