Spatially‐Directed C─C Coupling inside Three‐dimensional Metal‐organic Frameworks for CO ₂ Electroreduction to C ₂ Products

Abstract

Abstract The CO 2 electroreduction reaction to fuels and chemicals is a promising strategy for storing intermittent energy (such as sunlight and wind power) and closing the carbon cycle. Producing multi‐carbon oxygenates and hydrocarbons (C 2+ ) with broader applicability is highly desirable. However, the difficulty of the C─C coupling reaction hinders the conversion of CO 2 to C 2+ products with high energy input, low reaction rate, and poor selectivity. Here, we construct a three‐dimensional (3D) Fe‐quinoxalinedithiol (Fe‐QDT)‐based metal‐organic framework (MOF) featuring dual Fe sites within its ordered channel walls, enabling efficient interwall electrocatalysis for C 2 coupling reactions. We found that dual Fe sites can co‐catalyze the dimerization of *OCH 2 to *OCH 2 CH 2 O*, thus facilitating the generation of C 2 products. The free energy changes for the potential‐limiting steps in the electroreduction of C 2 species are −0.010 and 0.045 eV for CH 3 CH 2 OH and C 2 H 4 , respectively, which are significantly lower than those for other C 2 products. Consequently, the Fe‐QDT MOFs demonstrate high activity and selectivity in converting CO 2 to CH 3 CH 2 OH and C 2 H 4 . This work designs a novel and efficient active site for C─C coupling and provides valuable insights into the design principles of electrocatalysts for C 2 products.