Design of Co-Cu Diatomic Site Catalysts for High-efficiency Synergistic CO 2 Electroreduction at Industrial-level Current Density.

Single atom catalysts (SACs) have been widely studied in the field of CO 2 electroreduction, but industrial-level current density and near-unity product selectivity are still difficult to achieve. Herein, a diatomic site catalysts (DASCs) consisting of Co-Cu hetero-diatomic pairs is synthesized. The CoCu DASC exhibits excellent selectivity with the maximum CO Faradaic efficiency of 99.1 %. The CO selectivity can maintain above 95 % over a wide current density range from 100 mA cm -2 to 500 mA cm -2 . The maximum CO partial current density can reach to 483 mA cm -2 in flow cell, far exceed industrial-level current density requirements (>200 mA cm -2 ). Theoretical calculation reveals that the synergistic catalysis of the Co-Cu bimetallic sites reduce the activation energy and promote the formation of intermediate *COOH. This work shows that the introduction of another metal atom into SACs can significantly affect the electronic structure and then enhance the catalytic activity of SACs.