Abstract：

Atomically dispersed catalysts are widely adopted in CO₂ reduction reaction (CO₂RR) due to maximal atomic utilization and high catalytic activity. Dual-atom catalysts (DACs), with more dispersed active sites and distinct electronic structures compared with single-atom catalysts (SACs), may exhibit diverse catalytic performance. Herein, the DAC FeCo‒NC and SAC Fe‒NC/Co‒NC are employed as probes to explore DACs advantage in CO₂RR. Results show that the moderate interaction between the dual-atom center and N coordination balances structural stability and catalytic activity. CO is the only product on Fe‒NC/Co‒NC, and the high limiting potentials from -1.22 to -1.67 V inhibit further reduction. FeCo‒NC assisted with CO intermediate exhibits low limiting potentials of -0.64 V for both CH₃OH and CH₄, comparable to those on Cu-based catalysts. Under circumstance of applied potentials, CO₂RR on FeCo‒NC has greater advantages in yielding CH₃OH and CH₄ than that on Fe‒NC/Co‒NC, and hydrogen evolution reaction is severely inhibited. The intrinsic essence is that dual-atom center can provide large spin-polarization and multi-electron transfer capability, rendering CO intermediates as effective electronic and geometric modifiers in CO₂RR. This work highlights FeCo‒NC as a high-performance CO₂RR catalyst toward deep-reduction C1 products and elucidates CO intermediate assisted promotion mechanism via a dual-atom synergistic effect.