Orbital Interactions in Co 1 -N-Ga 1 Atomic Pairs Tailor Syngas Composition from CO 2 Electroreduction for Downstream Upgrading Synthesis

Electrochemical CO 2 reduction reaction (CO 2 RR) for syngas production (mixture of H 2 and CO) driven by renewable energy is a critical strategy to reduce carbon emission and for valorization of CO 2 . However, it remains a major challenge to robustly modulate the H 2 /CO ratio under the circumstance of voltage fluctuations. Herein, we prepare Co 1 -N-Ga 1 atomic pairs confined in a nitrogen doping carbon substrate. Combined experimental and theoretical studies reveal that the orbital interactions involved in Co 1 and Ga 1 atomic pairs enable the synchronous optimizations of *COOH formation and splitting to CO, thereby balancing CO 2 RR and the hydrogen evolution reaction. In the flow cell, the dual-atom catalysts delivered tunable H 2 /CO ratios (0.5, 1, 2) at >300 mA cm −2 over a wide potential window of –0.6 to –1.1 V (versus the reversible hydrogen electrode). Furthermore, in a membrane electrode assembly electrolyzer of 100 cm 2, the optimal catalyst maintains the desired H 2 /CO ratios at 30 A total current with a syngas productivity of 12.4 L h −1 . Built on this, a tandem process involving electrocatalysis and thermocatalysis delivers the upgrading synthesis of methanol, ethanol, and acetic acid with corresponding selectivities of 86.7, 82.1, and 79.5%, respectively.