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

Electrochemical CO2 reduction reaction (CO2RR) for syngas production (mixture of H2 and CO) driven by renewable energy is a critical strategy to reduce carbon emission and for valorization of CO2. However, it remains a major challenge to robustly modulate the H2/CO ratio under the circumstance of voltage fluctuations. Herein, we prepare Co1-N-Ga1 atomic pairs confined in a nitrogen doping carbon substrate. Combined experimental and theoretical studies reveal that the orbital interactions involved in Co1 and Ga1 atomic pairs enable the synchronous optimizations of *COOH formation and splitting to CO, thereby balancing CO2RR and the hydrogen evolution reaction. In the flow cell, the dual-atom catalysts delivered tunable H2/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 cm2, the optimal catalyst maintains the desired H2/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.