Direct oxygen-containing simulated flue gas electrolysis over amine-confined Ag catalyst in a flow cell

High cost of pure CO 2 feed constitutes a significant economic obstacle in industrial-scale CO 2 electrolysis. Direct CO 2 electrochemical conversion from flue gas has emerged as a promising strategy to reduce feed cost, while the O 2 in flue gas cannot be ignored due to its strong reactivity. Here, we achieved fast, selective CO electrosynthesis directly fed with simulated oxygen-containing flue gas (95% CO 2 +5% O 2 ) over the amine-confined Ag catalysts in a flow cell, among which dimethylamine-modified Ag exhibited 80.6% CO Faradaic efficiency with partial current density of 333.7 mA cm −2 . In situ spectroscopy demonstrated that dimethylamine confinement endows a robust CO 2 adsorption-conversion capacity. Theoretical calculations further elucidated that amine modification could not only mediate CO 2 adsorption and ∗COOH intermediate formation but could also block the ∗OOH intermediate pathway in the side reaction of oxygen reduction. These findings pave a new avenue for rational design of amine-confined electrocatalysts for direct flue gas conversion and utilization.