Formamide Electrosynthesis on a Ag1Cu Single-Atom Alloy

Abstract Electrochemical co-reduction of NO3− and CO2 to formamide (ENCF) offers a promising route for eco-friendly formamide synthesis. Herein, we propose a holistic strategy for highly efficient and sustainable ENCF. A Ag1Cu single-atom alloy is designed and used as a powerful catalyst. We construct an integrated system comprising upstream plasma-driven air-to-NOx− conversion with downstream cathodic ENCF and anodic glycerol oxidation. This integrated system achieves an exceptional formamide yield rate of 82.15 mmol h−1 g−1 and a Faradaic efficiency of 62.64%, as well as a long-term stability for 200 h of electrolysis. Mechanistic investigations unravel that Ag1Cu catalyzes ENCF via a dual-site mechanism, in which the Ag1 site activates CO2 to *CHO and the Cu site activates NO3− to *NH2, while the Ag1 site further promotes *CHO–*NH2 coupling for selective formamide generation. Our work demonstrates a carbon-neutral and energy-efficient pathway for the synthesis of value-added amides and related organonitrogen chemicals.