Cascade C─C/C─N Bonding for Acetamide Synthesis from Electrocatalytic CO₂ and Nitrate Coupling on CuCo Diatomic Sites.

Abstract

Electrocatalytic CO₂ coupling with nitrate to synthesize acetamide provides a promising way for the co-valorization of greenhouse gas and environmental pollutants. Aiming at generating acetamide via C─C─N bonding, a N-coordinated copper-cobalt diatomic catalytic sites is constructed to achieve CO₂ reduction to ketene intermediate and NO₃ ^- to ammonia, thereby facilitating the nucleophilic attack of *NH₂ on *CH₂CO to form acetamide. Based on the enhanced mass transfer of CO₂ in flow cell, an acetamide yield of 67.7 mg L^-1 and a FE of 15.1% are achieved over CuCo diatomic sites. In situ FT-IR, Raman spectroscopy, in situ XAFS combined with DFT suggest that CuCo diatomic pairs induce CO₂ and NO₃ ^- to stabilize on the catalytic surface via a favorable bridge adsorption configuration. And the electronic structure optimization promoted by interatomic electron interactions reduces the energy barriers for C─C and C─N bonding. This work achieves C─C─N bonding with ordered C─C and C─N coupling via diatomic sites, providing a novel strategy for the sustainable synthesis of acetamide.