Nitrogen Bicoupled Carbon Bonding for Electrocatalysis of CO₂ and Nitrobenzene via Engineering Hydroxyl Assisted Cobalt Single Atom

Abstract The coupling of CO₂ and nitrogen‐containing species nitrobenzene has become an appealing and sustainable strategy for synthesizing high‐valuable organic nitrides. However, how to realize the nitrogen bicoupled carbon bonding (C─N─C) between two CO₂ and nitrobenzene has been an insurmountable challenge. Hydroxyl‐assisted cobalt single atom (CoN₂O₂‐(OH)₂) is engineered to achieve C─N─C bonding for N, N‐dimethylaniline synthesis. The CO₂ is adsorbed through hydroxyl groups, that can be reduced and C─N coupling with nitrobenzene reduction intermediate on nearby Co site, and the vacant hydroxyl group continues to adsorb next CO₂, which is sequentially coupled with an intermediate of C─N coupling, achieving C─N─C bonding for synthesis N, N‐dimethylaniline. Herein, first, C─N─C bonding is achieved for green synthesis of N, N‐dimethylaniline via electrocatalytic reduction of nitrobenzene and CO₂ in an aqueous phase, with a yield of 505.2 µmol L⁻¹ h⁻¹ on CoN₂O₂‐(OH)₂. In situ characterizations and DFT calculations together demonstrated that the key of C─N─C bonding is that *PhNCH₃ intermediate of C─N bonding continues to couple with *CO achieving C─N─C bonding to generate *PhNCOCH₃ for N, N‐dimethylaniline synthesis with a much lower free energy is far easier to take place on CoN₂O₂‐(OH)₂. This work provides inspiring new insight into the green synthesis of long‐chain organic nitrides.