Single-atom cobalt catalysts for chemoselective hydrogenation of nitroarenes to anilines

• Published in: Chinese chemical letters 2023-12, Vol.34 (12), p.108745-188, Article 108745
• Main Authors: Liu, Xiaochun, Wang, Chaoyue, Meng, Jiaolong, Yue, Xiaodong, Wang, Qingyun, Lu, Jiatian, Wang, Junke, Wang, Xicun, Zong, Yingxiao, Jiang, Xuefeng
• Format: Article
• Language: English
• Subjects: Chemoselective hydrogenation; Cobalt catalyst; Heterogeneous catalysis; Nitro reduction; Single-atom catalysts
• ISSN: 1001-8417; 1878-5964
• DOI: 10.1016/j.cclet.2023.108745

Single-atomic catalysts (SACs) caught considerable attention due to their unique structural properties, complete exposed active site, and 100% atom utilization efficiency with remarkable catalytic activity. Mesoporous single-atomic cobalt catalyst with Co-N4 active sites was synthesized by using nitrogen-doped graphene derived from acrylonitrile. Single-atomic cobalt was observed by aberration-corrected high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) in Co@Nx-C-800. Notably, the density functional theory (DFT) calculation and the extended X-ray absorption fine structures (EXAFS) fitting results indicate that the coordination structure of Co-N is four-coordinated. In this work, the practical hydrogenation of nitroarenes to anilines enabled by Co@Nx-C-800 was established with excellent yields and selectivity, which proved its advantages and potential applications. [Display omitted] Acrylonitrile-derived nitrogen-doped carbon-supported mesoporous single-atom cobalt catalyst was prepared by polymerization pyrolysis and pickling, which can efficiently reduce nitroarenes to the amine compounds with H2 and can be recycled seven times without obvious catalytic activity loss. Both the DFT calculation and the EXAFS fitting results indicate that the Co−N coordination number is 4, which is favorable to the lowest dissociation energy and the highest adsorption energy of H2.