Theoretical Study on Nitrobenzene Hydrogenation by N-Doped Carbon-Supported Late Transition Metal Single-Atom Catalysts

A density functional theory (DFT) study was performed to investigate the activities of 12 late transition metal single-atom-supported nitrogen-doped carbon-based catalysts (M-1-N-4/C SACs) nitrobenzene hydrogenation. Three different dihydrogen (H-2) dissociation mechanisms are proposed: homolytic cleavage at the metal (M) site, heterolytic cleavage at M-N sites, and heterolytic cleavage at M-N-C sites. The coadsorption of nitrobenzene (PhNO2) and H2 was proposed, and the effect of charge change of hydrogen atoms caused by the coverage of PhNO2 on the H-2 dissociation activity was revealed. Six M-1-N-4/C SACs (M = Ru, Os, Fe, Ag, Ir, Rh) with a potentially high activity of H-2 dissociation were screened. Then, the two crucial steps, H2 dissociation and the second N-O bond breaking (PhNOH* + H*. PhN* + H2O), were compared. The obtained results indicate that different M-1-N-4/C SACs might have different rate-determining steps for nitrobenzene hydrogenation and that Ru-1-N-4/C SAC could be one of the most promising catalysts with good catalytic activities for nitrobenzene hydrogenation.

Automated summary

This study investigates the activities of 12 late transition metal single-atom-supported nitrogen-doped carbon-based catalysts in nitrobenzene hydrogenation. The results indicate that Ru-1-N-4/C SAC could be one of the most promising catalysts with good catalytic activities for nitrobenzene hydrogenation.