Heterogeneous catalytic hydrogenation of nitroarenes is one of the most important chemical transformations, and exploring earth-abundant catalysts is very attractive for application. Herein, we studied the catalytic activity of several iron oxide catalysts with similar structure and surface area. It is found that γ-Fe 2 O 3 , α-Fe 2 O 3 , and FeO show obvious but a little limited activity, but the activity of the used catalyst is increased in the second run, especially for γ-Fe 2 O 3 . Characterization shows that Fe 2 O 3 is partly reduced with many oxygen vacancies produced on the surface, which accounts for the high hydrogenation activity. Finally, Fe 3 O 4 exhibits activity significantly higher than Fe 2 O 3 and FeO, and 100% selectivity in the hydrogenation of nitroarenes to anilines. Also, Fe 3 O 4 is easy to separate by a magnetic field and shows excellent recycling stability.

We report carbon can be activated as metal‐like hydrogenation catalyst for the selective hydrogenation of nitroarenes. Using DFT calculations we demonstrated the combination of P dopant and lattice defect in carbon can cause significant electron delocalization and change the band structure to a metal‐like one, and thus both H2 and the nitro group are easily activated for selective hydrogenation. Then we fabricated this carbon catalyst with tunable concentration of P dopant and lattice defects by polymerization and carbonization of phytic acid, and found the concentration of lattice defect is closely related to that of P‐dopants. The synthesized catalyst exhibits superior catalytic activity, perfect selectivity, and stability in the hydrogenation of nitroarenes, outperforming the reported metal‐free, metal‐oxide, and nickel catalysts. Importantly, the hydrogenation activity is linearly dependent on the P‐doping and/or defect concentration, perfectly agreeing with the DFT calculation. This work is expected to provide a cheap way for large‐scale production of anilines using metal‐like carbon catalyst.

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