A highly active non-precious metal catalyst based on Fe-N-C@CNTs for nitroarene reduction

Research on transition metal-nitrogen-carbon (M-N-C) materials revealed their potential as catalysts in several important traditional reactions. However, the activity of M-N-C still needs to be further improved and the real active center of M-N-C catalysts is still under debate. In this work, an efficient Fe-N-C@CNTs for the hydrogenation of nitroarenes was prepared by pyrolysis of FeCl3, phenanthroline and CNTs. Fe-N-C supported on CNTs is much more active than that supported on activated carbon, showing the promotion effect of CNTs. The characterization results suggest that the high activity of Fe-N-C is mainly attributed to the formation of epsilon-Fe3N, which is the active site for the hydrogenation reaction. Nitrogen/carbon atoms contacted to the active centers could serve as bridges to transport the dissociated hydrogen atoms via spillover effect. The catalytic performance of Fe-N-C was also tested on fixed bed reactor under continuous flow condition for the first time and could smoothly catalyze the reaction for over 300 hours.