FeC nanoclusters integrated with Fe single-atom planted in nitrogen doped carbon derived from truncated hexahedron zeolitic imidazolate framework for the efficient transfer hydrogenation of halogenated nitrobenzenes.

The control of morphology, structure and composition of metal-organic frameworks derived metal-nitrogen doped porous carbon (M-N-C) with high precision and accuracy is essential for the catalytic performance. While single-atom or small-sized nanometer catalysts show notable effects in catalysis, one catalyst combining the advantages of single-atom and nanometer catalysts may cultivate more benefits. Herein, we designed and successfully fabricated a series of Fe-doped ZIF-x with different morphologies (cube→truncated hexahedron→truncated octahedron) in one pot by simply adjusting the adding amount of vitamin C. After high-temperature calcination, FeC integrated with Fe single-atom planted in N-doped carbon (Fe/Fe-N-C-x) with various morphology, structure and composition could be acquired. Among them, Fe/Fe-N-C-0.75 exhibited the best catalytic performance for the transfer hydrogenation of halogenated nitrobenzenes with NH·HO under room temperature. Acid-leaching tests, poisoning experiments, and the density functional theory calculations showed that FeC integrated with Fe single-atom had a better catalytic effect than the separated FeC or Fe single-atom.