Trace Single‐Atom Iron‐Decorated Nitrogen‐Doped Carbons Enable Highly Efficient Selective Oxidation of Ethyl Benzene

Abstract The hybridization of abundant transition metals with facile nitrogen‐doped carbons is an effective strategy to fabricate advanced functional materials for targeted applications. Herein, we demonstrate a novel and straightforward synthetic approach of preparing a series of different transition metal‐modified nitrogen‐doped carbons ( M /NC, M =Fe, Co, Ni) through the addition of corresponding metal sulfates during the polymerization of aniline, followed by high‐temperature (873–1273 K) pyrolysis treatment. While Fe/NC features predominantly single Fe atoms, nanoparticles of mixed metal oxides and or carbonates are formed on Co/NC and Ni/NC. When employed in the selective oxidation of ethyl benzene by using tert‐butyl hydroperoxide both as the solvent and the oxidant, these materials showed promoted catalytic response with the order of Fe>Co>Ni as compared with the metal‐free analogue. The performance can be further tuned by controlling the pyrolysis temperature, and the best performance can be achieved over Fe/NC‐1273 (0.153 wt.% Fe), affording an unprecedented acetophenone yield of 98 % and excellent cycling performance.