Molecular-level Modulation of N, S-Co-Doped Mesoporous Carbon Nanospheres for Selective Aqueous Catalytic Oxidation of Ethylbenzene

Selective oxidation of aromatic alkanes into high value-added products through benzylic C-H bond activation is one of the main reactions in chemical industry. On account of the constantly increasing demand for mass production, efficient, eco-friendly and sustainable catalysts are urgently needed. Herein, we describe a facile and versatile emulsion-assisted interface self-assembly strategy towards molecular-level fabrication of co-doped mesoporous carbon nanospheres with controllable active N and S species. The method enables a high degree of control over nanoparticle sizes, mesoporous nanostructures, contents of heteroatoms and the chemical composition. The optimized catalyst exhibits high catalytic performance of 97 % ethylbenzene conversion and 98 % selectivity to acetophenone. Density functional theory simulations reveal that N, S-co-doping leads to the redistribution of charge and spin densities, introducing more active carbon atoms and realizing aerobic oxidation of ethylbenzene efficiently. This work presents a general strategy for molecular-level design of carbon-based catalysts, and also provides new insight into the influence of heteroatom-doping on catalytic properties.