Solvent‐free selective oxidation of ethylbenzene with molecular oxygen catalyzed by cobalt catalysts supported on exfoliated carbon nitride

Abstract Exfoliated graphitic carbon nitride (eg‐C 3 N 4 ) material was applied as a support to load cobalt catalysts (CoO x /eg‐C 3 N 4 ) through a simple impregnation method. The physical and chemical properties of the synthesized CoO x /eg‐C 3 N 4 materials were characterized by a series of analytic techniques including XRD, SEM, FT‐IR, UV–vis, and XPS. The characterization results revealed that the introduction of Co 2+ species had not altered the graphitic structure of eg‐C 3 N 4 . The Co 2+ species probably coordinatively interact with the nitrogen‐containing group of eg‐C 3 N 4 . The catalytic performances of the CoO x /eg‐C 3 N 4 were evaluated in the solvent‐free selective oxidation of ethylbenzene (EB) using molecular oxygen as an oxidant. Among the 3CoO x /eg‐C 3 N 4 materials with various preparation temperatures, 3CoO x /eg‐C 3 N 4 ‐400 exhibited the highest EB conversion, which was owing to its superior percentages of Co 2+ and tertiary nitrogen species.