Co‐N‐C Catalysts Synthesized viaPyrolyzing the Ionic Liquids Solution Dissolved with Casein and Cobalt Porphyrin for Ethylbenzene Oxidation

Abstract In order to enhance the dispersion of active centers and decrease the size of metal particles, cobalt‐coordinated N‐doped carbon (Co‐N−C)with small particle size (3∼8 nm) were synthesized via pyrolyzing a special homogenous solution, namely the mixture of casein and cobalt porphyrin dissolved in 1‐butyl‐3‐methyllimidazolium chloride ionic liquid. And the catalysts have been characterized by N 2 adsorption‐desorption isotherm, XRD, TEM, XPS and so on. The asprepared Co‐N−C exhibiteda remarkable catalytic performance (conversion of ethylbenzene reached 35.3 %) with molecular oxygen as oxidant under solvent‐free conditions.Moreover, the best Co‐N−C showed superior cycling stability over 5 cycles. Those may be attributed to the well‐dispersed acitve sites with small particle size and powerful Co−N bond which effectively prevents metal particles from aggregation.