Sp2- and sp3-hybridized carbon materials as catalysts for aerobic oxidation of cyclohexane

Abstract

The catalytic properties of sp2- and sp3-hybridized carbons, represented by graphene and diamond, in the selective oxidation of cyclohexane were investigated to understand the structure dependence of carbon materials in the reaction. sp2 carbons showed the higher activity than sp3 carbons. The highest activity was obtained over mesoporous graphene, a representative sp2-hybridized carbon, yielding a weight-normalized activity of 162.6 mmol g−1 h−1. The excellent performance of sp2 carbons was rationalized by their ability to catalyze the decomposition of peroxide intermediates, such as cyclohexyl hydroperoxide, which promoted the oxidative reaction to produce cyclohexanol and cyclohexanone.