Oxidation of Ethylbenzene to Acetophenone with N-Doped Graphene: Insight from Theory

A detailed theoretical study of the selective oxidation of ethylbenzene to acetophenone over nitrogen-doped graphene was carried out using methods rooted in density functional theory and two different models, based on periodic and cluster approaches. A comparison of these two models not only allows for an adequate choice of the cluster size, to have a more realistic model, but also clearly shows the local nature of the investigated reaction. The whole reaction pathway was characterized in terms of both intermediate structures and associated energies. The identified mechanism, in which the OOH radical is the active peroxide species that drives the reaction, is thermodynamically favorable due to the overall high exothermicithy. It is also kinetically favored since the formation of the hydroperoxyl radical and its decomposition in other active oxygen species are associated with low activation energies. Both results clearly underline the high catalytic activity of nitrogen-doped graphene toward this reaction.