Structural characterization and chemical reactivity of dual doped graphene

Herein, we employed first-principle calculations to study the structure and reactivity of dual-doped graphene. The new materials were derived from graphene by replacing two carbon atoms with one 2p element (B, N or O), and one 3p element (Al, Si, P or S). A total of 12 dual-doped graphenes were used to perform a comparative study and identify the most promising materials for the development of new catalysts and anchoring nanoparticles. The structural analysis indicated that in all cases, except SiB, the dopants prefer to replace a CC bond. Yet, not always the dopants are bonded, presenting an edge-like bonding. As regards chemical reactivity, in general the introduction of two atoms remarkably increases reactivity as compared to graphene. The most prominent examples are Al–O, S–N, P–O and Si–B(para) codoped graphene which present reactivity higher than perfect and monodoped graphenes. This effect was attributed to the strong charge redistribution induced by the dopants. In most cases the heteroatoms are the most reactive sites, but in others the carbon atoms are more reactive, as in Al–O and Si–B codoped graphene. The combination of 2p and 3p dopants offers the possibility of adjusting over a wide range the reactivity of graphene.