▎ 摘　　要

Results of first-principles modeling of interactions of graphene and graphite with iron impurities predict the colossal difference between these two carbon allotropes. Insertion of the iron atoms between the planes of graphite is much more energetically favorable than adsorption of the iron ad atom at the graphite or graphene surface. High mobility of iron ad atom over graphite surface and within bulk graphite is reported. Calculated values of formation energies for the substitutional iron impurities suggest that iron is more destructive for graphite than for graphene. This effect caused formation of a uniform carbon environment of the iron atom inside the multilayer system. In contrast to graphene, segregation of the substitutional iron impurities in graphite under ambient conditions is not energetically favorable. Enhancement of interlayer bonding in contaminated graphite and purity of graphene from iron impurities are also reported. (C) 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim