When used in catalysis, these conductive supports present clear differences with respect to activated carbon, and a recent theoretical study related to the interaction of transition metal atoms with CNT and graphite indicates major differences [23]. It has been demonstrated that the binding sites are depending on the structure of the support: the studies conducted over nickel show that the most stable anchoring sites vary sensibly between graphite and SWNT due to the different curvature of the surfaces where the active species can be deposited. The curvature also affects significantly the values of magnetic moments on the nickel atoms on the nanotube’s wall and the charge transfer direction between nickel and carbon can be inverted. Therefore, the possibility of peculiar metal–support interaction has to be taken into account.