DFT Investigation of the Adsorption/dissociation Mechanisms of Methyl Nitrite on the Pd(111) Surface

The adsorption behavior of methyl nitrite (MN) on the closed-packed Pd(111) surface has been investigated in detail by using density functional theory (DFT). MN binds to the surface in two alternative forms, using the nitrogen atom attached to the surface. An overall net charge transfer from the substrate to the cis-MN molecule is also confirmed. In addition, the reaction mechanism for the dissociation of MN on the Pd(111) surface has been identified and compared with the methanol decomposition via O-H scission. The results demonstrate that MN is a more active reactant than methanol for the oxidative addition to the Pd catalyst. The possible reason has been analyzed from the adsorption behaviors and reaction barriers, that is, MN is chemically absorbed on the Pd(111) surface; the CH3O-NO bond scission, leading to the formation of adsorbed methoxy species, is much more favorable than that of the O-H bond scission and has a large exothermic behavior.