"DFT Comparison of N-Nitrosodimethylamine (NDMA) Decomposition Pathways Over Ni and Pd

V. A. RANEA; T. J. STRATHMANN; J. R. SHAPLEY; W. F. SCHNEIDER

CHEMCATCHEM

WILEY-V C H VERLAG GMBH

Año: 2011 vol. 3 p. 1 - 7

1867-3880

Recentexperimental studies report rapid and efficient reduction of Nnitrosodimethylamine(NDMA) and related aquatic micropollutantsmediated by palladium (Pd) and nickel (Ni) surfaces, butdiffering mechanisms have been reported for the surface reactions.Here, NDMA adsorption and fragmentation on Ni and Pdsurfaces has been studied using supercell slab density functionaltheory (DFT) calculations. NDMA adsorbs in two stableconfigurations on each surface. Upright binding through theNO fragment is slightly preferred energetically and providesentrance to an exothermic N-O dissociation pathway withmoderately high activation barriers. Flat binding through theNNO plane is somewhat less favorable but leads to a facile andexothermic dissociation across the N-N bond. These resultssuggest that both mechanisms are in competition and maycontribute to the observed catalytic reduction of NDMA overthese metals in aqueous solution