title: Low-Temperature Disproportionation Reaction of NO on Au6-: A Mechanism Involving Three NO Molecules Promoted by the Negative Charge.
abstract: Conversion of NO to other nitrogen oxides is an elementary step in its catalytic removal processes. On coinage metal surfaces, two kinds of NO activation mechanisms have been well documented: the unimolecular dissociation of NO generates two adsorbed atoms, and the dissociation of an adsorbed (NO)2unit generates an adsorbed O and a free N2O. In this work, we observed a disproportionation mechanism involving three NO molecules on Au6-at a very low temperature (150 K), in which an adsorbed (NO)2reacts with a free NO forming an adsorbed NO2and a free N2O. The density functional theory (DFT) calculations indicated that this disproportionation step is significantly exothermic and has a very low activation barrier. The charge distributions on the involved cluster complexes and the correlation between the activity and the electronic properties of Au6-indicate the important role of extra negative charge in all reaction steps. The disproportionation mechanism revealed in this work could possibly exist in the NO removal processes on real gold catalysts.
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Jun
authors: J
authors: Ma
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Xizi
authors: X
authors: Cao
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Mengyi
authors: M
authors: Chen
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Baoqi
authors: B
authors: Yin
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Xiaopeng
authors: X
authors: Xing
authors: Shanghai Key Lab of Chemical Assessment and Sustainability, Department of Chemistry, Tongji University , 1239 Siping Road, Shanghai 200092, P. R. China.
authors: Xuefeng
authors: X
authors: Wang