Adsorption and reaction of NO2 on a (√3×√3)R30° Sn/Pt(111) surface alloy

Intermediates and Spectators in O2Dissociation at the RuO2(110) Surface

“…Higher chemical potential regions can be accessed with other oxidant gases. For instance, NO 2 dosing is a common means of adding O to a metal surface, , through the reaction NO 2 false( normalg false) ⇌ NO false( normalg false) + O* The oxygen chemical potential is then given by Δ μ O = μ NO 2 ( T , P ) − μ NO ( T , P ) − 1 2 E O 2 = μ NO 2 ° ( T ) − μ NO ° ( T ) − 1 2 E O 2 + R T ln false( P NO 2 / P NO false) The standard state chemical potentials can be evaluated ...…”

“…Higher chemical potential regions can be accessed with other oxidant gases. For instance, NO 2 dosing is a common means of adding O to a metal surface, 47,48 through the reaction The oxygen chemical potential is then given by 46 The standard state chemical potentials can be evaluated straightforwardly from DFT results, and the accessible range of ∆µ O becomes bound only by the accessible ratio of NO 2 to NO pressures. Figure 5a indicates with an arrow near 0.76 eV the ∆µ O in a 10 5 excess of NO 2 over NO at 300 K. At these conditions, bridge-site O 2 * are clearly thermodynamically stable and cus-site O 2 * nearly so.…”

Review of Pt-Based Bimetallic Catalysis: From Model Surfaces to Supported Catalysts

“…Procedures for the preparation of bimetallic surface structures under UHV conditions have been described in detail previously. 27,28 For example, when a 3d transition metal is deposited onto a Pt (111) surface at 300 K, the 3d atoms stay on the topmost layer to produce the 3d−Pt−Pt (111) surface configuration. If this surface is subsequently heated to 600 K, or if the monolayer deposition of the 3d metal occurs with the Pt (111) substrate held at 600 K, most of the 3d atoms diffuse into the subsurface region to produce the Pt−3d−Pt (111) subsurface structure.…”

“…27,28 For example, when a 3d transition metal is deposited onto a Pt (111) surface at 300 K, the 3d atoms stay on the topmost layer to produce the 3d−Pt−Pt (111) surface configuration. If this surface is subsequently heated to 600 K, or if the monolayer deposition of the 3d metal occurs with the Pt (111) substrate held at 600 K, most of the 3d atoms diffuse into the subsurface region to produce the Pt−3d−Pt (111) subsurface structure. As shown in Figure 2, monolayer bimetallic surfaces can have three idealized configurations: a surface 3d−Pt−Pt (111) configuration, where the metal monolayer grows epitaxially on the surface of the Pt substrate; an intermixed configuration, where the 3d atoms reside in the first two Pt layers to some varying degree; and the subsurface Pt−3d−Pt (111) configuration, where the first layer is composed of Pt atoms and the second layer consists of the 3d atoms.…”

Low Temperature H2O and NO2 Coadsorption on θ-Al2O3/NiAl(100) Ultrathin Films

“…For this purpose, well-defined model catalyst systems serve as a convenient platform to study NO 2 , H 2 O, and NO 2 +H 2 O layers at low temperatures. A majority of the previous surface science studies on model catalysts were performed on metallic surfaces such as Au(111), [5][6][7][8][9] polycrystalline Au, 10 polycrystalline Cu, 11 polycrystalline Ni, 12 W(110), 13 Pt(111), 14 Pt(100), 15 Sn/Pt(111), 16 Rh(111)-Rh/Pd(111), 17 Ag(111), [18][19][20][21][22][23] and Ag(110). 24 In contrast to the metallic systems, there exists only a limited number of surface science studies focusing on the interaction of adsorbed NO 2 + H 2 O layers on metal oxide surfaces in the literature.…”