Schematic structures (top view) of Pt-skin (111) surfaces with different amounts of Ni from pure Pt (a), subsurface Pt3Ni (b), and PtNi3 (c), to bulk Pt–Ni alloys (d), (e), and (f). The optimized lateral constants are given in brackets. The white and dark green spheres represent Pt and Ni atoms, and favorable adsorption sites are indicated by circles (for O and H) and triangle (CO), respectively.
Projected -band DOS of surface Pt atoms coordinated with adsorbates of different Pt–Ni surfaces. The energy reference is the Fermi level.
Calculated adsorption energies for CO (triangle), O (square), and H (circle) vs the center of -band on different surfaces, as defined in Fig. 1.
Calculated activation barriers for CO (square) and H (circle) oxidation vs oxygen adsorption energy on different surfaces, as defined in Fig. 1.
Calculated structures (top views) at TSs for CO oxidation on (a) and (b), and H oxidation on (c) and (d). The large white and dark green spheres represent for Pt and Ni atoms, while small white, middle purple, and gray spheres represent for H, C, and O, respectively.
Dependence of the calculated activation energies (in eV) for CO (square) and H (circle) oxidation on the bond length between reactants at TSs (in Å).
Calculated adsorption energies ( in eV) and adsorption sites of the CO, O, and H at a coverage of on different PtNi surfaces.
Calculated activation energies ( in eV) for and oxidation on different PtNi surfaces with unit cells.
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