First-principles calculations and XPS measurements of gold segregation at the Cu3Au(111) surface

Abstract

Articles you may be interested inEffect of gold subsurface layer on the surface activity and segregation in Pt/Au/Pt3M (where M = 3d transition metals) alloy catalyst from first-principles J. Chem. Phys. 142, 034707 (2015); 10.1063/1.4905919Catalytic activity of Pd ensembles over Au(111) surface for CO oxidation: A first-principles study Position of segregated Al atoms and the work function: Experimental low energy electron diffraction intensity analysis and first-principles calculation of the ( √ 3 × √ 3 ) R 30 ° superlattice phase on the (111) surface of a Cu -9 at. % Al alloy A combination of first-principles calculations based on density-functional theory, pseudopotentials, and x-ray photoelectron spectroscopy (XPS) measurements is used in order to study Au segregation in Cu 3 Au(111) surfaces. Our theoretical results suggest Au compositions from 50% to 75% in the topmost layer, depending on the chemical potentials of the atomic species. This strong Au segregation is restricted to the topmost surface plane and it is supported by the XPS measurements in a semiquantitative manner.

A versatile platform for graphene nanoribbon synthesis, electronic decoupling, and spin polarized measurements

“…The image clearly reveals the straight 7-AGNR structure corresponding to the nanoribbon formation on Au(111) 1 in contrast to the growth of partially chiral nanoribbons from DBBA on Cu(111). 17 We tentatively attribute this behavior to: (1) a vertical relaxation of Au atoms of the surface layer above the Cu atoms, 37 exposing them more for Ullmann coupling reactions, and (2) a signicant enrichment of the surface layer by Au atoms compared to the ideal Cu 3 Au(111) surface. 30 In addition to pristine 7-AGNRs, we also observe the spontaneous growth of defective ribbons (Fig.…”