Composition, structure and stability of surfaces formed by Ni deposition on Pd(111)

Jie Fu, Xiaofang Yang, Carl A. Menning, Jingguang G. Chen, Bruce E. Koel

Research output: Contribution to journalArticlepeer-review

2 Scopus citations

Abstract

Surface composition and structure of deposited Ni ultrathin films grown on a Pd(111) surface and their thermal stability have been studied using Auger electron spectroscopy (AES), X-ray photoelectron spectroscopy (XPS), low energy ion scattering (LEIS) and scanning tunneling microscopy (STM). In experiments where up to 2 monolayers (ML) of Ni was deposited onto Pd(111) at 300 K, the initial film growth followed a non-ideal layer-by-layer growth mode, in which the majority of the surface was covered by a single atomic layer of Ni, but the second Ni layer started to appear before the first layer was completed. Annealing the Ni/Pd(111) surface to 600 K caused Ni interdiffusion into subsurface layers and the outermost surface was mainly Pd. This structure, designated as Pd-Ni-Pd(111), was not stable in the presence of surface oxygen. Ni segregated to the topmost surface layer to form a (2 × 2) superstructure after exposing the Pd-Ni-Pd(111) surface at 590 K to 350 L O2. The oxygen-induced segregation of Ni is consistent with predictions from density functional theory (DFT) calculations.

Original languageEnglish (US)
Pages (from-to)56-64
Number of pages9
JournalSurface Science
Volume646
DOIs
StatePublished - Apr 2016

All Science Journal Classification (ASJC) codes

  • Condensed Matter Physics
  • Surfaces and Interfaces
  • Surfaces, Coatings and Films
  • Materials Chemistry

Keywords

  • Bimetallic surface
  • DFT
  • LEIS
  • STM
  • Subsurface monolayer
  • Surface segregation

Fingerprint Dive into the research topics of 'Composition, structure and stability of surfaces formed by Ni deposition on Pd(111)'. Together they form a unique fingerprint.

Cite this