Nucleation and growth of Fe and FeO nanoparticles and films on Au(1 1 1)

• Published in: Surface science Vol. 602; no. 4; pp. 932 - 942
• Main Authors: Khan, Neetha A., Matranga, Christopher
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15-02-2008; Amsterdam Elsevier Science; New York, NY Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; IRON OXIDE; MATERIALS SCIENCE; Physics; SCANNING TUNNELING MICROSCOPY; Scanning tunneling microscopy (STM); STM; X-RAY PHOTOELECTRON SPECTROSCOPY; X-ray photoelectron spectroscopy (XPS); XPS; Iron oxide; Au; X-ray photoelectron spectroscopy (XPS); Scanning tunneling microscopy (STM); Scanning tunneling microscopy; Nucleation; Iron; Nanostructured materials; X-ray photoelectron spectra
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2007.12.027

We have studied the formation of Fe and FeO nanoparticles and thin films on the reconstructed Au(1
1
1) surface. Scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), and ion-scattering spectroscopy (ISS) were used to evaluate the structure and composition of Fe and FeO nanoparticles and films at different growth conditions. Iron grows as one monolayer high triangular particles on the Au(1
1
1) reconstruction. FeO was grown by exposing the Fe nanoparticles to molecular oxygen at 323
K, followed by annealing at 500–700
K. XPS results indicate that FeO is formed after room temperature oxidation. STM images show that well-ordered iron oxide particles form after annealing to 700
K. STM images also show evidence of a overlayer lattice with a short periodicity of 3.3
Å modulated by a larger periodicity of approximately 35
Å. The larger periodicity results from a moiré pattern formed between the iron oxide overlayer and the underlying Au(1
1
1) surface.