Monatomic Co, CoO2, and CoO3 nanowires on Ir(100) and Pt(100) surfaces: Formation, structure, and energetics
Ferstl P, Mittendorfer F, Redinger J, Schneider MA, Hammer L (2017)
Publication Status: Published
Publication Type: Journal article, Original article
Publication year: 2017
Journal
Publisher: AMER PHYSICAL SOC
Book Volume: 96
Article Number: 085407
Journal Issue: 8
DOI: 10.1103/PhysRevB.96.085407
Abstract
In this study, we investigate the structural and chemical changes of monatomic CoO2 chains grown self-organized on the Ir(100) surface [P. Ferstl et al., Phys. Rev. Lett. 117, 046101 (2016)] and on Pt(100) under reducing and oxidizing conditions. By a combination of quantitative low-energy electron diffraction, scanning tunneling microscopy, and density functional theory we show that the cobalt oxide wires are completely reduced by H-2 at temperatures above 320 K and a 3 x 1 ordered Ir2Co or Pt2Co surface alloy is formed. Depending on temperature, the surface alloy on Ir(100) is either hydrogen covered (T < 400 K) or clean and eventually undergoes an irreversible order-disorder transition at about 570 K. The Pt2Co surface alloy disorders with the desorption of hydrogen, whereby Co submerges into subsurface sites. Vice versa, applying stronger oxidants than O-2 such as NO2 leads to the formation of CoO3 chains on Ir(100) in a 3 x 1 superstructure. On Pt(100), such a CoO3 phase could not be prepared so far, which, however, is due to the ultrahigh vacuum conditions of our experiments. As revealed by theory, this phase will become stable in a regime of higher pressure. In general, the structures can be reversibly switched on both surfaces using the respective agents O-2, NO2, and H-2.
Authors with CRIS profile
Pascal Ferstl
Lehrstuhl für Festkörperphysik
Alexander Schneider
Professur für Experimentalphysik
Lutz Hammer
Lehrstuhl für Festkörperphysik
Involved external institutions
Austria (AT)How to cite
APA:
Ferstl, P., Mittendorfer, F., Redinger, J., Schneider, M.A., & Hammer, L. (2017). Monatomic Co, CoO2, and CoO3 nanowires on Ir(100) and Pt(100) surfaces: Formation, structure, and energetics. Physical Review B, 96(8). https://doi.org/10.1103/PhysRevB.96.085407
MLA:
Ferstl, Pascal, et al. "Monatomic Co, CoO2, and CoO3 nanowires on Ir(100) and Pt(100) surfaces: Formation, structure, and energetics." Physical Review B 96.8 (2017).
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