Water-induced surface reconstruction of oxygen (2x1) covered Ru(0001)

Maier S, Cabrera-Sanfelix P, Stass I, Sánchez-Portal D, Arnau A, Salmeron M (2010)

Publication Status: Published

Publication Type: Journal article

Publication year: 2010

Journal

Physical Review B American Physical Society

Publisher: AMER PHYSICAL SOC

Book Volume: 82

Journal Issue: 7

URI: https://journals.aps.org/prb/abstract/10.1103/PhysRevB.82.075421

DOI: 10.1103/PhysRevB.82.075421

Abstract

Low-temperature scanning tunneling microscopy and density-functional theory (DFT) were used to study the adsorption of water on a Ru(0001) surface covered with half monolayer of oxygen. The oxygen atoms occupy hcp sites in an ordered structure with (2x1) periodicity. DFT predicts that water is weakly bound to the unmodified surface, 86 meV compared to the similar to 200 meV water-water H bond. Instead, we found that water adsorption causes a shift of half of the oxygen atoms from hcp sites to fcc sites, creating a honeycomb structure where water molecules bind strongly to the exposed Ru atoms. The energy cost of reconstructing the oxygen overlayer, around 230 meV per displaced oxygen atom, is more than compensated by the larger adsorption energy of water on the newly exposed Ru atoms. Water forms hydrogen bonds with the fcc O atoms in a (4x2) superstructure due to alternating orientations of the molecules. Heating to 185 K results in the complete desorption of the water layer, leaving behind the oxygen-honeycomb structure, which is metastable relative to the original (2x1). This stable structure is not recovered until after heating to temperatures close to 260 K.

Authors with CRIS profile

Sabine Maier Professur für Experimentalphysik (Rastersondenmikroskopie)

Involved external institutions

Donostia International Physics Center (DIPC) ES Spain (ES)

How to cite

APA:

Maier, S., Cabrera-Sanfelix, P., Stass, I., Sánchez-Portal, D., Arnau, A., & Salmeron, M. (2010). Water-induced surface reconstruction of oxygen (2x1) covered Ru(0001). Physical Review B, 82(7). https://dx.doi.org/10.1103/PhysRevB.82.075421

MLA:

Maier, Sabine, et al. "Water-induced surface reconstruction of oxygen (2x1) covered Ru(0001)." Physical Review B 82.7 (2010).

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