Water Production Reaction on Rh(110)

By means of scanning tunneling microscopy and density functional theory calculations, we studied the water formation reaction on the Rh(110) surface when exposing the (2 × 1)p2mg-O structure to molecular hydrogen, characterizing each of the structures that form on the surface during the reaction. Fi...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:Journal of the American Chemical Society 2005-08, Vol.127 (32), p.11454-11459
Hauptverfasser: Africh, Cristina, Lin, Haiping, Corso, Martina, Esch, Friedrich, Rosei, Renzo, Hofer, Werner A, Comelli, Giovanni
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:By means of scanning tunneling microscopy and density functional theory calculations, we studied the water formation reaction on the Rh(110) surface when exposing the (2 × 1)p2mg-O structure to molecular hydrogen, characterizing each of the structures that form on the surface during the reaction. First the reaction propagates on the surface as a wave front, removing half of the initial oxygen atoms. The remaining 0.5 monolayers of O atoms rearrange in pairs, forming a c(2 × 4) structure. Second, as the reaction proceeds, areas of an intermediate structure with c(2 × 2) symmetry appear and grow at the expense of the c(2 × 4) phase, involving all the oxygen atoms present on the surface. Afterward, the c(2 × 2) islands shrink, indicating that complete hydrogenation occurs at their edges, leaving behind a clean rhodium substrate. Two possible models for the c(2 × 2) structure, where not only the arrangement but also the chemical identity is different, are given. The first one is a mixed H + O structure, while the second one resembles the half-dissociated water layer already proposed on other metal surfaces. In both models, the high local oxygen coverage is achieved by the formation of a hexagonal network of hydrogen bonds.
ISSN:0002-7863
1520-5126
DOI:10.1021/ja0524301