Network-like (7v2 × v2)R45° surface reconstruction on rutile TiO2(001) by non-equilibrium self-organization

Anno: 1999

Autori: Nörenberg H., Dinelli F., Briggs G.A.D.

Affiliazione autori: University of Oxford, Department of Materials, Parks Road, Oxford OX1 3PH, United Kingdom

Abstract: A self-organized network structure has been discovered after annealing TiO2(001) rutile single crystals under non-equilibrium conditions. This novel structure appears after annealing under ultrahigh vacuum conditions to above 1000°C and subsequent quenching at a rate of approx. 100°C s(-1). The surface structure was investigated by scanning tunneling microscopy (STM) and reflection high-energy electron diffraction (RHEED). We observed one-dimensional structures running along the [110] and [110] directions, thus forming a two-dimensional network of ridges separated by 4nm. From atomically resolved STM images and RHEED observations, a two-domain (7v2 × v2)R45° surface reconstruction is concluded. The network formation requires a massive rearrangement of atoms starting from the initially epi-polished surface, suggesting that kinetic processes play a crucial role in establishing the network structure. After further annealing to 1500-1600°C the structure remains but the ridges appear fragmented, presumably as result of stress which is induced by deformation of the crystal after high-temperature annealing. Several factors such as readily available oxygen diffusing from the bulk to the surface, titanium diffusing from the surface to the bulk and a high surface energy of the (001) surface of TiO2 seem to favour the appearance of the network structure.

Giornale/Rivista: SURFACE SCIENCE

Volume: 436 (1-3)      Da Pagina: L635  A: L640

Parole chiavi: Scanning tunnelling microscopy (STM); Self-organization; Surface reconstruction; Titanium dioxide (Tio2)
DOI: 10.1016/S0039-6028(99)00718-9

Citazioni: 28
dati da “WEB OF SCIENCE” (of Thomson Reuters) aggiornati al: 2024-05-12
Riferimenti tratti da Isi Web of Knowledge: (solo abbonati)
Link per visualizzare la scheda su IsiWeb: Clicca qui
Link per visualizzare la citazioni su IsiWeb: Clicca qui