Titanium and reduced titania overlayers on titanium dioxide(110)

doi:10.1016/0368-2048(94)02258-5

Journal of Electron Spectroscopy and Related Phenomena

Volume 73, Issue 1, 31 May 1995, Pages 1-11

https://doi.org/10.1016/0368-2048(94)02258-5 Get rights and content

Abstract

The adsorption of titanium on titanium dioxide TiO₂(110) has been studied by X-ray photoelectron spectroscopy (XPS) and low energy ion scattering (LEIS). The XPS data for Ti overlayers are interpreted using peak fitting based on experimental standard spectra. 4 Å of Ti deposited at 150 K reacts with the substrate to produce ≈ 12 Å of intermediate oxidation state Ti. Adsorption of neutral metal begins on top of this interface oxide film, but 20 Å of deposited Ti are needed to cover the oxide completely. LEIS data indicate a tendency for clustering of Ti on top of the interface oxide. Ar⁺ sputtering of stoichiometric TiO₂ leads to preferential loss of O from the near surface region. This reduction of the clean, annealed oxide surface by Ar⁺ ion bombardment starts immediately and does not reach a steady state until 3 × 10¹⁷ ions cm⁻², at which point the reduced overlayer is 17 Å thick.

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Titanium and reduced titania overlayers on titanium dioxide(110)

Abstract

Adv. Catal.

Prog. Surf. Sci.

Prog. Solid State Chem.

Surf. Sci.

Surf. Sci.

Surf. Sci.

Surf. Sci.

Surf. Sci.

J. Phys. Chem. Solids

Surf. Sci.

Surf. Sci.

Surf. Sci.

Appl. Surf. Sci.

J. Phys. Chem. Solids

J. Vac. Sci. Technol. A

Nucl. Instrum. Methods, Sect. B

Surf. Sci.

Phys. Rev. B

Surf. Sci.

Surf. Sci.

Langmuir

Phys. Rev. B