Interaction of copper with the rhenium (101[overline]0) surface.

We have studied the adsorption of copper on the clean Re(101[overline]0) surface between 300 and 900 K by means of low- and medium-energy electron diffraction (LEED and MEED) and temperature-programmed thermal desorption (TPD). The persistence of a (1 × 1) LEED pattern during Cu deposition suggests the formation of pseudomorphic Cu islands. Accordingly, the intensity-voltage behaviour of the (1 × 1) LEED beams can be quantitatively superimposed by the coverage-weighed fractions of the I(V)-curves of uncovered Re areas and of Cu-covered (1 × 1) islands.

Model studies on CO oxidation catalyst systems: titania and gold nanoparticles.

The peculiar catalytic activity of Au-supported titanium dioxide surfaces in the CO oxidation reaction has been a focus of interest for more than twenty years. Herein, recent data concerning preparation and structural characterisation of planar catalyst model systems consisting of single-crystalline titania and/or gold nanoparticles deposited thereon is presented and reviewed. We first expand on the deposition and growth of TiO(2) films on selected metal host surfaces and then consider the deposition of Au nanoparticles on these surfaces, including information on their geometric and electronic structures.

Epitaxial growth of single-crystalline Al(2)O(3) films on Cr(2)O(3)(0001).

Thin, crystallographically oriented single-crystalline Al2O3 films can be grown epitaxially on Cr2O3(0001) by codeposition of Al vapor and O2 at a substrate temperature of 825 K. The properties and growth of these films were monitored by Auger electron spectroscopy (AES), low-energy electron diffraction (LEED), low-energy ion scattering (LEIS), and X-ray photoelectron spectroscopy (XPS). Two routes of preparation were investigated: (i) stepwise growth by alternating deposition of Al at room temperature and subsequent exposure to O2 at elevated temperatures; (ii) codeposition of Al and O2 at T > 800 K.