| AVS 55th International Symposium & Exhibition | |
| Surface Science | Wednesday Sessions |
| Session SS1-WeA |
| Session: | Structure of Oxide Surfaces and Oxide Heterostructures |
| Presenter: | A. Birkner, Ruhr-Universität Bochum, Germany |
| Authors: | A. Birkner, Ruhr-Universität Bochum, Germany V. Schott, Ruhr-Universität Bochum, Germany Z. Wang, Ruhr-Universität Bochum, Germany Ch. Wöll, Ruhr-Universität Bochum, Germany |
| Correspondent: | Click to Email |
The investigation of Cu deposits on ZnO substrates is of significant importance for understanding methanol synthesis using Cu/ZnO/Al2O3 catalysts. The role of the Cu is still under debate. Whereas some authors propose that the active sites are on the surface of bare Cu particles, others suggest that under reaction condition the surface in fact is covered by a thin layer of ZnO. In order to resolve this issue we have investigated temperature induced morphology changes of Cu islands deposited on ZnO substrates. We have extended the STM investigations of Kroll and Köhler1 by additionally employing scanning electron microscopy (SEM). Our combined SEM/STM instrument allows to investigate Cu nanoparticles directly after deposition and heating and after exposure to reactants at pressures up to 1 bar. With the help of the SEM the very same Cu particle can be addressed before and after gas-phase exposure. By additionally employing Auger spectroscopy we can determine the composition of the surfaces of the Cu particles. We will also present first STM measurements of Cu clusters deposited on ZnO powder particles.
1 M. Kroll, U. Köhler, Surf. Sci. 601 (2007) 2182.