Ion scattering and Auger electron spectroscopy analysis of alumina-supported rhodium model catalysts
Model systems for Rh/Al(2)O(3) catalysts were prepared by anodic oxidation of high-purity aluminium foils followed by subsequent vapour deposition of the noble metal. The alumina layer can be altered by a calcination procedure which leads to a strong increase of the layer thickness. The elemental depth distribution of the model catalysts is characterised by low-energy ion scattering spectroscopy and sputter-etching (ISS) with different primary energies. With Auger electron spectroscopy (AES), the sample composition is determined qualitatively as well as quantitatively. The noble metal loading found with AES is in agreement with the layer thickness measured by Rutherford backscattering spectroscopy (RBS). For the quantification of the metal layer thickness by AES, a layer-by-layer attenuation model is applied. The stoichiometry of the Al(2)O(3) layer is monitored with AES and RBS, showing an oxygen gradient from stoichiometric alumina to metallic Al, starting at a depth of only a few monolayers.
Bibliographic Reference: Article: Surface Science (1992) No. 275, pp. 101-113
Record Number: 199211581 / Last updated on: 1994-11-29
Original language: en
Available languages: en