Depth profile analysis of strong metal - support interactions on Rh/TiO(2) model catalysts
Strong metal-support interactions (SMSI) are regarded to be responsible for the change in selectivity and activity of group 8 metal catalysts supported on transition metal oxides. To investigate the nature of interaction between the catalyst components, model systems for Rh/TiO(2) catalysts were prepared with a metal loading of the order of one monolayer on top of several hundred angstroms of TiO(2). The samples showed a sufficiently high electrical conductivity to be examined by low-energy ion scattering spectroscopy (ISS) and sputtering as well as by additional surface physical techniques. The model catalysts were annealed at several temperatures up to 823 K and depth profiles of the first atomic layers were measured after every step. The rhodium layer is encapsulated by an oxide layer at a substrate temperature of about 750 K, regardless of the presence or absence of hydrogen. The encapsulation cannot be reversed by an oxidation-reduction cycle.
Bibliographic Reference: Article: Nuclear Instruments and Methods in Physics Research B, Vol. 118 (1996), pp. 533-540
Record Number: 199611504 / Last updated on: 1997-01-16
Original language: en
Available languages: en