Aspects of analysing supported catalysts by low-energy ion scattering

Low-energy ion scattering is very useful for the characterisation of suppor ted catalyst systems by providing information about the top layer elemental composition and near-surface composition profiles. Here Rh supported on Ti O2 and on SiO2 are investigated as model systems. Experimental results from the original and the encapsulated state are compared with simplified model calculations and with calculations using the elaborate computer codes MARL OWE and TRIDYN. Although a number of complicating physical effects are invo lved in the scattering and sputtering processes, useful interpretation of t he data is possible. (C) 2000 Elsevier Science B.V. All rights reserved.