MC model studies of CeO 2 -metal interaction in Pt-Rh nanocatalysts

MC simulation technique has been used to investigate the effects of gradual reduction of Pt-Rh/ceria and the concomitant change in the metal-support interaction on the composition of Pt-Rh nanocatalysts. For all nanoparticle sizes the Pt fraction at the basal layer of the Pt 5 0 Rh 5 0 systems is found to increase with metal-support interaction. The Pt fraction is highest at the basal layer and reaches approximately the particle-average value of 50% at the fourth layer from the base. In the rest of the particle surface, which is exposed to the reacting gases, the Pt fraction is highest when metal-support interaction is weak; and decreases gradually with higher strength of metal-support interaction.