Abstract
Fully dispersed rhodium was supported on ceria with varying abundance of facets (100), (101) and (111). The resulting materials were evaluated for NO reduction by CO as well as CO/propylene oxidation under model and industrially relevant conditions. Very pronounced reactivity and stability differences were observed depending on the facet. Rh supported on (111) abundant ceria showed the highest activity and stability for all reactions. TPR and in-situ IR measurements revealed mechanistic details of NO reduction and CO oxidation, highlighting very different modes of interaction of Rh+3 ions on various facets and their contrasting reducibility, resulting in such pronounced catalytic activity changes.