title: Opposite face sensitivity of CeO₂ in hydrogenation and oxidation catalysis.
abstract: The determination of structure-performance relationships of ceria in heterogeneous reactions is enabled by the control of the crystal shape and morphology. Whereas the (100) surface, predominantly exposed in nanocubes, is optimal for CO oxidation, the (111) surface, prevalent in conventional polyhedral CeO2 particles, dominates in C2H2 hydrogenation. This result is attributed to the different oxygen vacancy chemistry on these facets. In contrast to oxidations, hydrogenations on CeO2 are favored over low-vacancy surfaces owing to the key role of oxygen on the stabilization of reactive intermediates. The catalytic behavior after ageing at high temperature confirms the inverse face sensitivity of the two reaction families.
authors.affiliation: Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich (Switzerland).
authors.forename: Gianvito
authors.initials: G
authors.lastname: Vilé
authors.forename: Sara
authors.initials: S
authors.lastname: Colussi
authors.forename: Frank
authors.initials: F
authors.lastname: Krumeich
authors.forename: Alessandro
authors.initials: A
authors.lastname: Trovarelli
authors.forename: Javier
authors.initials: J
authors.lastname: Pérez-Ramírez
keywords: ceria; crystal shape; hydrogenation; oxidation; structure sensitivity