Opposite face sensitivity of CeO₂ in hydrogenation and oxidation catalysis

Gianvito Vilé; Sara Colussi; Frank Krumeich; Alessandro Trovarelli; Javier Pérez-Ramírez

doi:10.1002/anie.201406637

Opposite face sensitivity of CeO₂ in hydrogenation and oxidation catalysis

Angew Chem Int Ed Engl. 2014 Nov 3;53(45):12069-72. doi: 10.1002/anie.201406637. Epub 2014 Aug 21.

Authors

Gianvito Vilé¹, Sara Colussi, Frank Krumeich, Alessandro Trovarelli, Javier Pérez-Ramírez

Affiliation

¹ Institute for Chemical and Bioengineering, Department of Chemistry and Applied Biosciences, ETH Zurich, Vladimir-Prelog-Weg 1, 8093 Zurich (Switzerland).

PMID: 25146728
DOI: 10.1002/anie.201406637

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.

Keywords: ceria; crystal shape; hydrogenation; oxidation; structure sensitivity.