Morphological impact of manganese-cerium oxides on ethanol oxidation

The shape of nanoparticles alters their catalytic performance significantly, but the intrinsic chemical nature of this morphology-dependent phenomenon is still less understood. Here, we report that the morphology of MnOx-CeO2 nanomaterials that are enclosed by {100} and {111} facets considerably affected the reaction rate and the product selectivity in ethanol oxidation. Kinetic investigation revealed that the {100} and the {111} planes had very close apparent activation energies, indicative of the common manganese active species, but the specific reaction rate on the {100} plane was two times greater than that on the {111} plane because of the intrinsically higher oxygen storage capacity. These results evidence that morphology control of binary oxides at the nanometre level could promote their catalytic properties substantially.