Morphology-dependent redox and catalytic properties of CeO2 nanostructures: Nanowires, nanorods and nanoparticles

The redox features and the catalytic activities of ceria nanowires, nanorods and nanoparticles were comparatively studied. The morphology-dependent phenomenon is closely related to the nature of the exposed crystal planes. The CeO2 nanoparticles mainly expose the stable {1 1 1} plane on the surface, whereas the rod-shaped nanostructures preferentially expose the reactive {1 1 0} and {1 0 0} planes, giving higher oxygen storage capacity and catalytic activity for CO oxidation. Although both the CeO2 nanorods and the CeO2 nanowires predominantly expose the reactive {1 1 0} and {1 0 0} planes, the CeO2 nanowires favor to expose a large proportion of active planes on the surface, resulting in a much higher activity for CO oxidation than the nanorods.