Ligand-free Self-Assembly of Ceria Nanocrystals into Nanorods by Oriented Attachment at Low Temperature

Abstract

Single-crystalline ceria nanorods have been fabricated by self-assembly of ceria nanocrystals via a simple, low-temperature, and ligand-free approach. Detailed high-resolution transmission electron microscopy shows that the nanorods are formed along the [211] or [110] direction by self-organization of truncated octahedral ceria nanocrystals, sharing the {111} or {200} planes with each other, whereas the previous report shows that only the [110] direction exists in ceria nanorods. The nucleation temperature and molar ratio of Ce3+ and OH- also play key roles in the formation of ceria nanorods. Moreover, the formation mechanism was explained in detail.