Single crystalline CeO₂ nanotubes

Here, we report a facile synthetic methodology to prepare uniform single crystalline CeO₂ nanotubes through a hydrothermal transformation of CeO₂ nanorods in aqueous Ce(NO₃)₃ solution. A chemically driven etching-dissolution-deposition mechanism is proposed, involving the surface Ce³⁺ hydrolysis and dissolution at tips of nanorods and subsequent redeposition and crystallization on the outer sides of nanorods. Compared to CeO₂ nanorods, CeO₂ nanotubes exhibited the richer structural defects, higher reducibility and larger surface area, leading to a higher haloperoxidase-like activity.