Study of the growth of CeO₂₂ nanoparticles onto titanate nanotubes

We report the study of the growth of CeO₂ nanoparticles on the external walls and Ce⁴⁺ intercalation within the titanate nanotubes. The materials were fully characterized by multiple techniques, such as: Raman spectroscopy, infrared spectroscopy (FTIR), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). The ion exchange processes in the titanate nanotubes were carried out using different concentrations of Ce⁴⁺ in aqueous solution. Our results indicate that the growth of CeO₂ nanoparticles grown mediated by the hydrolysis in the colloidal species of Ce and the attachment onto the titanate nanotubes happened and get it strongly anchored to the titanate nanotube surface by a simple electrostatic interaction between the nanoparticles and titanate nanotubes, which can explain the small size and even distribution of nanoparticles on titanate supports. It was demonstrated that it is possible to control the amount and size of CeO₂ nanoparticles onto the nanotube surface, the species of the Ce ions intercalated between the layers of titanate nanotubes, and the materials could be tuned for using in specific catalysis in according with the amount of CeO₂ nanoparticles, their oxygen vacancies/defects and the types of Ce species (Ce⁴⁺ or Ce³⁺) present into the nanotubes.