Facile synthesis of TiO2:Eu~(3+) spindle shaped nanoparticles from titanate nanobelt precursors

摘要

Uniform TiO2:Eu~(3+) nanorods and spindle-shaped nanoparticles have been successfully prepared through simple calcination and two-step hydrothermal processes using titanate as the precursor. X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectrophotometer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and photoluminescence spectra (PL) were used to characterize these nanoparticles. On the basis of X-ray diffraction result, it can be assumed that the as-obtained precursors have the structure formula of titanate (H2Ti2O5·H2O). The as-formed nanotube precursors could transform to anatase TiO2:Eu~(3+) from nanotubes to nanorods and spindle-shaped nanoparticles with the calcination and hydrothermal processes. Under UV light excitation, both the TiO2:Eu~(3+) nanorods and spindle-shaped nanoparticles exhibit the strong red emission corresponding to the ~5D0-~7F2 transition of the Eu~(3+) ions. In addition, the luminescence properties of the as-obtained samples are dependent on the defects on the surface, leading to stronger luminescence intensity.