Hydrothermal assisted sol-gel synthesis and multisite luminescent properties of anatase TiO2:Eu3+ nanorods

Uniform TiO2:Eu3+ spindlelike nanorods have been successfully prepared by a hydrothermal assisted sol-gel process with ethanediamine (ED) as the shape controller. A possible formation mechanism and luminescent properties were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence (PL) and kinetic decays. Site-selective spectroscopy was used to research into sites of Eu3+ in TiO2 lattice at 10 K, which identifies two kinds of sites of Eu3+ in TiO2 nanocrystals. One is located in the distorted lattice sites near the surface, and the other is situated in lattice sites with ordered crystalline environment. Moreover, the luminescence decay curve of products further proved the existence of multiple sites of Eu3+ ions in TiO2 nanocrystals.