Formation of anatase TiO₂ nanoparticles by simple polymer gel technique and their properties

Pure anatase nano-TiO₂ powders were successfully prepared by a simple polymer gel technique using poly-(vinylpyrrolidone) (PVP) as the polymer. The products were systematically characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), field-emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), UV–visible spectroscopy and photoluminescence studies. The XRD and XPS results indicate that the prepared powder had a pure anatase nano-TiO₂ structure with lattice parameters a and c of 0.378 and 0.951nm, respectively. The particle size analysed by TEM ranged between 7 and 12nm. The maximum UV absorption for the TiO₂ nanoparticles was below 400nm with an estimated direct band gap (Eg) of 3.55eV. The photoluminescence peaks of the nanopowder were observed at 391 and 468nm. The nanosized materials were produced using a simple and cost effective polymer gel technique.