Preparation and phase transformation of anatase-rutile crystals in metal doped TiO2/muscovite nanocomposites

Nanometer titanium dioxide (TiO2) films were deposited on muscovite flakes and doped with a number of different metal ions (Al3+, Sn4+, Fe3+, Cu2+, Co2+, Mn2+ or Zn2+) using a chemical liquid deposition method. The morphology and the anatase-rutile (A-R) transformation were studied by scanning electronic microscopy (SEM) and X-ray diffraction (XRD), respectively. Apart from round particles, SEM micrographs show that euhedral pillar rutile grains are found in the samples doped with Fe3+, Mn2+ or Zn2+ ions. The rutile phase of TiO2 thin layers on muscovite could be generated at low temperature, 60 degrees C. The XRD results confirm that the addition of metal ions affects the anatase-rutile (A-R) transformation. The Mn2+, Sn4+, Fe3+ and Zn2+ ions promote the A-R transformation while the Al3+, Cu2+ and Co2+ ions inhibit the A-R transformation of TiO2 thin layers on muscovite. The influence of metal ion doping on the A-R transformation of the TiO2 thin layers on muscovite depends on the substitution of foreign ions for Ti4+ ions in TiO2 thin layers. (c) 2005 Elsevier B.V. All rights reserved.