Preparation of lead titanate ultrafine powders from combined polymerisation and pyrolysis route

Lead titanate (PbTiO3) nanopowders were prepared from a monomeric metallo-organic precursor through combined solid-state polymerisation and pyrolysis (CPP). This makes it possible to adjust the mean particle size in a wide range by just choosing the appropriate reaction temperature. This particular preparation route was studied by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The size effects in the resulting PbTiO3 nanopowders were investigated by standard methods such as X-ray diffraction (XRD) and FT-Raman spectroscopy. By using the double Voigt method in analysing the XRD results, smaller mean particle size and narrower size distributions were found for powders prepared at lower reaction temperatures, with the tetragonality being reduced. Preliminary electron paramagnetic resonance (EPR) measurements demonstrate that paramagnetic chromium probe ions incorporate very well into the PbTiO3 lattice, particularly enabling corresponding high-field EPR measurements which have proven exceedingly informative in our previous investigations on Mn2+-doped barium titanate (BaTiO3) nanopowders. Moreover, the potential of the CPP route is enhanced to prepare perovskitic stoichiometric solutions for advanced practical applications. (C) 2003 Kluwer Academic Publishers.