A water-soluble peroxititanic complex [Ti(OH)3O2]- was prepared through the reaction between titanium metal and hydrogen peroxide at pH = 11. A solution of lead nitrate and zirconyl nitrate was added to the peroxititanic acid solution, and a stoichiometric and amorphous precipitate of a mixed oxide of lead, zirconium and titanium was formed, which was filtered off and washed to eliminate nitrate ions. The precipitate was calcined between 600 and 1000°C using a closed alumina boat. The precipitate was characterized by TG-DTA, ICP (Pb, Zr and Ti), elemental analysis (C, H, N and O), Raman spectroscopy and X-ray diffraction (XRD), and the calcined PZT powders were characterized by Raman spectroscopy and XRD. The amorphous precipitate showed a weight loss of 26% in the range from 30 to 500°C, revealing that the crystallization process starts at low temperature. Rhombohedral Pb(Zr0.60Ti0.40)O3 was obtained at temperatures above 900°C. It is of particular importance that the use of the peroxititanic complex provided a method to synthesize PZT powders without the use of any organics (including alkoxides) or reagents containing undesirable halides.
ASJC Scopus subject areas
- Materials Chemistry