Low-temperature chemical synthesis of lead zirconate titanate (PZT) powders free from halides and organics

A water-soluble peroxititanic complex [Ti(OH)(3)O-2](-) 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 degreesC 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 degreesC, revealing that the crystallization process starts at low temperature. Rhombohedral Pb(Zr0.60Ti0.40)O-3 was obtained at temperatures above 900 degreesC. 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.