Synthesis and characterization of lead zirconate titanate powders obtained by the oxidant peroxo method

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Lead zirconate titanate (PbZr(1-x)TixO(3)) was synthesized by the "oxidant peroxo method (OPM)" with "x" between 0.25 and 0.50. Titanium metal was dissolved into a hydrogen peroxide/ammonia aqueous solution, followed by the addition of lead and zirconium nitrate solution. The amorphous precipitated precursor obtained was crystallized by heat treatment between 400 and 1000 degrees C. Images of transmission microscopy showed spherical particles with average diameter between 20 and 60 nm, and the presence of necks between particles treated at 700 degrees C. All of the impressed powders were characterized by X-ray diffractometry and FT-Raman spectroscopy. Powder samples with "x" up to 0.35 showed rhombohedral structure when treated at temperatures higher than 500 degrees C, and tetragonal structure when "x" was higher than 0.40. Analysis of XRD and Raman spectroscopy of the precursor powders showed amorphous-like structures, however powders treated at 400 degrees C showed a structure identified as an intermediate pyrochlore phase, independently of the Zr and Ti mole ratio. (C) 2008 Elsevier B.V. All rights reserved.