Hydrothermal synthesis of acicular lead zirconate titanate (PZT)

The hydrothermal synthesis of lead zirconate titanate (PZT) powder with aci cular morphology using organic mineralizer, tetramethylammonium hydroxide p entahydrate (TMAH), has been investigated. The TMAH concentration and react ion time have a pronounced effect on the phase composition and morphology o f the resultant powders. At 150 degreesC phase pure PZT was obtained after 24 h in 0.5 m TMAH solution, and after 12 h in 1 m TMAH solution. TMAH conc entrations lower than 0.5 m do not produce the PZT phase. At all TMAH conce ntrations, the appearance of a fibrous intermediate phase, Zr-modified tetr agonal PX-phase PbTiO3 is observed at the early stage of the hydrothermal p rocess. Depending on the TMAH concentration, the intermediate either dissol ves to form cube-shaped PZT (TMAH concentrations of 1-4 m) or transforms in situ to acicular PZT powder using its fibrous morphology as a template (TM AH concentrations of 0.5-0.75 m). (C) 2001 Elsevier Science B.V. All rights reserved.