Seeding Effects in the Sol-Gel Preparation of Lead Zirconate Titanate (PZT) Powders

Lead zirconate titanate, Pb(Zr, Ti)O₃ (PZT), crystallizes in a perovskite form from an intermediate pyrochlore phase and the effects of the presence of perovskite seeds have been considered. PZT powders have been obtained from lead acetate and Zr and Ti alkoxides using a sol-gel process involving a chemical modification by acetylacetone. Perovskite seeds have been introduced during the process by means of colloidal suspensions in acetylacetone. The seeding effects have been evidenced from DTA and XRD measurements, the formation temperature of pure perovskite phase being lowered by 50°C with 5 wt% seeds. More dense powder microstructure is observed in presence of seeds. Work performed within the Concerted European Action on Sol-Gel Processing for Advanced Industrial Material Technologies, Contract No. BRE2, CT92.0137.