Conventionally Prepared Submicrometer Lead-Based Perovskite Powders by Reactive Calcination

Submicrometer powders of various Pb-based perovskites, including PbTiO₃, PbZrO₃, Pb(Zr_0.53Ti_0.47)O₃, and Pb(Mg_1/3Nb_2/3)O₃ were prepared by a reactive calcination process. Using only reagent-grade raw materials and conventional processing techniques, highly reactive powders were produced by reacting the materials near the temperature of maximum volumetric expansion. At this point, the morphological development results in a skeletal-type structure consisting of ultrafine particulates that can be readily broken down further by milling. Powder sizes less than 0.3 μm and as small as 70 nm generally only achievable using chemical processing techniques were achieved. The highly reactive powders allowed densification to occur at temperatures as low as ∼900°C with correspondingly small grain sizes. A model describing the physiochemical behavior and associated morphological development of Pb-based perovskites was herein proposed.