Abstract
Ferroelectric Pb(Fe2/3W1/3)O3 was synthesized by a new two-stage precipitation process. On heating precipitates, PbWO4, pyrochlore phase, and Pb(Fe2/3W1/3)O3 formed as major reactants at 300°, 510°, and 700°C, respectively. A small amount of a liquid phase that accelerated densification was also found at 680°C. A pure compound of Pb(Fe2/3W1/3)O3 formed at 870°C. However, it melted incongruently at 930°C to form Pb2WO5 and facet-shaped magnetic PbFe12O19. The predominant formation mechanism of precipitation-derived Pb(Fe2/3W1/3)O3 is considered to include the formation of pyrochlore phase and its subsequent reaction to form Pb(Fe2/3W1/3)O3. The formation process of Pb(Fe2/3W1/3)O3 in the precipitation method is relatively simple in comparison with the solid-state reaction. This is attributed to the improved homogeneity and reactivity of the starting materials in precipitates.
