Phase evolution and dielectric characterization of lead nickel niobate-lead zirconate ceramics prepared from the hydrothermally derived precursors

The perovskite compounds with the composition of (1 - x) Pb(Ni1/3Nb2/3)O-3- xPbZrO(3) have been successfully prepared from hydrothermally treated precu rsors. During calcination, the primary intermediate compound is pyrochlore phase in the Pb(Ni1/3Nb2/3)O-3-TiCh composition, while it is PbZrO3 on the PbZrO3-rich side. On calcination at 800 degrees C, all precursors convert i nto perovskite phases. In the formed solid solutions, increasing PbZrO3 con tent results in a rise in the apparent Curie temperature as well as the max imum dielectric permittivity. The Pb(Ni1/3Nb2/3)O-3-rich perovskites (x < 0 .8) possess the characteristics of relaxer ferroelectrics. With increasing PbZrO3 content, the dielectric response gradually becomes less diffuse and dispersive, reflecting a reduction in the relaxer characteristics of the fo rmed perovskites.