Perovskite stabilization in Fe- and Mg-doped Pb(Zn1/2W1/2)O3 and their dielectric characteristics

Stabilization of a perovskite structure by solid-state reaction in as-yet unreported Pb(Zn1/2W1/2)O3 ceramics was attempted with compositional modification. A wide range of fractions of Pb(Fe2/3W1/3)O3 were initially introduced into the host material, and 20 mol% Pb(Mg1/2W1/2)O3 was subsequently added to the resulting composition in order to enhance perovskite formation. The perovskite development yield of 62.5% (without any fraction of Pb(Fe2/3W1/3)O3 introduced) increased with Pb(Fe2/3W1/3)O3 contents and finally reached 99.9%. The lattice parameters of the perovskite structure in the cubic symmetry range decreased steadily from 0.4002 to 0.3979 nm with increasing Pb(Fe2/3W1/3)O3. The relative permittivity values of the ceramics increased from 72 to 4910 (1 MHz) with increasing Pb(Fe2/3W1/3)O3. By contrast, the dielectric maximum temperatures in the cubic perovskite range changed only slightly from -111 to −124 °C (1 MHz), quite insensitive to the compositional modification. Meanwhile, the phase transition changed gradually from sharp to diffuse modes with the Pb(Fe2/3W1/3)O3 substitution.