Phase transition in Pb5Ge2ZrO11 ceramics

Polycrystalline samples of zirconium-doped lead germanate Pb5Ge2ZrO11 were prepared by a solid-state reaction technique. Preliminary X-ray studies show the formation of the single-phase compound and provided its basic crystal structure. Dielectric constant (ϵ) and loss (tan δ) were measured as a function of temperature (room temperature to 280°C) at different frequencies. Dielectric anomaly and ferroelectric phase transition observed at 160°C was supported by our polarization studies. The activation energy of the sample was calculated from the dielectric data.