Electric and Dielectric Bahaviour of PbZr_0.6 Ti_0.4O₃ and PbSr_0.6Ti_0.4O₃ Ceramics

Solid solutions of PbZr_0.6Ti_0.4O₃ and Pb_0.6Sr_0.4TiO₃ were prepared by solid state combustion route. They were characterized by XRD, FTIR Spectroscopy and Raman Spectroscopy. The dielectric properties and the loss tangent of the samples were studied as the function of frequency and temperature. The electric conductivity of the samples was studied as a function of temperature. The XRD and FTIR studies confirmed the formation of monophasic and homogeneous samples. The Raman's Spectroscopy of all the samples showed the presence of soft optical phonons in lower frequency range. The dielectric constant of the samples shows decrease with frequency. The dielectric constant of the samples showed a broad maximum at transition temperature and a peak value of dielectric constant for both the samples showed that it is independent of frequency thereby indicating its non relaxor behaviour. The loss tangent of the sample showed decrease with frequency and increase with temperature. The electrical resistivity of the samples showed decrease with increase in temperature thereby representing their semiconducting behaviour.