AC Electrical Conductivity and Dielectric Properties of Perovskite (Pb, Ca)TiO3 Ceramic

Pb1-xCaxTiO3 perovskite crystalline structure with x = 0, 0.2, 0.6, 0.7, and 0.8 were prepared by mixture method. The ac conductivity and dielectric properties of the studied bulk compositions have been investigated in the frequency range 1 x 10(3)-5 x 10(6) Hz and temperature range 303-473 K. The experimental results indicate that the ac conductivity sigma(ac)(omega), dielectric constant epsilon' and dielectric loss epsilon '' depend on the temperature and frequency. The ac conductivity was found to obey the power law omega(s) with the frequency exponent S > 1 decreasing with increasing temperature. The present results are compared to the principal theories that describe the universal dielectric response behavior. Values of dielectric constant epsilon' and dielectric loss epsilon '' were found to be temperature and frequency dependent and the maximum barrier height W-m is calculated.