Dielectric relaxation in valence compensated solid solution Sr_0.65La_0.35Ti_0.65Co_0.35O₃

The valence compensated solid solution Sr_0.65 La_0.35 Ti_0.65 Co_0.35 O₃has been found to exhibit dielectric relaxor behaviour with a very high value of the dielectric constant. In the present investigation, this composition has been prepared using different processing parameters and routes, viz (a) solid-state sintering at 1350 °C followed by furnace cooling, (b) sintering at 1350 °C followed by annealing at 1000 °C, (c) sintering the sample prepared by the sol-gel route at 1100 °C and (d) sintering the powder prepared by the solid-state ceramic route at 1350 °C with 1 wt% SiO₂as a sintering aid. The dielectric characteristics were measured in the temperature range 300-500 K and frequency range 0.1 kHz-1 MHz. The dielectric characteristics of this composition are greatly influenced by processing parameters and routes. The dielectric relaxation in these materials was studied using impedance and modulus spectroscopic techniques.