Studies on the structural dielectric electrical and thermoelectric properties of some complex perovskite oxides

Abstract

The thesis presents an investigation of dielectric electric and newlinethermoelectric properties of some rare earth substituted barium and strontium newlinebased complex perovskites The synthesis of the compositions is carried out newlineusing high temperature solid state reaction technique Calcination temperature newlineand duration of calcination are suitably varied to obtain single phase newlinematerials Structural characterization is carried out using powder Xray newlinediffraction and the microstructural studies using SEM All the samples are newlinefound to have double cubic perovskite structure newlineThe dielectric constant of all the samples are high40 from newline100 Hz to 5MHz and over a temperature range of 300K to 700K The newlinedielectric properties are thermally stable The dielectric loss tan is low at newlinehigh frequencies and at high temperatures newline newline