Some dielectric properties of strontium titanate doped with some metal oxides.

ABSTRACT

SrTio3 and SrTiO3 doped with CeO2, Gd2O3 and CuO were prepared according to the recommended procedure using the ceramic method. The doping concentrations ranged from 0.5 to 5 mole% and the prepared materials were structurally investigated by X-ray diffraction and IR absorption spectrum. The dielectric constant and loss were measured within the frequency band 105 to 107 Hz and the temperature range from 20 to 50 degree. The dielectric relaxation proces and its thermodynamic parameters, the activation enthalpy and the entropy changes [delta H epsilon and delta S epsilon] were calculated using the usual rate equations. The results were correlated with the structure of the titanates and the effect of doping was discussed