Studies of the effect of additions of some elements on the electrical conductivity of strontium titanate

ABSTRACT

The AC conductivity as a function of temperature was measured in the temperature range of 298-748K at a frequency of 20 kHz for pure and doped SrTiO3. The plots of log sigma showed that all curves had the same feature in common whatever the type or concentration of dopants. The curves possessed two horizontal plateaux where the values of sigma did not change with temperature. There were three linear parts where the conductivity increased as a function of temperature. The values of activation energy for conduction delta E1, delta E2 and delta E3 were calculated for these parts. A further increase of dopants created imperfections