Ionic conductivity of undoped BaTiO3−δ with electron transfer suppressed

It is indicated that association (with an association enthalpy of 0.25 eV) occurs between carrier oxygen vacancies and the charge compensating acceptor species, whether extrinsic or intrinsic, at temperatures below 1073 K. The higher temperature result is in good agreement with those obtained indirectly from the identical quality specimens. The chemical diffusivity has been determined from the temporal change of the cell voltage under a galvanostatic condition and is also in satisfactory agreement with the earlier study.