Mobility determinations from weight measurements in solid solutions of (Ba, Sr) TiO3

Abstract

Ba1–xSrxTiO3 ceramics and SrTiO3 single crystals subjected to reducing treatment show‐weight losses due to the release of oxygen. In parallel the reduction causes an electrical conductivity which is proportional to the weight loss. On the justified assumption that oxygen vacancies occur during the reduction process and that each vacancy loses an electron to the conduction band at room temperature, it is possible to determine from the weight‐loss measurements the number of electrons and, in combination with the electrical conductivity, their mobility. The mobility thus determined is 0.6 cm2/Vs for BaTiO3, rising with increasing Sr concentration to 5.9 cm2/Vs for SrTiO3. These gravimetrically determined mobilities are in satisfactory agreement with those found from Hall‐effect and thermo‐electric power measurements. Copyright © 1972 WILEY‐VCH Verlag GmbH & Co. KGaA