Effects of oxygen vacancies and grain sizes on the dielectric response of BaTiO3

摘要

The effects of grain size and oxygen vacancies on the dielectric responses of BaTiO3 ceramics wereninvestigated using wideband dielectric spectroscopy. Both dipole and ionic polarizations werenenhanced by the reduction in grain size down to 2.5 u0002m. The annealing in low oxygen partialnpressure markedly suppressed the dipole polarization possibly due to the domain-wall clamping bynoxygen vacancies. To explain the dielectric response of BaTiO3 ceramics, a complex structurenincluding gradient lattice strain layers u0002GLSLu0003 were proposed as a model of 90° domain structure.