The densification behavior of flash sintered BaTiO₃

Herein, we report the densification behavior of a typical electric ceramic, barium titanate (BaTiO₃), and highlight the role of oxygen vacancies in rapid densification of BaTiO₃ during flash sintering. The activation energies of flash- and conventional-densification processes are compared to reveal that the initiation of flash sintering is triggered by the accumulation of generated oxygen vacancies under the electric field. Furthermore, the densification kinetics of BaTiO₃ and X-ray photoelectron spectroscopy of flash-sintered BaTiO₃ infer that the ultrafast densification during the flash-sintering stage is dominated by the migration of electric field-generated defects coupled with defect-annihilation by take-in oxygen from the environment.