Asymmetric Electrostrain/Electrobending in Piezoelectric Ceramics: Role of Defect Dipoles or Oxygen Vacancies

-based ceramics, thereby elucidating the origin of poling-direction-independent electrobending in piezoelectric ceramics with volatile elements. These findings mark a milestone in understanding the mechanism underlying giant defect-mediated electro-deformation, settle widely debated controversy about electrobending, and open new avenues for the rational design of advanced piezoelectric ceramics.