Kinetics controlled aging effect of ferroelectricity in Al-doped and Ga-doped BaTiO3

Abstract

Our experiments on ferroelectric aging of Al3+- and Ga3+-doped BaTiO3 ceramics reveal the crucial role of migration kinetics of point defects (oxygen vacancies) besides the thermodynamic driving force based on the symmetry conforming short-range ordering scenario. The doping with Ga3+ or tiny Al3+ ions shows the clear aging effect, while the high-level Al3+-doping suppresses the aging effect. The suppression is mainly attributed to the kinetically limited migration of oxygen vacancies due to the lattice shrinkage, while the other mechanisms may also make sense.