Mechanism of aging effect in hybrid-doped BaTiO3 ceramics: electronegativity and ionic radius

Abstract

Physical properties of ferroelectric materials are usually tailored (for high operation temperature, temperature stability, etc.) through introduction of acceptor and donor dopants that usually induce different aging phenomena. Hence it is of great interest to understand the aging behavior in the presence of both acceptors and donors. In this work, we report the aging effect in hybrid-doped BaTiO₃ ceramics, reflected by the time-dependent change of polarization (P)–electric field (E) hysteresis loops in these cases with different dopant combinations of acceptors (Mn³⁺, Fe³⁺, Co³⁺) and donors (Nb⁵⁺, La³⁺). The results indicate that the electronegativity and the ionic radius of acceptors, rather than the substitution site of the donors, play the key role in the formation of defect pairs which dominates the aging effect in hybrid-doped ferroelectrics. Finally, we propose a unified microscopic mechanism for the aging phenomena in hybrid-doped ferroelectrics, and it provides direct instructions for manipulating the aging effect in hybrid-doped ferroelectric materials.