Structural order differentiation unlocks the energy storage performance of commensurate antiferroelectric ceramics
摘要
Commensurate modulated antiferroelectric ceramics exhibit limited application prospects, a quasi transient antiferroelectric-ferroelectric phase transition has locked their energy storage performance. Highly homogeneous oxygen octahedra set produce only one type of antiferrodistortion-ferrodistortion transition, followed by a rapid triggering of the antiferroelectric-ferroelectric phase transition. Here, we propose a strategy of structural order differentiation engineering to disrupt the homogeneity of oxygen octahedra by initiator/enhancer co-substitution, and we have successfully unlocked the energy storage performance of commensurate modulated antiferroelectric ceramics. By constructing oxygen octahedra sets with highly differentiated rotational distortions, an energy storage density of 23.11 J/cm3, an energy storage efficiency of 85.55%, and a discharge energy density of up to 16.45 J/cm3 are simultaneously achieved, which is superior to other antiferroelectric ceramics and dielectric ceramics. By limiting the doping window, the commensurate modulation characteristics of polarization order can be maintained, which ensures the maximum polarization. A highly differentiated octahedra rotational distortion yields a multi-stage antiferrodistortion-ferrodistortion transition and a coexistence of polymorphic ferroelectric phases, significantly prolonging the polarization process. The proposed structural order differentiation shows guiding significance for the development of antiferroelectric, and the obtained energy storage performance promotes the practical applications of antiferroelectric ceramic capacitors.