Modelling hysteresis loop properties of ordered and disordered porous BaTiO3 under stress

To understand the hysteresis behavior of porous ferroelectric BaTiO 3 under mechanical stress, a phase-field model is employed to investigate systems with both ordered and disordered pore distributions. The effects of stress applied perpendicular to the electric field direction on ferroelectric domains and corresponding hysteresis loops were systematically explored. We observe that tensile or compressive stress induces linear-shaped hysteresis loops. The shape of the hysteresis loop and the saturation polarization are strongly influenced by pore size and geometry. Increasing pore geometrical disorder (from 0.024 to 0.1432) leads to loop broadening and a shift in coercive field. Notably, clustered pores lead to domain structures and hysteresis responses resembling those of a single large pore. Crucially, this stress-induced linearity enhances the recoverable energy density by 10–20 times compared to the unstressed case, highlighting the potential of porous BaTiO 3 for lightweight energy storage and harvesting applications. Furthermore, disordered pore clusters effectively mitigate strain concentration near high-curvature edges. Quantitative agreement between simulated and experimentally measured hysteresis loops validates our approach, and additionally, a combination of theory and experiment was used to determine the magnitude of pore disorder. These findings provide actionable insights for optimizing porous ferroelectrics through tailored pore architecture and external stress tuning.