The stability of the electrocaloric effect under electric field cycling is an important consideration in the development of solid-state cooling devices. Here we report measurements carried out on Ba(Zr_0.2Ti_0.8)O₃ ceramics which reveal that the adiabatic temperature change, polarization-electric field hysteresis loops and dielectric permittivity/loss show stable behavior up to 10⁵ cycles. We further demonstrate that the loss in electrocaloric response observed after 10⁵ cycles is associated with the migration of oxygen vacancies. As a result, the electrical properties of the material are changed leading to an increase in leakage current and Joule heating. Reversing the polarity of the electric field after every 10⁵ cycles changes the migration direction of oxygen vacancies, thereby preventing charge accumulation at grain boundaries and electrodes. By doing so, the electrocaloric stability is improved and the adiabatic temperature remains constant even after 10⁶ cycles, much higher than achieved in commercially available barium titanate ceramics.

电场循环下电热效应的稳定性是固态冷却装置开发中的重要考虑因素。在这里，我们报告了在Ba（Zr _0.2 Ti _0.8）O ₃陶瓷上进行的测量，结果表明，绝热温度变化，极化电场磁滞回线和介电常数/损耗显示出高达10 ⁵个循环的稳定行为。我们进一步证明，10 ⁵后观察到的电热反应损失周期与氧空位的迁移有关。结果，材料的电性能改变，导致漏电流和焦耳热的增加。每10 ⁵个循环后反转电场的极性会更改氧空位的迁移方向，从而防止电荷在晶界和电极上积累。通过这样做，即使在10 ⁶个循环之后，电热稳定性也得到改善，并且绝热温度保持恒定，这远高于市售钛酸钡陶瓷所达到的绝热温度。