Materials with electrocaloric effect (ECE) and/or thermal switching ratio λ are desirable for developing various heat management devices, but developing high-performance candidates, especially those that simultaneously possess large near room-temperature ECE and λ is actually absent. The Zr-rich PbZr1−xTixO3 (PZT) displays a composition-induced antiferroelectric-ferroelectric (AFE-FE) phase boundary, where an unusual negative ECE is expected. Meanwhile, the electric field-sensitive dipole orientation during the AFE-FE phase transition can be employed to modulate λ. In this work, the Zr-rich PZT with coexisting AFE and FE phases was developed and the AFE-FE phase transition temperature is tuned toward room temperature by changing the Ti content to achieve large negative ECE and λ. A large adiabatic temperature change ΔT of −3.3 K accompanied by a giant λ of 1.84 near 60 °C is captured in optimal PbZr0.95Ti0.05O3 ceramics, demonstrating a prominent application prospect in solid-state refrigeration.

中文翻译：

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接近室温的大负电热效应在富锆钛酸铅中伴有巨大的热开关比


具有电热效应 （ECE） 和/或热开关比 λ 的材料是开发各种热管理器件的理想选择，但实际上不存在开发高性能候选材料，尤其是那些同时具有较大的接近室温 ECE 和 λ 的材料。富含 Zr 的 PbZr1−xTixO3 （PZT） 显示出成分诱导的反铁电-铁电 （AFE-FE） 相边界，预计会出现不寻常的负 ECE。同时，AFE-FE 相变期间的电场敏感偶极子方向可用于调制 λ。在这项工作中，开发了 AFE 和 FE 相共存的富 Zr PZT，并通过改变 Ti 含量将 AFE-FE 相变温度调节到室温，以实现较大的负 ECE 和 λ。在最优 PbZr0.95Ti0.05O3 陶瓷中捕获了 −3.3 K 的大绝热温度变化 ΔT 和 60 °C 附近 1.84 的巨大 λ，在固态制冷中显示出突出的应用前景。