Giant Electrocaloric Effect and Ultrahigh Refrigeration Efficiency in Antiferroelectric Ceramics by Morphotropic Phase Boundary Design

Abstract

= 0-0.08) ceramics and achieves a superior ECE performance. An unprecedented high electrocaloric strength of 1.52 K·mm/kV and an ultrahigh refrigeration efficiency (coefficient of performance = 16) are obtained in PBLZT4, in the MPB near AFE end. Moreover, a large negative ECE, with the highest strength up to -0.41 K·mm/kV, is also realized due to the electric field-induced AFE-FE transition. The coexistence of giant positive and negative ECEs at adjacent temperatures can further improve the cooling capacity (∼17%) of solid-state refrigeration in a well-designed cooling cycle. This work provides a brand new materials design strategy to achieve giant positive and negative ECEs simultaneously and a novel cooling cycle to efficiently utilize the two effects.