Giant Negative Electrocaloric Effect in (Pb,La)(Zr,Sn,Ti)O3 Antiferroelectrics Near Room Temperature

(Pb0.97La0.02)(ZrxSn0.94–xTi0.06)O3 (PLZST) antiferroelectric ceramics with x = 0.75–0.90 have been fabricated and found to be a novel electrocaloric material system with a giant negative electrocaloric effect (ΔT = −11.5 K) and a large electrocaloric strength (|ΔT/ΔE| = 0.105 K cm kV–1) near room temperature. Additionally, the PLZST antiferroelectric ceramic also exhibits a large positive electrocaloric effect around the Curie temperature. The giant negative effect and the coexistence of both positive and negative electrocaloric effects in one material indicate a promising possibility to develop mid- to large-scale solid-state cooling devices with high efficiency.