1. Schematic of polarization switching, temperature change and entropy change during cooling cycle of electrocaloric effect
2. Feasible combination of positive and negative electrocaloric effect
[10] 3. Direct measurements of electrocaloric effect
4. Electric domain and representative hysteresis loop of antiferroelectrics, schematic of a possible mechanism of negative electrocaloric effect in antiferroelectrics
[27] 5. Negative electrocaloric effect in PbZrO3-based antiferroelectric thin films
6. Interface-defect-enhanced negative electrocaloric effect in PbZrO
3 thin films
[29] 7. Negative electrocaloric effects of PbZrO3, (Pb0.97,La0.02)(Zr0.95,Ti0.05)O3 and B-site nonstoichiometric (Pb0.97,La0.02)(Zr0.95,Ti0.05)1+yO3 (y=-0.03, -0.01, 0.01, 0.03) ceramics under different electric fields
8. Hysteresis loops of PNZST13/2/2 and PNZST43/8/2 under different temperatures,
P-T curves, temperature change Δ
T and entropy change Δ
S of PNZST13/2/2 and PNZST43/8/2
[37] 9. Electrocaloric effect of (Pb0.97La0.02)(Zr0.66Sn0.23Ti0.11)O3 single crystal, (Pb0.97La0.02)(Zr0.66Sn0.27Ti0.07)O3 single crystal, (Pb0.97La0.02)(Zr0.80Sn0.14Ti0.06)O3 ceramics, and (Pb0.97La0.02)(ZrxSn0.94-xTi0.06)O3 ceramics