A giant electrocaloric effect in nanoscale antiferroelectric and ferroelectric phases coexisting in a relaxor Pb0.8Ba0.2ZrO3 thin film at room temperature

Recently large electrocaloric effects (ΔT = 12 K and ΔS = 8 JK-1kg-1 at 776 kV/cm) in antiferroelectric sol-gel PbZr0.95Ti0.05O3 thin film and (ΔT = 12.6 K and ΔS = 60 JK-1kg-1 at 2090 kV/cm) in ferroelectric polymer P(VDF-TrFE)55/45 thin film have been observed near their ferroelectric Curie temperatures 495 K and 353 K, respectively. Here the authors demonstrate a giant EC effect (ΔT = 45.3 K and ΔS = 46.9 JK-1kg-1 at 598 kV/cm) in the nano-scaled antiferroelectric and ferroelectric phases coexisted relaxor Pb0.8Ba0.2ZrO3 (PBZ) thin film at the room temperature 290 K rather than at its Curie temperature 408 K. Field-induced antiferroelectric to ferroelectric phase transition played a crucial role in the dramatic EC property of PBZ thin film.. The giant EC effect of PBZ thin film makes it an attractive material for applications in cooling systems near room temperature.