Giant electrocaloric effect in the thin film relaxor ferroelectric 0.9PbMg1∕3Nb2∕3O3–0.1PbTiO3 near room temperature

The giant electrocaloric effect and high effective cooling power near room temperature for BaTiO3 thick film

“…Under an ultrahigh field of 800 kV/cm, the sample exhibits a giant electrocaloric effect of DT ¼ 7.1 K and DS ¼ 10.1 J/kg Á K at 80 C, 15 which exceeds the ECE value in most ferroelectric ceramics in previous reports. [5][6][7][8][9][10] Although the PbZr 0.95 Ti 0.05 O 3 thin film in Ref. 3 has higher ECE DT of $12 C, its DS of $8 J/kg Á K is smaller due to high operating temperature of 222 C. Because (1) large entropy change is more practical for the refrigerating application, (2) low working temperature would open up wider application prospect, and (3) large effective volume of multilayer thick film produces huger heat absorption capacity, the BaTiO 3 multilayer thick film has more promising application future.…”

“…Since 2006, the giant ECE (DT max > 5 K) was reported successively in various ferroelectric ceramics or polymer films, [3][4][5][6][7][8][9][10][11][12] where the ultrahigh applied field played a key role. Up to now, intense research and development efforts are still on-going and there are many blank, especially on the kinetics problem.…”

Investigation of the electrocaloric effect in a PbMg2/3Nb1/3O3-PbTiO3 relaxor thin film

“…We have previously demonstrated that a giant ECE could be obtained for thin films because it is possible to apply a higher E. 14,16 ⌬T max = 12 K for PZT thin films near T C = 226°C, 14 and ⌬T max = 5 K for 0.9PMN-0.1PT thin films near 60°C, 16 were determined by indirect measurements using Eq. ͑1͒.…”

Effect of domain walls on the electrocaloric properties of Pb(Zr1−x,Tix)O3 thin films

“…1) and 0.9PbMg 1/3 Nb 2/3 O 3 -PbTiO 3 . 2 The electrocaloric effect refers to the change in temperature of a ferroelectric under adiabatic conditions in response to a change in the applied electric field. Since the spontaneous polarization in a ferroelectric is temperature dependent, an electric field that influences ferroelectric ordering can cause a change in temperature by raising or lowering the entropy associated with the order parameter.…”