Giant electrocaloric effect in BaZr0.2Ti0.8O3 thick film

Abstract

We report the giant electrocaloric effect (ECE) of BaZr0.2Ti0.8O3 (BZT) thick film near room temperature. The BZT thick film was fabricated by the tape casting method with the thickness of 12.0 μm. Due to the near invariant critical point composition, relaxor behavior, and the stress generated between the film and the substrate, the thick film exhibits a large adiabatic temperature drop ΔT = −7 °C under 19.5 MV/m electric field, large EC coefficient ΔT/ΔE = 0.50 × 10−6 K · m · V−1, ΔS/ΔE = 0.88 × 10−6 J · m · kg−1 · K−1 · V−1 over a wide temperature range near room temperature, where ΔS is the isothermal entropy change and ΔE is the applied field. These high EC properties and possibility of fabrication of the EC ceramics into multilayer ceramic capacitor configuration provide solution for the application of the EC material for practical cooling device applications.