Structure, dielectric and electrocaloric properties of (Ba_0.87Ca_0.13(Ti_0.9Zr_0.1)_{1 − x} (Zn_1/3Nb_2/3)_xO₃ ferroelectric ceramics

The impact of Zn and Nb replacements on the dielectric, ferroelectric, and electrocaloric (EC) characteristics of BCZT−x%ZN ceramics was thoroughly studied. The introduction of Zn and Nb into BCZT−x%ZN not only enhances the dielectric permittivity but also reduces the curie temperature. By employing P–E hysteresis loops across a broad temperature range and applying externally induced electric fields, we investigated the EC temperature change (ΔT) using the Maxwell relation. The EC effect response was determined versus temperature for all BCZT−x%ZN ceramic compositions, ranging from x = 0 to 2%, through ferroelectric polarization and pyroelectric measurements. BCZT−0.5%ZN showed a maximum EC temperature change of ∆T = 0.701 K at 3 kV/mm, with a matching EC responsivity (ξ = ΔT/ΔE) of 0.233 K mm/kV. This discovery underscores the highly promising nature of this material family for electrocaloric applications in proximity to ambient temperatures.