Thickness dependence of electrocaloric effect in high-temperature sintered Ba0.8Sr0.2TiO3 ceramics

This paper demonstrated the thickness dependence of electrocaloric effect (ECE) in Ba0.8Sr0.2TiO3 ferroelectric ceramics. The high-temperature sintered sample has inhomogeneous properties along the thickness direction although the microstructure has uniform features throughout. The core zone exhibits a much lower resistivity than that of the whole sample because of more ions' valence variation. Under a same electric field of 30 kV/cm, the ECE ΔT drops from 1.35 K to 1.12 K by reducing the thickness step by step. But the thinnest core sample can sustain much higher electric fields (>50 kV/cm) and exhibits a larger ΔT of 1.67 K, i.e. it has a high ECE value despite a low ECE strength.