PST thin films for electrocaloric coolers

Abstract

Relaxor behaviour in a thin film of partially ordered PbSc0.5Ta0.5O3 (PST) was confirmed via slim P–E loops and the frequency dependence of the temperature at which the dielectric constant is maximum. Indirect measurements of the electrocaloric effect suggest that removing a field of 774 kV cm−1 yields a temperature change of −3.5 °C to −6.9 °C over a broad range of operating temperatures near room temperature (1–127 °C), with a correspondingly large refrigerant capacity of 662 J kg−1. In addition to low electrical hysteresis, there is negligible thermal hysteresis. PST thin films are therefore promising for EC cooling near room temperature.