PST thin films for electrocaloric coolers

Relaxor behaviour in a thin film of partially ordered PbSc 0.5 Ta 0.5 O 3 (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.