PST thin films for electrocaloric coolers

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 degrees C to -6.9 degrees C over a broad range of operating temperatures near room temperature (1-127 degrees 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.