Distinguishing intrinsic and interfacial pyroelectric effects by polarization reversal measurements

Pyroelectric devices hold promise for thermal energy harvesting and sensing. While previous studies have focused on the intrinsic pyroelectric response, they neglect the interfacial pyroelectric effect at the electrode-material interface, leading to an overestimation of the intrinsic contribution to pyroelectricity. By leveraging the reversibility of the intrinsic effect and the irreversibility of the interfacial effect, we propose a method that uses polarization reversal measurements to distinguish between them. By calculating the contributions of the two effects for different ferroelectric films, it is observed that the intrinsic and interfacial pyroelectric effects dominate in PbTiO3 and BaTiO3 films with Schottky contacts, respectively, modifying the energy Figure of Merit. Furthermore, a machine learning model is employed to predict the proportion of intrinsic and interfacial effects, offering strategies for material screening. This work provides a rapid optimization approach and guidelines for high-performance pyroelectric devices based on ferroelectric films. The authors develop a polarization reversal method to distinguish intrinsic and interfacial pyroelectric effects in ferroelectric films and clarify their material-specific dominance. It enables the development of better thermal energy harvesters and sensors.