Ferroelectrets: Recent developments

Ferroelectrets (also called piezoelectrets) are relatively young members in the family of piezo-, pyro- and ferroelectric materials. They exhibit ferroic behaviour phenomenologically undistinguishable from that traditional ferroelectrics, although materials per se essentially non-polar space-charge electrets with artificial macroscopic dipoles (i.e. internally charged cavities). Since ferroelectrets not only represent a scientific curiosity but also have great application potential, they attracted tremendous attention science industry. The research development has witnessed significant progress past few years. New large transverse piezoelectric activity, biodegradable as well 3-D printed reported. Charging methods high efficiency proposed based on better understanding physico-chemical processes during charging. insights into piezoelectricity provided. ferroelectret-based piezoelectric-magnetic multimodal transducer films opens up new avenues for ferroelectrets. Particularly, more novel applications flexible pressure sensors, health monitoring, energy harvesting, air-coupled ultrasonic non-destructive testing etc. Here, these exciting recent advancements field ferroelectret reviewed discussed.