Biocompatible, flexible, and compliant energy harvesters based on piezoelectric thin films

Piezoelectric energy harvesters are promising transducers for supplying low-power mobile/portable electronics, wearable and implantable devices, or for autonomous wireless sensors and microsystems, which are of increasing importance for monitoring environmental and structural health, sensing in automotive applications, human health and wellness. One of the main requirements for such applications is the ability to develop piezoelectric materials and devices generating enough voltage/power even from tiny mechanical or biomechanical excitations at extremely low frequencies and out-of-resonance. In addition to high performance, wearable devices and medical implants require biocompatibility of materials/devices in the long term. This paper reviews recent advances on biocompatible, flexible, and compliant energy harvesters based on piezoelectric thin films scavenging energy from (bio)mechanical movements or flows induced deformations.