High Performance Flexible Piezocomposites Based on a Particle Alignment Strategy

Piezocomposites composed of piezoelectric inorganic particles dispersed in a flexible polymer have emerged as promising materials for flexible energy harvesters and sensors. In this work, to overcome the inefficient stress transfer capability in flexible piezocomposites for energy harvester, KNbO 3 (KN) particles prepared by conventional solid oxide process were aligned to form chain‐distributed particles in polydimethylsiloxane (PDMS) matrix by dielectrophoresis. The composite with 8 vol.‐% KN has peak open circuit voltage of 6.3 V and short‐circuit current of 0.82 µA under an applied force of 7 N, which are significantly improved in compared with the sample with piezoelectric particles randomly dispersed. Hugely enhanced stress‐transfer capability of the aligned composite plays a key role in achieving large piezoelectric response. This work provides a promising material candidate for high performance flexible energy harvester.