A microcube-based hybrid piezocomposite as a flexible energy generator

Harvesting energy from surrounding mechanical sources to power low-power portable electronics has attracted worldwide attention during the last decade. Herein, we present a high-performance piezoelectric energy generator (PEG) based on lead zirconate titanate (PbZr_0.52Ti_0.48O₃, PZT) microcubes and poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE)). The PZT microcubes with tetragonal perovskite phase were prepared by one-step hydrothermal method. It is demonstrated that cube-shaped piezoelectric particles are advantageous over traditional spherical particles because external force can be readily concentrated on the edges of cubes to generate higher piezoelectric potential. Moreover, different from most of the previous flexible piezoelectric generators, the utilization of high elastic modulus, piezoelectric-active matrix P(VDF-TrFE) in our piezocomposites benefits power generations. The composite with a metal-insulator-metal (MIM) structure produces an open-circuit voltage up to ∼16 V under bending motions. A maximum instantaneous power density of ∼50 μW cm^-3 has been obtained at a load resistance of 160 MΩ. This work provides a facile approach to enhanced piezoelectric response in flexible composites via tailoring the geometry of ceramic fillers.