Porous, multi-layered piezoelectric composites based on highly oriented PZT/PVDF electrospinning fibers for high-performance piezoelectric nanogenerators

Piezoelectric nanogenerators(PENGs)that can harvest mechanical energy from ambient environment have broad prospects for multi-functional applications.Here,multi-layered piezoelectric composites with a porous structure based on highly oriented Pb(Zr_(0.52)Ti_(0.48))O_(3)/PVDF(PZT/PVDF)electrospinning fibers are prepared via a laminating method to construct high-performance PENGs.PZT particles as piezoelectric reinforcing phases are embedded in PVDF fibers and facilitate the formation of polarβphase in PVDF.The multi-layered,porous structure effectively promotes the overall polarization and surface bound charge density,resulting in a highly efficient electromechanical conversion.The PENG based on 10 wt%PZT/PVDF composite fibers with a 220µm film thickness outputs an optimal voltage of 62.0 V and a power of 136.9μW,which are 3.4 and 6.5 times those of 10 wt%PZT/PVDF casting film-based PENG,respectively.Importantly,the PENG shows a high sensitivity of 12.4 V·N^(−1),presenting a significant advantage in comparison to PENGs with other porous structures.In addition,the composites show excellent flexibility with a Young’s modulus of 227.2 MPa and an elongation of 262.3%.This study shows a great potential application of piezoelectric fiber composites in flexible energy harvesting devices.