Enhanced Piezoelectric Coefficient of PVDF-TrFE Films via In Situ Polarization

The d 33 coefficient = 28 pC/N of PVDF-TrFE piezoelectric films was achieved by the in situ polarization. Compared with traditional poling methods, the in situ polarization is performed with low poling voltage and short poling time, and it can ensure the PVDF-TrFE film with enhanced piezoelectric performances and uniform distribution among a large area of 200 mm 2 × 200 mm 2 . The processing influence of drying, annealing, and poling on the crystalline properties and piezoelectric performances were investigated. Besides, the obtained PVDF-TrFE films present a good piezoelectric response to different extents of mechanical stimulations, which have great potential in energy harvesting applications.