Large-scale fabrication and performance improvement of polyvinylidene fluoride piezoelectric composite films

Sensing applications such as wearable electronics, electronic skin, and soft robotics using flexible piezoelectric films have received extensive attention. In this study, we fabricate large-scale 0-3 type composite films of pol-yvinylidene fluoride (PVDF)-doped modified lead zirconate titanate (PZT) particles (PZT@UP) through an extrusion-casting process to enhance piezoelectric properties and explain the piezoelectric performance mech-anism. The introduction of PZT@UP particles improved the dielectric permittivity of the composite films and promoted the polarization of PVDF, which positively affected the piezoelectric properties of PVDF/PZT@UP films. The composite film with 25 wt% PZT@UP possessed an excellent piezoelectric coefficient (d33) of 29 pC/N, which was 93% higher than that of neat PVDF (15 pC/N). Moreover, the addition of PZT@UP particles effec-tively inhibited the movement of PVDF molecular chains and improved the mechanical modulus stability of the composite films. The law of electrostrictive effect of the PVDF/PZT@UP composite films is clarified from the aspects of the movement of PVDF molecular chains, the principle of electric field distribution, and the con-struction of the internal electric field. Further, the similarities and differences between the piezoelectric and electrostrictive mechanisms of the PVDF/PZT@UP composite films are summarized. The extrusion-casting process combined with modified fillers shows promising potential in improving wear and tear of and elec-tricity generation from PVDF-based composite films, leading to a profound impact on the development of large-scale fabrication of piezoelectric sensors.

Automated summary

In this study, large-scale PVDF/PZT@UP composite films were fabricated through an extrusion-casting process to enhance piezoelectric properties. The introduction of PZT@UP particles improved the dielectric permittivity and polarization of PVDF, resulting in improved piezoelectric properties. The addition of PZT@UP particles also improved the mechanical modulus stability of the composite films. The extrusion-casting process combined with modified fillers shows promising potential in improving wear and tear and electricity generation of PVDF-based composite films.