Direct writing polyvinylidene difluoride thin films by intercalation of nano-ZnO

Polyvinylidene fluoride (PVDF) is a preeminent pyrolytic and piezoelectric polymer. It has been widely studied as an ideal material for wearable flexible sensors or low-power electronic equipment. PVDF/ZnO thin films were prepared by direct writing method, which promoted the ordered arrangement of PVDF molecular chains under the action of electric field and thus improved the crystallinity of the beta phase. Meanwhile, the effects of intercalation of ZnO nanoparticles on the crystallinity of PVDF thin films were explored. The results show that appropriate addition of nano-ZnO as nucleating agent can induce the crystallinity of the PVDF film obviously. While the additive amount of nanoparticles was 0.02 wt%, the relative beta phase content of the PVDF film can reach 88.92%. Under the double action of adding ZnO nanoparticles and electric field assistance, the dielectric constant of the composite film increases from 6.9 (pure PVDF) to 12.4 (0.03 wt% ZnO) at a frequency of 1 kHz. The d(33) value of the film without polarization is up to -9.1 pC/N, the output voltage is increased to 351 mV, and the conductivity of the composite film has been improved.

Automated summary

PVDF/ZnO thin films were prepared using a direct writing method, with the addition of nano-ZnO significantly improving the crystallinity and beta phase content of the PVDF film. Additionally, the dielectric constant of the composite film was greatly increased and the conductivity improved through the combined action of adding ZnO nanoparticles and electric field assistance.