Fused filament fabrication of PVDF films for piezoelectric sensing and energy harvesting applications

Fused filament fabrication (FFF) of piezoelectric polymer polyvinylidene fluoride (PVDF) provides a simple manufacturing technique for the fabrication of lead-free piezoelectric devices compared to the traditional manufacturing methods, such as large-scale film extrusion and solution casting. Here, we investigate the effects of the stretching and poling parameters on the enhancement of piezoelectric performance of the printed PVDF films. The stretched and polarized PVDF films with dimensions of 40 × 20 × 0.06 mm (length × width × thickness) possess a piezoelectric charge coefficient (d33) of 7.29 pC N−1 and a fraction of β phase (Fβ) of 65% at a stretching ratio (R) of 4 after being polarized under an electric field of 30 V μm−1. The resulting d33 of the fabricated PVDF films has been substantially enhanced by ∼10–100 times higher than the related reported values of the FFF printed PVDF films. The fabricated PVDF films are capable of detecting compression (d33) and vibration (d31). By blowing four piezoelectric films connected in parallel for 3 min, the energy stored in the capacitor can make a LED blink. Our fabricated piezoelectric PVDF films could be used in the field of pressure sensing, vibration sensing and energy harvesting applications.