3D printed ferroelectret with giant piezoelectric coefficient

A ferroelectret cellular structure of poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)] is fabricated by a 3D printing technique that exhibits a giant piezoelectric coefficient of 1200 pC/N, which is 40 times higher than its commonly known film counterpart. It attributes that the bi-polar charge separation in cellular voids upon the corona discharge behaves as macroscopic dipoles. An increase in the surface potential and dielectric constant (from 10 to 20 at 1 kHz) also attributes to charged voids. Furthermore, the deviation of ferroelectric behavior, for instance, the continuous increasing trend in dielectric constant and remanent polarization as a function of temperature attributes to ferroelectret behavior of a 3D printed P(VDF-TrFE) specimen. The mechanical energy harvester (MEH) made with this ferroelectret structure shows prompt response with ∼4 W/m2 of the power density. Furthermore, the benefit of the giant piezoelectric coefficient of the MEH is used to demonstrate self-powered tactile mapping.