High-Performance Hybrid Triboelectric Generators Based on an Inversely Polarized Ultrahigh β-Phase PVDF

Triboelectric nanogenerators (TENGs) have been recognized as a key potential solution for powering microdevices by converting mechanical energy and interfacial friction to electricity. The TENG device performance can be enhanced by the incorporation of ferroelectric materials, either ferroelectric polymers or ceramic particles, at the contact interface. Contact between ferroelectric components at the TENG contact interface leads to an increased electrostatic induction from the piezoelectric dipoles. If the ferroelectric polarization between adjacent contact surfaces is inversely polarized, an even greater enhancement in mechanical-to-electrical energy conversion can be observed. Here, we are reporting a TENG device based on such inversely polarized ferroelectric contact interfaces. An ultrahigh beta-phase content (88%) poly(vinylidene fluoride) (beta-PVDF) is produced by the folding and pressing method followed by electrical poling in opposing directions. A 5 cm(2) inversely polarized beta-PVDF TENG was demonstrated to generate an open-circuit voltage of 1350 V and a short-circuit current of 0.5 mA upon contact separation. A maximum power of 24 W m(-2) can be achieved, which is among the highest outputs among PVDF-based TENGs reported to date.