Abstract:
To address the difficulty of high integration, flexibility and low power density caused by the traditional nanogenerators with alternating current (AC) output and still need to use external rectifiers for direct current (DC) conversion, in this paper, poly(vinylidene fluoride) (PVDF) electrostatically spun film was used as a substrate and polypyrrole (PPy) was gas-phase polymerized on the surface of the film to produce a composite nanofibrous film of PVDF/PPy, and based on the Schottky collation principle, a DC nanogenerator was constructed by this composite nanofibrous film. The composite nanofiber membrane was used to construct a DC nano-generator based on Schottky finishing principle. The effects of oxidant concentration on the morphology of PVDF/PPy composite nanofiber membrane and the electromechanical performance of DC nano-generator were investigated under different polymerization time. The results show that when the oxidant concentration is 2 mol/L and the polymerization time is 90 min, the electrical output performance is optimal, corresponding to a peak voltage output of 1.23 V, a peak current output of 210.55 μA, and a theoretical power density of 28.77 μW/cm
2. In this study, this PVDF/PPy DC nano-generator was demonstrated, and the energy conversion mechanism originates from the piezoelectric effect of piezoelectric polymer and the rectification effect of Schottky junction. These DC nano-generators are flexible, integrated and self-rectifying, and can be flexibly used in various places to provide power directly to electronic devices.