Flexibility, higher piezoelectric performance, and long-lasting stability of devices have a great demand in next generation energy technologies. Polyvinylidene fluoride (PVDF) polymer has a greater mechanical flexibility, but it suffers from low piezoelectric performance. Herein, sandwich-structured piezoelectric film (SS-PF) is designed by inserting the conductive poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS) layer between two PVDF layers. The SS-PF based flexible piezoelectric energy harvester (f-PEH) generates higher voltage and current of 3.73 times and 4.64 times than the pristine PVDF film type f-PEH. Moreover, the SS-PF based f-PEH shows no degradation in the output voltage confirming the excellent long-lasting stability over 6 months. DFT simulation shows the occurrence of intermolecular forces between the PVDF/PEDOT:PSS interface. The electric field-dependent charges alignment in PEDOT:PSS may induce the charge accumulation at the PSS-PVDF interface and charge depletion at the PEDOT-PVDF interface leading to the change in orientation of molecular structure in PVDF. Next, the SS-PF based f-PEH is tested for a vibration sensor to monitor the vibrations of curvy pipes and machines, and its output voltages are comparable with the commercial PVDF vibration sensor to confirm the real-time use. The results present a novel design strategy, indicating a new direction for investigating piezo-polymer-based f-PEH.

中文翻译：

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通过在压电聚合物中插入导电层来实现持久、稳定和增强的能量收集


器件的灵活性、更高的压电性能和持久的稳定性在下一代能源技术中有着很高的要求。聚偏二氟乙烯 （PVDF） 聚合物具有更大的机械柔韧性，但压电性能较低。本文通过在两个 PVDF 层之间插入导电聚（3,4-乙烯二氧噻吩）聚苯乙烯磺酸盐 （PEDOT：PSS） 层来设计三明治结构压电薄膜 （SS-PF）。基于 SS-PF 的柔性压电能量收集器 （f-PEH） 产生的电压和电流分别是原始 PVDF 薄膜型 f-PEH 的 3.73 倍和 4.64 倍。此外，基于 SS-PF 的 f-PEH 的输出电压没有下降，证实了 6 个月内出色的持久稳定性。DFT 模拟显示了 PVDF/PEDOT：PSS 界面之间分子间作用力的发生。PEDOT：PSS 中的电场依赖性电荷排列可能诱导 PSS-PVDF 界面的电荷积累和 PEDOT-PVDF 界面的电荷耗尽，从而导致 PVDF 中分子结构方向的变化。接下来，对基于 SS-PF 的 f-PEH 进行振动传感器测试，以监测弯曲管道和机器的振动，其输出电压与商用 PVDF 振动传感器相当，以确认实时使用情况。结果提出了一种新的设计策略，为研究基于压电聚合物的 f-PEH 指明了新的方向。