隨著智能紡織品的發展以及對可再生能源需求的增加，柔性機械能採集器和傳感應用關鍵材料的開發成為研究重點之一。
聚偏二氟乙烯 (PVDF)擁有優異的壓電性能，且具備高柔韌性、輕巧及生產成本低廉等優點。故本研究將具有壓電特性的聚偏二氟乙烯（PVDF）與不同粒徑之氧化鋅（ZnO）奈米壓電粉體進行複合摻混，再藉由操作簡易且低成本的靜電紡絲技術搭配收集裝置，開發具有高壓電特性之奈米纖維膜並評估其壓電能力，比較氧化鋅（ZnO）粒徑於PVDF奈米纖維膜中對壓縮、拉伸和彎曲下壓電性能之影響。
研究結果顯示，ZnO 奈米粉體摻混增強了PVDF之壓電響應。其中，PVDF@L-ZnO 奈米壓電發電機(PENG)元件可以在動態拉伸下產生 42 mV 和 82 nA、彎曲下 2.8 V 和 323 nA及壓縮下 5.6 V 和 1300 nA 的輸出電壓和電流值。此開發之PVDF@L-ZnO PENG元件可成功驅動4個發光LED二極體及充電於電容器後啟動LCD液晶顯示器。整合之PENG 元件裝置實際應用面，收集環境周圍廢棄振動機械能，如除濕機、空壓機、離心機及冷凍乾燥機等物理振動，借助10μF 電容器成功驅動LCD液晶顯示器於77 秒內。這些結果表示，本團隊開發之PENG元件具備從廢棄的環境振動能量中獲取能量之潛力，使人們能利用日常活動產生之振動能為其電子設備充電。
目前大多數文獻將能量採集器及感測器分開探討，但本研究團隊在後續測試中，以不同測試條件下，如從人類步行及深呼吸的動作中產生 8V 和 0.04 V 的輸出電壓，佐證此開發之PENG 元件能共同於兩者應用中皆有良好表現，建立本篇的獨特性。
此研究顯示，本團隊開發之PENG元件為一突破性能量收集器，用於收集環境機械能以轉換電能，並作為潛在有效的可穿戴式傳感器應用，將於可再生能源和綠色能源利用相關的開發中發揮關鍵作用。

With the development of intelligent textiles and the increase demand for green and renewable energy, the development of key materials for flexible energy storage and sensing applications is the focus of research . Polyvinylidene fluoride (PVDF) is a popular piezoelectric polymer due to its high flexibility, lightweight and cost-effective in production. Therefore, polyvinylidene fluoride (PVDF) with piezoelectric properties was incorporated with zinc oxide (ZnO) ceramic nanoparticles of different particle sizes prepared by electrospinning for fabricating a flexible piezoelectric nanogenerator (PENG).
In this study, electrospun PVDF@ZnO membrane containing ZnO with large particle (PVDF@L-ZnO) and small particle (PVDF@S-ZnO) was prepared by simple solution electrospinning method, and the effect of incorporation of ZnO and its particle size on the piezoelectric property of the PENG was systematically investigated. The piezoelectric property of the fabricated PENG device was evaluated under the different mechanical conditions of tension, compression, and bending.
The results indicate that the incorporation of ZnO nanoparticles enhances the piezoelectric response of the PVDF under all studied conditions. In particular, the PVDF@L-ZnO PENG device can generate electrical output voltage and current of 42 mV and 82 nA under tension, 5.6 V and 1300 nA under compression as well as 2.8 V and 323 nA under bending. Besides, this developed electrical energy was utilized for real applications and the developed PVDF@L-ZnO PENG device can energize 4 LED, turn on LCD and charge different capacitors. Besides, the developed PENG device was utilized for real applications to harvest waste mechanical energy from Air compressor machine of 60 Hz being used for its common purpose and it exhibited that the fabricated L-ZnO@PVDF PENG device can harvest the being wasted mechanical energy and can turn on LCD within 77 s with aid of 10 µF capacitor. The developed PENG device also displayed stable cyclic charging and discharging property that is very important for real applications. Moreover, the PENG device can also generate an output voltage of 8V and 40 mV from the human activity of walking and deep breathing.
In summary, we achieved a higher electrical performance at the the PVDF@L-ZnO PENG device. The realistic utilities of our fabricated piezoelectric generators have been proved by charging capacitor , energize 4 LED and turn on LCD in a short time under repetitive finger impartation.
This study shows that the nanocomposite fiber based PENGs is a promising energy harvester for the harvesting of waste mechanical energy to converting electrical energy and as potentially effective wearable sensor applications. We anticipate that will play a crucial role in solving the problem related to renewable and green energy utilization.

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