隨著物聯網科技的蓬勃發展，使得電力自我供應的無線感測器需求大增，而摩擦奈米發電裝置可將環境中微小的動能轉變為電能，對於供應電力給予無電網支援的無線感測器極具發展潛力。本研究針對固液接觸的摩擦發電裝置進行改良，採用旋轉塗佈法將單一材料或複合材料分別塗佈於ITO玻璃表面，以探討不同薄膜材料的摩擦發電的效果。當使用單一非晶氟系材料、PTFE懸浮液複合材料與蠶絲蛋白複合材料薄膜進行電潤濕電荷注入時皆能使薄膜材料表面電荷密度增加並提高輸出電流，其中非晶氟系材料與蠶絲蛋白複合材料皆能提高電流約12倍，並且蠶絲蛋白複合材料因為其強氫鍵的相互作用，能使薄膜表面缺損減少而提高薄膜的穩定性，而PTFE懸浮液複合材料因為能抓住更多注入電荷而擁有較高的表面電荷密度，能提高約25倍以上的輸出電流。最後，本研究也針對薄膜厚度、溶液濃度與液滴摩擦發電裝置放置角度對於輸出電流的影響進行探討，當薄膜厚度愈薄，電潤濕電荷注入時，可使薄膜材料擁有的表面電荷密度愈高，使得摩擦發電的輸出電流值愈大；摩擦發電裝置放置角度改變時，主要影響電流產生之持續時間；而當溶液濃度提高，電導度提升因此也使電流輸出提高。本研究藉由複合薄膜材料與薄膜厚度的控制，提高了固液接觸摩擦發電裝置之電荷注入的效果，提高薄膜材料表面電荷密度而大幅地提升液滴摩擦發電裝置的電流輸出，有助於未來液滴摩擦發電裝置的發展。

In this study, the mechanism of a solid-liquid triboelectric nanogenerator is investigated using the dual-electrode mode for harvesting hydropower, and the electrowetting-assisted charge injection method was used to improve the current output. To increase the amount of charge captured by the film after the charge injection, a film material was selected based on the contact electrification property to increase the surface charge density of the film and improve the current output of the electricity generator. The results showed that the output current of fluoropolymer film can be increased by more than 25 times after an electrowetting-assisted charge injection by adding PTFE particles; the surface defects of the film can be reduced, and the current stability can be improved by adding silk powder. It was also proved experimentally that a thinner film induces a higher current after the electrowetting-assisted charge injection, and a higher concentration (conductivity) of droplet solution leads to a higher current output. The equivalent circuit and experimental results show that the platform angle does not affect the value of the current output. The results of this study provide a better understanding of the power generation mode and mechanism of a droplet electricity generator and indicate the feasibility of the generator to improve the current output and surface by using different doped materials.

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