本研究主題是利用電紡絲技術製備具有壓電性質之鈦酸鋇奈米線/高分子奈米複合纖維。首先利用兩段式水熱法合成鈦酸鋇。第一階段是以鐵氟龍密封之不鏽鋼水熱罐製備鈦酸奈米線，主要挑戰是找出適當之反應條件。第二階段則須在維持相同之一維形貌下，將鈦酸轉化為鈦酸鋇奈米線。我們發現只需以90oC加熱一小時即可達成。將獲得之鈦酸鋇奈米線以不同之比例，分散於聚(偏氟乙烯-三氟乙烯)(P(VDF-TrFE))的溶液中，並透過調整DMF/丙酮溶劑之比例，得到不同固含量之電紡前驅溶液。然後改變極化電場強度及前趨溶液流速，以能電紡出不同直徑與形貌的奈米複合纖維。在金屬電極基板上收集到的複合纖維膜，需要做統一規格的裁切，並黏貼上電極，再以PDMS封裝，以獲得曲折後可以回復且發電之複合膜。我們主要是要測試添加不同量之鈦酸鋇對P(VDF-TrFE)高分子晶相以及發電能力之影響。最後發現，添加越多鈦酸鋇奈米線者，曲折後可以產生越高的電壓。我們最多可以添加16% 體積分率之鈦酸鋇奈米線。所獲得之複合纖維膜發電效果為純P(VDF-TrFE)纖維膜四倍之多。

We have successfully fabricated a flexible nanofibrous mat of piezoelectric composite through the electrospinning of a P(VDF-TrFE) and BaTiO3 (BT) nanowire mixture. This mat forms a cost-effective and eco-friendly (lead-free) nanogenerator after encapsulated with PDMS. The P(VDF-TrFE) (poly(vinylidene fluoride trifluoroethylene) is known for its piezoelectric property and is employed as the matrix for our composite. The BaTiO3 nanowire was produced from the reaction of Ba(OH) with the titanate nanowire, which was synthesized through the hydrothermal treatment of TiO2 (Degussa P25) in 10M NaOH solution and HCl wash afterward. The BT material obtained have been characterized by X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and Raman Spectroscopy. The results show that the BT material is crystalline with tetragonal phase and has a one-dimensional morphology with average diameter of 110.6 nm and length of several micrometers.
The viscous composite formed by mixing BT and P(VDF-TrFE) in DMF/Acetone was electrospun into nanofibers and collected as a mat. The amount of BT nanowire in the composite could be as high as 16 vol%. The composite mat was cut into specific shape and size then encapsulated with PDMS after attached the electrodes. The open-circuit Voltage (Voc) of the nanogenerator assembled was evaluated under reciprocated bending. The composite nanogenerator generated more than four times the open-circuit voltage compared to that made from pure P(VDF-TrFE) nanofibers.

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