| 摘要: | 聚(3,4-乙烯二氧噻吩)：聚苯乙烯磺酸鹽(PEDOT:PSS)是一種常見的導電高分子材料，因其優異的光學透明性、柔韌性、環境穩定性及水溶性，在有機電子學領域中廣泛應用。然而，純PEDOT:PSS的導電度相對較低，主要受限於含絕緣性PSS的存在，且過量的PSS易於PEDOT外圍形成包覆層，阻礙鏈之間的有效接觸與電荷傳輸，成為提升導電度的重要障礙。
為改善PEDOT:PSS導電性，過去研究多聚焦於溶劑處理、添加劑摻雜、熱處理及酸洗等方式。然而，這些方法在實務應用上仍面臨挑戰，限制其大面積製程與穩定性表現。另外，過程中添加的化學溶劑需要進行廢液處理，具有環境汙染及環保疑慮，同時也會花費大量時間與成本。因此，開發一種在不需添加化學溶劑，不具汙染性的情況下，還能降低表面電阻，提高電導率的方法非常關鍵。
本論文採用簡易的處理方式，利用微波給予PEDOT:PSS中的極性分子快速震盪，將其中PEDOT與PSS進行部分相分離，並改善結構共軛性(conjugation)。此舉能有效PEDOT:PSS增加導電性(表面電阻降低50%以上)；另外，降低接觸角的同時(71.4°下降到32.9°)提高了黏滯係數，這樣的特性使PEDOT:PSS的成膜穩定性與可加工性有效提升。除了直觀的物理性質變化外，也利用顯微鏡和拉曼光譜分析中，分別確認微波前後PEDOT:PSS的結構與鍵結變化，說明了微波處理能簡單且快速地改善PEDOT:PSS特性。
;Poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS) is a widely used conductive polymer material in organic electronics, valued for its excellent optical transparency, flexibility, environmental stability, and water solubility. It finds applications in organic solar cells, organic light-emitting diodes, electrochromic devices, and sensors. However, the conductivity of pristine PEDOT:PSS is relatively low, primarily limited by the presence of insulating PSS. Excess PSS tends to form a coating layer around PEDOT, hindering effective contact and charge transport between polymer chains, which has become a major obstacle to improving conductivity.
To improve the conductivity of PEDOT:PSS, previous studies have focused on methods such as solvent treatment, additive doping, thermal processing, and acid washing. However, these approaches still face several practical challenges, which limit large-scale processing and stability performance. Additionally, the chemical solvents used during these processes need to deal with chemical waste disposal, raising environmental pollution concerns and cost time and money. Therefore, it’s important to develop a method that reduces surface resistance and enhances conductivity without using any chemical solvents or causing pollution.
This study proposes a simple treatment by using microwave to induce rapid oscillation of polar molecules in PEDOT:PSS, achieving partial phase separation and between PEDOT and PSS. It also partially changes the conformation of PEDOT chains,
which effectively enhances the conjugation of PEDTO and increases conductivity (surface resistance was reduced by over 50%). In the meantime, this process reduces the contact angle (from 71.4° to 32.9°) while increasing the viscosity coefficient, enhancing the film-forming stability and processability of PEDOT:PSS. Beyond the intuitive changes, microscopy and Raman spectroscopy analyses were also used to confirm structural and bonding changes in PEDOT:PSS before and after microwave treatment, demonstrating that microwave processing can simply and rapidly improve the properties of PEDOT:PSS. |
