共軛高分子熱電材料的結構設計與機制探討

Abstract

熱電材料可直接將熱能轉換為電能，為收集低階廢熱提供了一項相當具有前途的解決途徑。在各種熱電材料系統中，有機共軛高分子因其固有的柔軟性和低熱傳導係數受到越來越多的關注。然而，目前尚對其分子結構與各項性質(如材料的介面性質、熱電性能、與機械性能)之間的關係瞭解不足，導致這類材料的應用仍受到限制。本論文透過三個研究項目，探討分子設計策略對於熱電性能及薄膜拉伸性的影響，期望提供對於分子層面的瞭解。 第一項研究利用由共軛的聚(3-己基噻吩) (P3HT)與絕緣的聚(丙烯酸正丁酯) (PnBA)組成的金屬超分子嵌段高分子，著重探討嵌段結構如何影響高分子奈米級形貌、摻雜效率以及摻雜高分子薄膜的拉伸性。 第二項研究為拓展對於三(五氟苯基)硼烷(BCF)布忍斯特酸摻雜效果的應用與瞭解，利用聚[3,4-二(2-乙基己基)噻吩乙烯] (P3,4EHTV)、聚[3-(2-乙基己基)噻吩乙烯] (P3EHTV)和聚[3-(乙基己基)噻吩] (P3EHT)三種共軛高分子，以探討高分子共軛主鏈和側鏈工程對於摻雜行為和電荷傳輸的影響。 第三項研究開發了一系列以P3,4EHTV為基礎的二嵌段高分子，其中結合了不同極性的絕緣鏈段(聚環氧乙烷(PEO)、聚苯乙烯(PS)和聚五氟苯乙烯(PFS))，以控制高分子的聚集結構並改善單壁奈米碳管(SWCNT)在高分子溶液中的分散。本研究利用溶液態散射和光譜分析，探討高分子聚集結構對於材料介面的相互作用及奈米碳管分散性，以及進一步探討介面作用力對於複合物薄膜的拉伸性。 這些研究共同為下一代軟性熱電材料應用提供了結構與性能相互關係的觀點，以及提供了開發高性能和可拉伸的有機熱電材料的材料設計準則及方向。

Thermoelectric materials, which enable direct conversion of heat into electricity, offer a promising route for harvesting low-grade thermal energy. Among various thermoelectric systems, organic conjugated polymers (CPs) have attracted increasing attention due to their intrinsic mechanical flexibility and low thermal conductivity. However, their widespread application remains limited by insufficient molecular-level understanding of the structure–property relationships that govern thermoelectric performance, mechanical stretchability, and interfacial behavior across diverse material systems. This thesis addresses these challenges through three thematically connected studies that explore molecular design strategies to improve the performance and understanding of polymer-based thermoelectric systems. The first study investigates metallo-supramolecular block copolymers composed of poly(3-hexylthiophene) (P3HT) and poly(n-butyl acrylate) (PnBA), focusing on how block architecture modulates nanoscale morphology, doping efficiency, and mechanical deformability of the doped polymer thin films. The second study examines Brønsted acid doping effect using tris(pentafluorophenyl)borane (BCF) in poly[3,4-di(2-ethylhexyl)thienylene vinylene] (P3,4EHTV), and compares its behavior to poly[3-(2-ethylhexyl)thienylene vinylene] (P3EHTV) and poly[3-(ethylhexyl)thiophene] (P3EHT). This project amins to reveal how molecular engineering in polymer backbone and side chain influence doping behavior and charge transport property. The third study develops a series of P3,4EHTV-based diblock copolymers incorporating insulating blocks of varying hydrophobicity (poly(ethylene oxide) (PEO), polystyrene (PS), and poly(pentafluorostyrene) (PFS)) to control polymer aggregation and enhance single-walled carbon nanotube (SWCNT) dispersion. Using solution-state scattering and spectroscopic analysis, this work establishes how aggregation structure impacts interfacial interactions, SWCNT dispersion, and strain tolerance in composite thin films. Together, these studies offer structure–property perspectives and guiding principles for the rational design of high-performance, stretchable organic thermoelectric materials for next-generation soft energy harvesting applications.