熱電材料是一種有效將熱能轉換成電能的能源擷取方式，然而，在現今熱電領域的發展尚未完全成熟，提高熱電能量轉換效率及功率因子仍需要大量技術和人力的投入。本研究主要是探討在低溫環境下，利用富有良好熱電性質的導電高分子PEDOT:PSS為主體，透過摻雜不同重量百分比經純化處理後的奈米碳管形成奈米複合結構薄膜，建構出熱電性質最佳化的設計。透過純化奈米碳管的摻雜能將熱電薄膜的載子濃度和飄移速度分別提升至1.19E20 (cm-3)、311.3 (cm2/Vs)，進而讓導電率達到5929 S/cm，奈米複合結構薄膜運用能量過濾效應的特性使席貝克係數能在導電率顯著提昇的情況下維持在40-50 μVK-1，相較於只含PEDOT:PSS的薄膜，成功將熱電材料衡量效率的指標：功率因子( PF = σ2S )增加近200倍左右，達到1233 μWm-1K-2。本研究使用標準I-V量測方式及數據處理計算出溫差轉換電力的輸出功率，並以公式證明，熱電輸出功率與功率因子相比對下，可先行判斷薄膜熱電性質的優劣。另一方面，我們運用各種分析儀器深入了解PEDOT:PSS和奈米碳管混摻後結構演變的機制，詳細探討導電率和功率因子大幅上升的原因。本研究也試圖對薄膜進行磁場、電場的施加，控制奈米碳管於導電高分子基質中的排列及分散程度，其中經過薄膜施加交流電壓25V、2hr的處理，熱電輸出功率可由14.34 nW提高至20.17 nW、席貝克係數增加至50.2 μVK-1，說明奈米碳管越分散時，可使導電高分子與碳管接觸的接面增加，讓能量過濾效應的影響更為顯著，並提升席貝克係數。除此之外，本研究更於矽基板上使用金屬輔助化學蝕刻法建立一維結構的矽奈米線，發現薄膜的熱電輸出功率大幅上升至47.77 nW、席貝克係數也提升至63.2 μVK-1，初步推測是由各奈米結構中的接面，可使能量過濾效應的影響更加顯著，進一步提升熱電性質。

Applications of thermoelectric devices reveal that harvesting wasted heat and solar thermal energy into electricity have been anticipated to be renewable energy sources. In this study, the hybrid nanocomposites film is prepared that enable to convert the thermal heat into applicable electrical energy. PEDOT:PSS, known as exhibiting remarkable thermoelectric organic material, had been employed further by introducing the highly conductive carbon nanotubes as the fillers, which largely improve electrical conductivity (up to 5929 S/cm) without sacrificing Seebeck coefficient via nanoscale junction, which is also believed to play an important role in filtering low energy electrons (Energy filtering effect), resulting in large power factor, 1233 μWm-1K-2 at room temperature. The mechanism of CNTs/PEDOT:PSS blends are also observed by analysis instruments, explaining the reason how thermoelectric properties of conductive polymer film can be successfully improved by adding CNTs. In addition, applying electric and magnetic field to the nanocomposite film are further investigated, revealing that thermal output power based on simple equipped I-V measurement could be amplified from 14.34 nW to 20.17 nW. Furthermore, we propose an idea that the optimized nanocomposite film is deposited on the one-dimensional silicon nanowire substrate established by metal-assisted chemical etching. It is found that the output power and Seebeck coefficient are remarkably increased to 47.77 nW and 63.2 μVK-1 due to significant energy filtering effect created by energy barrier between nanoscale junction.

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