本研究的目的為探討添加鋰鹽(LiTFSI)的聚(3,4-乙烯二氧?吩):聚苯乙烯磺酸(PEDOT:PSS:LiTFSI)並分別經過去摻雜劑(二甲基亞?)和還原劑(L-抗壞血酸)處理後，其微結構上的變化為何，與其是否影響熱電效率。我們利用小角度和廣角度X光繞射與散射、拉曼光譜和X光電子能譜進行量化分析，探討此系統微結構與其熱電性質的關聯性。藉由5 vol%二甲基亞?摻雜劑添加可有效提高PEDOT:PSS:LiTFSI薄膜賽貝克係數。此結果可歸因於鋰離子與二甲基亞?形成複合物時，會降低鋰離子與PSS的吸引力，造成 PEDOT晶粒尺寸變小與層間距變大(d(100)PEDOT)。再利用1wt% L-抗壞血酸作為還原劑，調控PEDOT:PSS的載子濃度對其進行還原反應，製備出在室溫下功率因子為24.6 μW m-1K-2的熱電薄膜。我們開發的熱電薄膜最大的特色在於可在人體有效溫差區間展現出12mV電壓並可應用於可撓式熱電元件。;The purpose of this study is investigation on thin-film microstructure of poly(3,4-ethylenedioxythiophene): polystyrene sulfonic acid: lithium salt (PEDOT:PSS:LiTFSI) affected its thermoelectric efficiency via Dimethyl sulfoxide (DMSO) de-doping and L-ascorbic acid treatment. We utilized small-angle and wide-angle X-ray diffraction and scattering, Raman spectroscopy and X-ray photoelectron spectroscopy for quantitative analysis, and explored the correlation between the microstructure of PEDOT:PSS:LiTFSI and its thermoelectric properties. The Seebeck coefficient of PEDOT:PSS:LiTFSI thin film can be effectively improved by adding 5 vol% DMSO de-dopant. This result can be attributed to that as lithium ions and dimethyl sulfide form a complex, the attraction between Li+ ions and PSS is reduced, resulting in a smaller PEDOT grain size and a larger interlayer spacing (d(100)PEDOT). We also used 1wt% L-ascorbic acid as a reducing agent to control the carrier concentration of PEDOT:PSS. After this treatment, high thermoelectric film with a power factor of 24.6 μW m-1K-2 at room temperature was performed. This designed PEDOT:PSS:LiTFSI thermoelectric film can exhibit a voltage of 12mV in the effective temperature range of the human body to be applied to flexible thermoelectric elements in the future.
