本篇論文主要探討PEDOT:PSS、石墨烯與奈米碳管作為主要材料製作的熱電元件之特性。在實驗開頭，我們分別探討PEDOT:PSS的DMSO摻雜效應對於薄膜內部結構與電性之變化以及多層膜結構使PEDOT產生極化改變，對於導電度與Seebeck常數的影響。接著我們嘗試引入石墨烯探討與PEDOT:PSS之間電性上的影響，藉由旋塗(spincoating)與滴鑄(dropcasting)兩種方法，觀察石墨烯的分散對整體薄膜熱電效應之作用，然後改以奈米碳管與PEDOT:PSS以疊層和混合的方式，觀察兩種材料如何影響彼此之熱電效應。最後，我們獨立探討奈米碳管之成膜特性對於其導電度影響，接著再以p型、n型材料摻雜，發現可能影響碳管內部載子濃度，因此能夠改變其熱電特性。

In this thesis, we tried to investigate the thermoelectric effects of PEDOT:PSS and its composite materials. In the first part, we used three different methods to enhance the conductivity of PEDOT:PSS films, observing how Seebeck coefficient was affected by these methods. In the next part, we mixed PEDOT:PSS with graphene and single-walled carbon nanotube(SWCNT) respectively, and we found that sufficient graphene in PEDOT:PSS film could form carrier conduction paths to enhance carrier mobility but didn’t affect its Seebeck coefficient. But we realized that SWCNT couldn’t disperse in PEDOT:PSS solution, so the interaction between these two material was investigated in a sandwich structure. We knew that the Seebeck coefficient would be affected by the conductivities of both materials, and would approach to the higher one. In the last part, we investigated the thermoelectric effects in SWCNT, and used different type of materials doping SWCNT. Then we found Seebeck coefficient increased and conductivity decreased, and it implied the carrier concentration of SWCNT might be affected by doping.

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