本研究主要目的為利用相當新穎之超臨界流體技術來製造用於超級電容之二硫化鉬奈米複合材料，提原本商用二硫化鉬之電容性質。首先為剝離二硫化鉬使其成為單層或少層結構，隨著壓力的增高，將得到更高品質之少層二硫化鉬，此外自X光光電子能譜中可以發現，超臨界二氧化碳在剝離二硫化鉬的同時，會使將近一半的二硫化鉬從原本之2H相轉變成1T相，提升其導電度，進而提升其超級電容性質。另試著加入兩種不同之三氧化鉬粉末，可以從SEM及TEM中得知商用之三氧化鉬其微米等級大小之粉末難以藉由超臨界流體帶入二硫化鉬之內層中，相對地，使用微波水熱所製成之奈米等級大小之奈米板狀粉末，就能夠被帶入內層間，形成複合材料，其三氧化鉬能夠提供複合材料氧化還原的反應，給予材料擬電容的性質，因此大幅地提高其電容值至38.5 mF cm-2。除此之外，也可以透過超臨界反溶劑法，快速地一鍋合成二硫化鉬/P3HT奈米複合材料。將二硫化鉬和P3HT混於有機溶劑中後放入超臨界流體實驗系統，藉由超臨界二氧化碳的協助，P3HT將會被帶入二硫化鉬層間，此外由於P3HT在二氧化碳中的溶解度不高，因此它將的均勻地於各層中析出，形成片狀二硫化鉬間鑲嵌著P3HT奈米線之複合材料，其P3HT同樣地將給予材料擬電容性質，顯著地提高其電容值至54.8 mF cm-2。我們將所製成之奈米複合材料作為超級電容之電極，進行循環伏安法、EIS及恆電流充放電分析來探討其電化學電容器之性質。

In this study, we use a novel, facile and one-pod method to exfoliate and synthesize MoS2 nanocomposites with supercritical CO2. Because of scCO2 has some unique properties and has both gas and liquid phase properties at the same time, so it can intercalate inside the MoS2 interlayers easily. MoS2 could be exfoliated to few layers or even single layer by scCO2. Hence, the surface area would be improved, increasing the EDLC behavior. In the same time, almost half MoS2 2H semiconductor phase would convert to the 1T metallic phase with the impregnation of CO2 in the interlayers. The synthesized MoO3 could successfully be intercalated inside MoS2 during the SCF process. P3HT nanowires could also be embedded and well distributed in MoS2 using supercritical anti-solvent technique. MoO3 and P3HT could give MoS2 pseudocapacitance and preventing MoS2 nanosheets restack after the exfoliation. So the electrical performance of these nanocomposites were highly improved.

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