本研究主要在開發碳黑-PEDOT複合對電極，並將其應用於在銅錯合物電解質的染料敏化太陽能電池。首先合成銅錯合物氧化還原對，並對其電解質組成進行優化，進而探討碳黑、PEDOT及碳黑-PEDOT對電極對此一系統光電轉換效率的影響。研究結果發現使用化學氧化法可得到較為純淨的銅二價錯合物，此外在電解質添加劑的實驗中發現使用NMBI所得的電池效率較使用tBP高，這是因為NMBI分子可以降低光電極/電解質界面的電荷再結合行為。本研究的結果發現電解液最佳組成為0.2M Cu(dmby)2TFSI、0.06M Cu(dmby)2(TFSI)2、1.1M NMBI及0.1M LiTFSI，利用此一組成配合PEDOT對電極所得的電池效率可達9.31%。若使用碳黑作為對電極，其所得元件效率8.58%會低於PEDOT對電極，藉由循環伏安法分析發現碳黑對電極的還原峰位置與數目與PEDOT不一致，推測這是銅錯合物在此二材料還原反應機制不同所導致的。雖然碳黑作為對電極的催化效果不如PEDOT，但其有大表面積的優點，因此本研究中我們以碳黑作為導電底材，再於其表面上聚合PEDOT，製作碳黑-PEDOT複合對電極。在Dummy cell的分析中得知此複合對電極具有比PEDOT更低的電荷傳輸阻力及更高的交換電流密度，顯示其較好的電催化能力。在循環伏安法的分析中亦發現複合對電極之氧化、還原峰電流皆高於PEDOT對電極，表示電催化能力的提升與其表面積變大有關。利用碳黑旋塗次數及PEDOT聚合條件的調整發現，旋塗兩次碳黑並以定電位0.9V (v.s Ag/AgCl)聚合40秒之複合對電極可達最佳效率10.08%。此複合對電極之電池元件於室溫避光下進行穩定性測試，在525小時後元件效率可維持其最大值的96.9%，顯示此複合對電極具有高的穩定性。

This study focuses on developing carbon black-PEDOT composite counter electrodes and applying them to dye-sensitized solar cells employing copper complex electrolytes. It includes the discussion about the effects of carbon black counter electrode, PEDOT and carbon black-PEDOT counter electrode on copper complex electrolyte. The experiment results shows that the efficiency of the DSSC with carbon black counter electrode is 8.58% lower than that of the PEDOT counter electrode(9.31%). By cyclic voltammetry analysis, it’s found that the position and number of the reduction peaks of the carbon black counter electrode are inconsistent with those of PEDOT. This may be caused by the different reduction reaction mechanisms of the two materials. Therefore, in this study, we utilize the large surface area of carbon black and let it be a conductive substrate for polymerizing PEDOT to fabricate carbon black-PEDOT composite counter electrode. In the Dummy cell analysis, it shows that the composite counter electrode has lower charge transport resistance and higher exchange current density than PEDOT. In the analysis of cyclic voltammetry, it's also found that the oxidation and reduction peak currents of the composite counter electrode are higher than PEDOT. It means composite electrode has good electrocatalytic ability. By adjusting the number of carbon black spin times and PEDOT polymerization conditions, the composite counter electrode that was spin-coated with carbon black twice and polymerized at constant potential of 0.9V (v.s Ag/AgCl) for 40 seconds can achieve the best efficiency of 10.08%. The cell stability test is operated at dark and room temperature. After 525 hours, the cell efficiency could maintain 96.9% of the maximum value. It indicates that the composite counter electrode has high stability.

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