本研究利用白金與聚3,4-乙烯二氧噻吩(PEDOT)作為染料敏化太陽能電池的對電極材料，在鈷錯合物氧化還原對系統中，探討對電極材料極其使用量對於電池在室內光環境中效能之影響。在白金對電極的製作上，藉由濺鍍時間的調控來製備不同厚度的白金薄膜。實驗結果顯示，當濺鍍時間自105秒減少至15秒，白金的沉積量下降，由電化學阻抗分析顯示，電極與電解液界面間的電荷傳輸阻力亦降低，其相對應電池有較高的短路電流。在螢光燈強度200 lux之照射下，電池轉換效率可由20.6% (105秒)提升至22.6% (15秒)。
此外，本研究亦利用定電流聚合法來製備PEDOT對電極，並藉由不同反應時間來調控PEDOT的沉積量。結果發現，當反應時間大於90秒後，電極上的高分子會產生團聚現象。阻抗分析結果則顯示，愈長聚合反應時間所量測到的離子擴散阻力愈大，因此電池的短路電流會隨著PEDOT量的增加而下降。當反應時間由130秒縮減至5秒時，電池在螢光燈環境中的轉換效率可自20.3%提升至23.9%。由於前述低含量Pt及PEDOT (濺鍍及反應時間5秒)的電極在可見光區域具有70%以上的穿透度，因此本研究進一步利用這些對電極製作可雙面照光之染敏電池。在室內光環境中，當光線由光電極側(正向)與對電極側(背向)入射時，使用高透光PEDOT電極的電池可分別達到19.9%與16.1%之轉換效率，而使用高透光白金電極的電池則呈現轉換效率分別為20.6%與17.3%，此兩種電池在背向與正向照光下的效率比值皆可達到0.8以上。

The main purpose of this study is to optimize the dye-sensitized solar cell (DSSC) parameter by using platinum (Pt) and poly(3,4-ethylenedioxythiophene) (PEDOT) counter electrode of under indoor lighting condition. DSSC based on the cobalt redox couples and commercial Y123 dye are fabricated. In terms of Pt materials, this study prepared electrodes with different Pt catalyst amounts by fixing the sputtering current (40 mA) and adjusting the sputtering time. The results show that as the sputtering time decreases from 105 seconds to 15 seconds, the charge transfer resistance between the electrode and the electrolyte interface decreases, so that a better catalytic effect of the electrode can be obtained. Under the illumination of 200 lux, the efficiency can be increased from 20.6% to 22.6%. In addition, this study also used a chronopotentiometry method to prepare PEDOT counter electrode, and regulate the amount of catalyst by different reaction time. The impedance analysis results show that the longer the reaction time is, the larger the ion diffusion resistance is measured. Therefore, the short-circuit current of the DSSC will show the opposite trend with the increase of the amount of the catalyst. The efficiency of the DSSC in a fluorescent lamp environment can be increased from 20.3% to 23.9%. A low-catalyst electrode is further applied to prepare a bifacial DSSC. In a room light condition, when light is incident from the photoanode side (forward) and the counter electrode side (backward), the cells using the high-transmission PEDOT electrode can achieve efficiencies of 19.9% and 16.1%, respectively. The cells with light-transparent Pt electrodes showed efficiencies of 20.6% and 17.3%, respectively, and the efficiency ratios of the two cells in the back and forward illumination are all above 0.8.

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