本研究探討以非溶解性溶劑和溶解性溶劑作為的混溶劑對薄膜結構及其相對應有機太陽能電池的電特性之影響，其中太陽能電池元件以聚(3-己烷基噻吩)(poly(3- hexy lthiophene), P3HT)和碳六十衍生物([6,6]-phenyl-C61-butyric acid meth yl ester, PCBM)為主動層材料。本研究選擇醇類作為非溶解性溶劑，氯仿(CF)為溶解性溶劑，其中醇類選用乙醇(低沸點醇類)和正丁醇(高沸點醇類)，藉由摻入不同比例的醇類於CF中製備P3HT:PCBM的薄膜，搭配吸收光譜儀、拉曼光譜儀、 X光繞射儀和原子力顯微鏡對薄膜進行相關分析，並進一步分析其相對應太陽能電池元件的電特性。
由吸收光譜和拉曼光譜的分析可發現，摻入乙醇或正丁醇於CF後， P3HT結晶區域的有效共軛鏈長皆有明顯變長、結晶區域的比例明顯增加和P3HT結晶區域的均勻性也獲得提升；在原子力顯微鏡下可觀察到，P3HT和PCBM出現明顯的相分離，使得P3HT區塊明顯的變大。另外，原子力顯微鏡下也可觀察到，P3HT區塊間也有較明顯的聯繫。元件電性結果顯示，元件電性結果顯示，當摻入乙醇的比例為8 v%時，FF值由0.44提升至0.59，而當摻入較小比例的正丁醇後，其FF值也同樣有明顯的提升。綜合薄膜分析與電性結果可知，摻入醇類可有效的調整薄膜結構，在主動層內產生一個有利載子傳輸的路徑，減少載子在傳輸過程的損耗，進而提升有機太陽能電池的FF值。
本研究也比較了摻和不同的醇類(乙醇和正丁醇)對於對薄膜結構及其有機太陽能電池電特性的影響。從相關的薄膜分析結果及電性結果顯示，相對於相同比例的乙醇，正丁醇的摻入對於P3HT:PCBM的薄膜結構上的改變影響較大，推測可能由於旋轉塗佈主動層材料的過程中，醇類在溶劑中所佔的體積百分受到沸點高低的影響而改變。

The influence of the mixture of good and poor solvents for preparing the active layers of poly(3-hexylthiophene) (P3HT):fullerene derivative [i.e., [6,6]-phenyl-C61-butyric acid methyl ester (PCBM)] on the photovoltaic properties of polymer bulk heterojunction (BHJ) solar cells were investigated. Chloroform and alcohol were chosen as the good and poor solvents, respectively. Two types of alcohols were used, namely, ethanol with a low boiling point (bp) and butanol with a high bp. The different amounts of alcohol were introduced into the chloroform to prepare the P3HT:PCBM blending films. The active layers were studied by absorption spectroscopy, Raman spectroscopy, X-ray diffraction, and atomic force microscopy (AFM). The correlation between the microstructural properties of the active layers and photovoltaic properties of the polymer BHJ solar cells was also examined.
With regard to the microstructural studies on P3HT:PCBM blending films, the absorption and Raman spectroscopy results revealed that incorporating ethanol or butanol into chloroform resulted in a significantly longer effective conjugation length (Leff) of the P3HT chains in the crystalline region, considerable increases in the proportion of crystalline regions, and improved uniformity of the P3HT crystalline region. AFM analysis results suggest significant phase separation between P3HT and PCBM, and a larger P3HT grain. For the photovoltaic properties, the fill factor (FF) value particularly improved from 0.45 to 0.59 when 8 v% ethanol was incorporated into the chloroform. The improved FF value was also observed in the chloroform:butanol cases when a smaller proportion of butanol was introduced. In summary, incorporating alcohols into the chloroform effectively adjusted the structure of the active layers, thereby providing better pathways for reducing the loss of charge carriers during transportation and raising the FF value of polymeric BHJ solar cells.
Finally, this study investigated the effect of incorporating different alcohols into the chloroform on the active layer structure of P3HT:PCBM and the photovoltaic properties of BHJ solar cells. We found that butanol addition into the chloroform imposed a more substantial effect on the microstructure than did ethanol addition. We propose that the bp of alcohols plays an important role in the formation of the active layer microstructure during spin coating.

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