溶劑的選擇與使用方式對高分子有機太陽能電池來說非常重要，同樣以P3HT與PCBM作為高分子有機太陽能電池主動層材料，製作基本結構 (Glass/PEDOT:PSS/P3HT:PCBM/Al) ，使用不同的溶劑塗佈主動層與進行溶劑退火會產生不同的效果。本論文透過調變主動層旋轉塗佈的過程、轉速以及退火溫度對基本結構進行元件特性參數的最佳化。
接著等比例混和tetralin與氯苯、tetralin與二氯苯以及調變tetralin與二氯苯的比例做為主動層溶劑使用，發現溶劑中摻有tetralin對短路電流有輕微提升，但卻大幅降低開路電壓；tetralin比例的增加減少了P3HT的結晶性，在tetralin比例達70%時則增加了PCBM傳遞載子的有效路徑。
最後用二氯甲烷、氯苯、二氯苯與tetralin進行溶劑退火，不同溶劑的溶劑退火對填充因子影響較明顯，其中經二氯甲烷溶劑退火的元件填充因子可達0.6以上，光電轉換效率可達3.3%，再經熱退火後填充因子達到0.7，光電轉換效率則達到4%。

Solvent application is very important for polymer solar cells. This work take P3HT and PCBM as active layer and fabricate basic polymer solar cells (Glass/PEDOT:PSS/P3HT:PCBM/Al). Various solvents influence the characteristic parameter in spinning active layer and solvent annealing. At first, the optimization of basic device was presented by spin process, spin speed and annealing temperature.
Then we mixed tetralin, chlorobenzene, and dichlorobenzene as the solvent of active layer. Tetralin in solvent promoted short circuit current slightly but decreased open circuit voltage dramatically. More tetralin in solvent decreased crystallinity of P3HT and increase effective carrier transport of PCBM as tetralin=70%.
Finally, solvent annealing with dichloromethane(DCM), chlorobenzene(CB), dichlorobenzene(DCB), and tetralin was studied. Various solvent impacted fill factor brilliantly. OPVs that were solvent annealed by dichloromethane (DCM) showed marked improvement of the fill factor (>60%), increasing the power conversion efficiency (PCE) to ~3.4%. The PCE of the DCM-annealed device increased to ~4% by thermal annealing.

[1] 資料來源：台灣電力公司http://www.taipower.com.tw/
[2] 資料來源：中央氣象局http://www.cwb.gov.tw/
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