本實驗以P型材料聚(3-己烷噻吩)[Poly(3-hexylthiophene), P3HT]混摻N型材料茚-碳六十的雙加成物(Indene-C60 Bisadduct, IC60BA)作為主動層，利用添加劑與熱退火的方式調控主動層微結構，製作有機太陽能電池。主動層的主溶劑為氯苯，分別加入3 v%之二碘辛烷 (1,8-Diiodooctane, DIO)、二氯戊烷 (1,5-Dichloropentane, DCP)、二溴丁烷 (1,4-Dibromobutane, DBB)作為添加劑。利用X光繞射光譜儀、原子力顯微鏡、吸收光譜儀、光致螢光光譜儀與拉曼光譜儀等分析主動層薄膜，探討添加劑對主動層微結構變化與元件電性之影響，也進一步對主動層進行熱退火，探討加上熱退火後，主動層微結構變化對電性之影響。
元件電性分析結果顯示，在主動層未經熱退火的情況下，加入添加劑DBB、DCP與DIO後，元件的短路電流密度與填充因子皆獲得提升，但元件的開路電壓卻降低。將主動層進行熱退火後，元件的短路電流密度、填充因子與開路電壓均得到提升。
經由分析得知，主動層加入添加劑後，P3HT的縱向結晶稍微變長且結晶性變佳，主動層相分離程度變得明顯，主動層可形成有效的載子路徑，因此主動層微結構獲得改善，元件的短路電流密度與填充因子獲得提升。而非結晶的P3HT與IC60BA的交互作用變弱，非結晶P3HT之有效共軛鏈長變長，降低P-N接面的內建電場，使元件的開路電壓降低。其中主動層若加入較高沸點之添加劑DIO，產生的相分離程度較嚴重，非結晶P3HT與IC60BA的交互作用較弱，所以元件的電性都較主動層加入低沸點添加劑的元件差。
未加入添加劑的主動層進行熱退火後，P3HT的縱向結晶變長且結晶變好，結晶P3HT的均勻性變好，主動層可形成連續的載子傳輸路徑，因此主動層微結構獲得改善，提升了元件的短路電流密度與填充因子，而非結晶的P3HT與IC60BA的交互作用變弱，非結晶P3HT之有效共軛鏈長變長，使元件的開路電壓降低。加入添加劑的主動層進行熱退火後，P3HT的縱向結晶變長，主動層相分離程度降低，主動層的載子傳輸路徑變得更好，進一步改善主動層的微結構，所以元件的短路電流密度與填充因子能再一步提升，而非結晶的P3HT與IC60BA的交互作用變強，非結晶P3HT之有效共軛鏈長變短，使元件的開路電壓提升。其中主動層若加入較高沸點之添加劑DIO，產生的相分離程度降低，非結晶P3HT與IC60BA的交互作用較強，所以元件的開路電壓提升最多。

In this research, we discuss the influences of solvent additive and thermal annealing on the microstructures and electrical performance of organic solar cells (SCs). The poly(3-hexylthiophene):indene-C60 bisadduct (P3HT:ICBA) blend dissolved in chlorobenzene was adopted to fabricate the active layers of SCs. 1,5-Dichloropentane, 1,4-dibromobutane, and 1,8-diiodooctane were selected as solvent additives. After the addition of solvent additive or thermal annealing, the short circuit current density (Jsc), fill factor (FF), and power conversion efficiency (PCE) of SCs were increased while the open circuit voltage (Voc) was decreased. Furthermore, joint solvent additive and thermal annealing were able to simultaneously increase the Jsc, Voc, FF, and PCE of SCs. Atomic force microscopy, X-ray diffraction, absorption, Raman, and photoluminescence spectroscopy were used to analyze the microstructures of P3HT:ICBA. Either solvent additive or thermal annealing improve the crystallinity of P3HT and cause obvious phase separation to form continuous charge transport pathways resulting in the increased Jsc, FF, and PCE of devices. However, the extended effective conjugation length (Leff) of amorphous P3HT and obvious phase separation weakened the interaction between P3HT and ICBA, leading to decreased Voc of devices. Compared with single method, combined solvent additive and thermal annealing could improve the crystallinity of P3HT and help the formation of more proper phase separation, and leading to the enhanced Jsc, FF, and PCE of devices. Moreover, the reduced Leff of amorphous P3HT and alleviated phase separation strengthened the interaction between P3HT and ICBA, resulting in increased Voc of devices.

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