本實驗成功的製作出高效率的透明太陽能電池元件，下吸光時元件的 電性及效率可以達到Voc = 0.57 V、Jsc = 8.63 mA/cm2、FF = 0.565 以及 PCE
= 2.78 % ， 這 個 結 構 是 由 Glass/ITO(180 nm)/Cs2CO3/P3HT:PCBM(180 nm)/MoO3(5 nm)/Al(1 nm)/Au(14 nm)組成。此透明電極在可見光波段穿透 度約可達到50 %，且元件的 Rs、Rp仍可維持在不錯的範圍。將來可以將 我們的透明電極運用在串疊或是堆疊結構上，來提升有機太陽能電池的效 率。在商業應用上，我們可以將此透明有機太陽能電池製作在大樓玻璃 上，便可以達到最有效的空間利用，同時降低室內溫度和產生能源。在可 撓式基板的應用上，我們的透明有機太陽能電池可以選用不透明的金屬基 板，相較於一般透明的塑膠基板，在水氧隔絕性和基板耐熱度上能夠有比 較好的表現。
5.2 未來展望
本研究所表達的是利用目前現有的 P3HT: PCBM 材料來製作高效率 的透明有機太陽能電池，以及其延伸應用探討。但同樣的也因為 P3HT:
PCBM 的透光性不佳，將來若是發展出新的材料，其吸收光譜能夠不涵蓋 可見光的光譜，同時又具有很好的紅外光或是紫外光的吸收率，便可以在 不降低其效率的同時，增加透明太陽能元件應用在建築物表面的效應，達 到最大的空間應用。
雖然就目前高分子有機太陽能電池之光電轉換效率來說，已經可以達 到相當好的光電轉換效率，但由於 P3HT 能帶寬為 1.9eV，主要主吸收在 600 nm 光譜以下，而就太陽光譜來看，由圖 5-1 所示，有相當大的部份是 在大於600 nm 波長的能量分佈，因此，開發出新的低能帶寬高分子材料，
且能階與acceptor 相匹配，擁有高的載子遷移率是未來該領域的趨勢。
圖 5- 1 P3HT: PCBM 高分子薄膜的吸收光譜與太陽放射光譜的比較圖
另一方面，在追求高轉換效率的同時，材料本身的耐熱性、耐久性及 穩定性勢必也將成為未來有機太陽能電池符合商品實際應用上所必須面 對的問題。最後，希望本研究內容所提出的透明電極論點對國內外學術界 與相關產業將有所貢獻，並且在未來發展結合上述兩個提升轉換效率的方 法，期許有機太陽能電池能夠在日常生活中更普及化與更廣泛地應用。
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