堆疊式有機太陽能電池與石墨烯陰極太陽能電池之研究

Abstract

本論文研究一些界面改質的方法，利用這些改質方法，堆疊式有機太陽能電池與石墨烯陰極太陽能電池得以以濕式製程製作出來，並探討元件最佳化過程與界面改質前後的性質變化。 本論文第一部分先討論主動層材料選擇，將其製作成單層太陽能電池並最佳化，接著討論堆疊式太陽能電池的中間連接層性質與適合的材料，為了讓中間連接層可以以濕式旋轉圖佈方式成膜，紫外光表面處理(UV-Ozone)與氧電漿表面處理(O2 plasma)被應用在主動層表面，改善其疏水的性質。堆疊式太陽能電池的主動層厚度設計過以得到相匹配電流，原件成功做出並達到5.129%的效率。被紫外光臭氧與氧電漿處理過的主動層表面進一步以儀器量測表面性質的變化，並且找到為何以紫外光表面處理的元件會表現不好的原因。 本論文第二部分研究以石墨烯當做陰極的倒置型單層太陽能電池，為了改善石磨烯表面疏水的性質，一種親疏水介面材料HBC-6ImBr被用來改變石墨烯表面性質，借由連續堆疊三層石墨烯，以PTB7:PC71BM為主動層的石墨烯陰極太陽能電池達到3.515%的效率。

In this thesis, several ways of surface modification are investigated. Tandem polymer solar cells and single junction solar cells with graphene as cathode are successfully fabricated via surface modification. The performance of solar cells and the property change after surface modification are carefully studied. In the first topic, we discuss the candidate materials for tandem solar cell. Single junction solar cells are optimized based on our front cell and rear cell material. Interconnection layer is then discussed. In order to let interconnection layer be coated on active layer, two commonly-used surface modification methods, UV-Ozone and O2 plasma, are introduced. Tandem solar cells are carefully designed and put into experiment. Devices are successfully fabricated with PCE of 5.129%. The surface properties of polymer film after UV-Ozone and O2 plasma pretreatment are further investigated. The reasons for poor performance of UV-Ozone-modified devices are found In the second topic, a single junction solar cell based on graphene cathode is fabricated. Hydrophobicity of graphene is improved with the aid of HBC-6ImBr. Three layers of graphene are transferred on glass substrate as cathode, and PCE of 3.515% is achieved based on PTB7:PC71BM.