高效率之多元件堆疊結構有機太陽能電池

Abstract

本研究中我們利用多元件堆疊結構製作有機太陽能電池以達到高的功率轉換效率。其中半透明子元件採用三氧化鉬/銀的雙層結構製作反式半透明電極，主動層部分使用一個低能隙的高分子材料。之後我們嘗試在此透明元件之後堆疊上另一個具互補吸收之主動層材料子元件，利用吸收前面反式結構透明元件穿透之後剩下的光，將入射光達到最大吸收應用。另外在兩個子元件接面處塗佈可照紫外光硬化的的環氧樹脂，以消除接面處因空氣造成的折射率不匹配現象。將兩個元件串聯或並聯，由於兩個子元件具互補吸收，此多元件堆疊結構的整體能量轉換效率在標準量測環境下可達6.47%。 最後，著眼於未來軟性電子如要邁向實用化及商品化，在大面積製程上就必須要有所突破和發展。在此，我們採用了SMDPPEH/PC60BM做為主動層材料，在旋轉塗佈製程及刮刀塗佈製程下製作元件，在旋轉塗佈製程下效率可達4.42%，而在刮刀塗佈製程下效率可達4.02%。

In this work, we employed multiple-device stacked structures for organic solar cells for obtaining high power conversion efficiencies (PCEs). The semitransparent (ST) subcell adopted an inverted structure and the semitransparent anode was made of a MoO3/Ag bilayer electrode. The active layer was a low-band-gap polymer material. The second subcell featuring complementary absorptions was then stacked onto the ST device and two subcells were connected either in series or in parallel. UV-curable epoxy was further used to eliminate the air-gap and the mismatch of reflection indexes at the interface. Because the two subcells had complementary absorptions, the stacked structure exhibited an improved power conversion efficiencies (PCEs) of 6.47% under illumination at one sun. Additionally, small molecular-based bulk hetero-junction solar cell consisting of 2,5-di-2-(ethylhexyl)-3,6-bis-(5′′-n-hexyl – [2,2′,5′,2′′]terthiophen-5-yl) – pyrrolo[3,4- c]pyrrole-1,4-dione (SMDPPEH) and (1-(3-methoxycarbonyl)propyl-1-pheny[6,6]methanofullerene ([60]PCBM) were fabricated by both blade coating process and spin coating process. The PCE was 4.07%, almost as high as which was the efficiency obtained by spin coating process (4.42%).