高效率及高穩定之高分子太陽能電池：碳六十衍生物之設計與合成

Abstract

本計畫將會提出三個方向來實現高效率以及高穩定性之有機高分子太陽能電池，首先我 們將設計合成一系列可熱交聯之富勒烯衍生物，並將其混掺在N-型與P-型材料中，此 薄膜在適當的加熱過程中可得到型態之最佳化進而達到最佳的元件效率，之後再透過升 高溫度來誘發聚合反應，藉由化學鍵的生成來固定最佳化的型態並且維持元件的穩定 度。反式太陽能電池已被公認比傳統結構具有更好的元件壽命，然而反式太陽能電池的 效率卻明顯的較正結構差，主要是由於介面之間的能階與化學特性不相容性，因此在第 二個主題中，我們將會設計合成一系列新穎之富勒烯衍生物，此類材料能夠透過在金屬 氧化物表面上的自組裝進而鈍化表面上的電子陷阱，同時能夠進行分子間縱相的交聯反 應形成堅固且多分子的中間層，以期可大幅提升元件的效率。最後我們將會著重在 N- 型材料的分子工程修飾來提升分子的LUMO 能階以期增加元件的開路電壓，我們將利 用模板誘導反應來實現化學反應位相之選擇性，並且得到單一異構物之碳六十雙加成衍 生物，如此一來可以改進因異構物的存在而造成的電子能階陷阱之效應。

In this proposal, we will bring up three sub-projects to realize highly efficient and stable polymer solar cells. First, a series of thermally cross-linkable fullerene derivatives will be designed and synthesized. These materials will be doped into donor/acceptor blending systems. After the optimal morphology is first induced under mild thermal annealing to obtain high performance, we will then trigger the polymerization reaction at higher temperature to chemically fix the morphology to preserve the stability. Inverted solar cells have been known to possess better device stability than traditional ones. However, the performance of inverted solar cells is inferior due to the unfavorable energetic and incompatible chemical interfaces. In the second sub-project, we will develop a series of novel fullerene materials which can self-assemble onto the surface of metal oxide to passivate the surface traps, followed by vertical intermolecular cross-linking reaction to form a robust and multi-molecular layer, overcoming the trade-off between performance and stability. Finally, we will focus on molecular engineering of fullerene n-type materials in order to rise up their LUMO energy levels and thereby improve the Voc. In this project, we will use an approach of “tether-directed remote functionalization” to the regio-selective formation of bis-adducts of C60 so that electron-trapping effect can be eliminated.