鹵素鍵對高分子太陽能電池之穩定性的顯著提升

Abstract

在這篇論文中我們提出一個全新的方法去增進有機高分子太陽能電池的穩定度。為了提升穩定度，必須使主動層形貌維持在特定最佳狀態，因此我們設計利用添加一小分子3F3I和高分子材料之間的鹵素鍵作為維持形貌的作用力。接著，我們藉由EI-MS與XPS證明了3F3I於主動層薄膜中的存在，且最後總量與添加濃度有關。利用FTIR與XPS的訊號位移說明3F3I與高分子之間的鹵素鍵，同時配合DFT計算發現實驗結果與計算相符，由此可證明3F3I的確可與高分子材料之間產生鹵素鍵，而鹵素鍵也確實會減少主動層形貌變化，表現在元件效率上能明顯看到有抑制效率衰退的功效。

We report the interaction of halogen bonding to reinforce the BHJ morphology in polymer solar cells (PSCs) and enhance the device stability. In our scheme, 3F3I was chosen as a halogen-bond donor (C-I) that interacts with polymers providing carbonyl acceptors. Careful analyses of I 3d5/2 ionization energy and C-I stretching frequency render clear evidence of halogen bond formation. As a result, the excellent performance of PSCs can preserve around 90% PCE after 48 days with a variety of 3F3I concentrations. We thus demonstrate for the first time the exploitation of halogen bond to greatly boost the stability of PSCs upon retention of its initial efficiency.