本研究在利用以轉印法製備具雙極矩氧化鋅中間層應用於塊狀異質結構之層疊式有機太陽能電池(Organic bulk hetero-junction tandem solar cells)，藉由具相反極性的自組裝單分子層薄膜修飾氧化鋅中間層之兩側表面，並探討氧化鋅中間層表面極性的強度及方向於層疊式有機太陽能電池中載子傳遞及再結合性質對於元件效率的影響。
藉由氧化鋅奈米粒子(ZnO NPs)及霧化裂解法(SP-ZnO)製備之薄膜氧化鋅作為中間層基材，並成長具相反極性的自組裝單分子薄膜(Self-assembled monolayers, SAMs)於氧化鋅兩側表面，根據不同氧化鋅結構型態分析自組裝分子薄膜的成長方式及表面偶極矩的變化。本實驗使用具電洞傳導性質的自組裝單分子薄膜4-(trifluoromethyl)benzylphosphonic acid (CF3BPA)及相對應極性的自組裝單分子薄膜4-Methoxybenzoic acid (OCH3BA)於下電池/中間層及中間層/上電池介面之修飾。根據自組裝單分子薄膜的能帶改變，促使提升層疊式太陽能電池中間層載子的再結合率，進而提升元件整體效率。
由相反極性的SAMs於SP-ZnO與ZnO NPs上作為層疊式有機太陽能電池之中間層，並利用轉印的方法製作中間層，使氧化鋅其具有雙極性特性。雙極性氧化鋅中間層能調整氧化鋅表面之功函數，進而促使電子電洞結合。因此，在元件效率上能有效提升Voc與FF。

In this study, we utilize transfer-printing method for ambipolar ZnO film in inter-connecting layer of organic bulk hetero-junction tandem solar cells by modifying two sides of ZnO surface with opposite dipole. We study the dipole and direction of SAMs on ZnO surface, and also study for its effect to charge transport and recombination in the device performance of tandem solar cell.

By utilizing intermediate layer (IML) with zinc oxide nanoparticles (ZnO NPs) and ZnO film by Spray methods (SP-ZnO), which passivated opposite dipole SAMs on both sides for P3HT-based homo-tandem polymer solar cell. Comparing the difference of SAMs on different structure of ZnO surface. For the charge recombination IML, the SAMs attach on ZnO surfaces cause an “ambipolar” property. We exploit 4-(trifluoromethyl)benzylphosphonic acid (CF3BPA) and 4-Methoxybenzoic acid (OCH3BA) for hole and electron injection, respectively. The ambipolar IML can adjust the surface work function, which align the energy level, further improve the charges recombination in the ZnO films then the fill factor enhanced. Furthermore, we use water transfer-printing approach for amibipolar IML and rear sub-cell to tandem polymer solar cell. With ambipolar IML, the open circuit voltage (Voc) of tandem polymer solar cell can reach almost twice higher than single solar cell.

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