高效率有機高分子太陽能電池之介面處理

Interfacial manipulations of high performance organic polymer solar cells

宋運明(Yun-Ming Sung)

指導教授 ： 陳永芳

國立臺灣大學/理學院/物理研究所/博士(2015年)

https://doi.org/10.6342/NTU.2015.10494

摘要

本論文主要研究高效率的有機太陽能電池。藉由不同的介面層處理以增進太陽能電池的效率。其處理方式包含材料與主動層的混摻、self-assembled monolayer(SAM)的形成以及電漿型奈米粒子的應用。所有元件皆在AM1.5狀態下進行量測。並藉由吸收光譜儀(Absorption spectroscopy)、IPCE (monochromatic incident photon-to-electron conversion efficiency)、原子力顯微鏡 (atomic force microscope)、時間解析螢光光譜 (Time resolved photoluminescence)、CELIV (charge extraction by linearly increasing voltage)、暫態之光伏特與電流量測 (Transient photovoltage and photocurrent)…等等進行詳細分析。以下是本論文之研究主題:
1. Enhanced photocurrent and stability of inverted polymer/ZnO-nanorod solar cells by 3-hydroxyflavone additive.
將3-hydroxyflavon (3-HF)與P3HT及PCBM混摻後，能量轉換效率(PCE)從2.57%增至3.05%。3-HF能改變主動層形貌並大幅增加載子遷移率，且3-HF的混摻能夠大幅增加有機太陽能電池在大氣下之穩定性，在本研究中我們藉由CELIV與原子力顯微鏡的量測研究3-HF對元件界面的影響。
2. Improved charge transport in inverted polymer solar cells using surface engineered ZnO-nanorod array as an electron transport layer.
主動層與電子傳輸層間的介面在影響元件效率中扮演了重要的角色。介面問題可能影響激子分離率與載子的傳遞…等等。在本研究中，藉由有系統結構之硫芳烴分子吸附在氧化鋅奈米柱上，進行電子傳輸層與主動層間的介面修飾以改善電子傳輸層與主動層的相容性。並藉由載子遷移率的量測，分析了硫芳烴分子對主動層奈米結構之影響。由於激子分離率並未有改變，因此我們將元件增幅的主要成因歸因於較平衡的載子傳遞。
3. Improving Performance of Polymer Solar Cells with Broad Band Plasmonic Nanomaterials
增加元件吸光能力是另一種增加效率的方式。增加吸光效率的方式有很多種，例如在元件內成長奈米結構或摻入散射材料…等等。在本研究中，我們在高效率PTB7有機太陽能電池內利用寬頻譜之電漿奈米粒子增加光在主動層內的散射，並由暫態之光電流及光伏特量測載子的遷移率及存活時間。藉由此奈米粒子的摻入，元件效率大幅的從8.02%增加至9.01%。

關鍵字

介面處理 ； 有機太陽能電池

並列摘要

This thesis mainly focuses on the study to obtain high performance organic solar cells using different methodologies of interlayer manipulations. The manipulations include the mixtures of additive materials and active layer, the formation of self-assembled monolayer (SAM) and the application of plasmonic effect of nanoparticles. All devices are measured under illumination in AM1.5 condition. The detailed analyses are measured by absorption spectroscopy, monochromatic incident photon-to- electron conversion efficiency (IPCE), atomic force microscope (AFM), time resolved photoluminescence (TRPL), charge extraction by linearly increasing voltage (CELIV), transient photovoltage and photocurrent, etc. The studied topics include:
1. Enhanced photocurrent and stability of inverted polymer/ZnO-nanorod solar cells by 3-hydroxyflavone additive.
After blending 3-hydroxyflavon (3-HF) with P3HT and PCBM, the device power conversion efficiency (PCE) has been improved from 2.57% to 3.05%. 3-HF also can modulate the morphology of active layer and then largely enhance carrier mobility. In addition, organic solar cell stability has been largely improved after 3-HF incorporation. In this topic, we study the effect in device interlayer which is affected by 3-HF is studied by using CELIV and AFM.
2. Improved charge transport in inverted polymer solar cells using surface engineered ZnO-nanorod array as an electron transport layer.
Interlayer between active layer and electron transport layer plays an important role in determining the device performance. The interlayer conditions can affect excitons separation rate and carrier transport, etc. In order to improve the compatibility of active layer and electron transport layer, we modify the interface between electron transport layer and active layer by adsorbing systematic thioaromatic molecules on ZnO nanorods. We also analyzed the nanostructure change of active layer which is affected by thioaromatic molecules by using carrier mobility measurement. According to the negligible change of excitons separation rate, we attribute device enhancement to more balanced carrier transport.
3. Improving Performance of Polymer Solar Cells with Broad Band Plasmonic Nanomaterials
Increasing device light absorption ability is another method for increasing efficiency. There are many kinds of method for increasing light absorption ability such as growing nanostructure in device or incorporating scattering materials, etc. In this topic, we use broad band plasmonic nanoparticles to increase light scattering in active layer in high performance PTB7 based organic solar cell. We also study carrier mobility and lifetime by using transient photovoltage and photocurrent. After incorporating these nanoparticles, the device power conversion efficiency has been largely improved from 8.02% to 9.01%.

並列關鍵字

Interfacial manipulations ； organic polymer solar cells

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