摘 要：近些年来，可溶液处理的本体异质结（BHJ）有机太阳能电池由于具有质轻、柔性好、成本低以及可通过印刷进行大面积制造等优点，已经得到了研究者们广泛的关注。研究化学结构-光谱和能级-器件性能三者之间的关系对于通过分子设计进一步提高光伏性能是非常重要的。而相比于共轭聚合物，小分子展现了更多独特的优点，例如结构明确、纯度高、能级易于调控以及器件性能无批次差异。所以，小分子更有利于研究分子结构与性能之间的关系。

本论文的工作以二噻吩并噻咯（DTS）为中心给体单元设计合成了D1-A-D2-A-D1型小分子给体材料DTBTDTS，系统地研究了该分子的热学、光学、电化学性质以及器件性能的影响。该化合物都具有良好的热稳定性，在可见-近红外区域都有较宽的吸收和较高的吸光系数。此外，相比于联噻吩，在两个噻吩中间引入乙烯基的反式联噻吩有着更长的有效共轭长度，带隙更窄；然而乙烯基的引入降低了三个化合物的溶解性，导致在器件制备过程中活性层的成膜性较差，器件的能量转化效率不理想。

关键词：有机太阳能电池； 小分子； 给体材料

Abstract：Solution-processed bulk heterojunction (BHJ) organic solar cells (OSCs) have attracted intense attention in recent years due to their noteworthy merits, such as low cost, light weight, ease of large-area fabrication by roll-to-roll printing and flexibility. Compared with the conjugated polymers, small molecules possess some unique advantages, such as well-defined molecular structures, high purity, easier energy level control, simple synthetic procedures and high reproducibility. They are supposed to be good candidates for investigating the relationship between chemical and structure-photovoltaic performance, which is highly important for further molecular design to achieve higher photovoltaic performance.

New D1-A-D2-A-D1 type small molecules DTBTDTS with 4,4-dioctyl-4H-silolo[3,2-b:4,5-b']dithiophene as core units has been designed and synthesized. The optical, thermal, electrochemical properties and device performance has been studied. DTBTDTS exhibits good stability and possess a wide absorption range and a high extinction coefficient in the visible-near-infrared region. Besides, compared with bithiophene, the trans bithiophene with vinyl group between the two thiophenes has a longer effective conjugation length and a narrower bandgap. However, the introduction of vinyl reduces the solubility of the three compounds, which leads to poor film during device fabrication and low power conversion efficiency(PCE).

Key words: organic solar cell;  small molecule;  donor materials

目录

第一章 绪论 6

1.1 引言 6

1.2 有机太阳能电池的简介 6

1.2.1 有机太阳能电池的发展历程 6

1.2.2 有机太阳能电池的基本原理 8

1.2.3 有机太阳能电池的性能参数 9

1.3 有机太阳能电池的研究现状 11

1.3.1 受体材料 11

1.3.2 聚合物给体材料 12

1.3.3 小分子给体材料 17

1.3.4 小结 22

1.4 课题的提出 23

第二章 基于二噻吩并噻咯的D1-A-D2-A-D1型给体小分子的设计、合成与表征 24

2.1 材料与方法 24 基于二噻吩并噻咯的D1-A-D2-A-D1型给体小分子的合成与性能研究:http://www.chuibin.com/cailiao/lunwen_206441.html