二维共轭大分子的设计合成及其在有机太阳能电池中的应用

Organic solar cells have been considered as one of green and effective technology to address today's energy and environment issues. Currently,there is still faced with a lot of bottlenecks in the process.For example,the photo-actived material is a key factor affecting the efficiency of energy conversion.Therefore,in this proposal, we will merge into the advantages of conjugated small organic molecules and conjugated polymer photovoltaic materials by design of two-dimensional conjugated unit mudule.Firstly, we will develope well-defined, monodisperse conjugated two-dimensional D-A type macromolecules(the range of molecular weight is from ca. 1000 to ca.40000) for electronic donor or acceptor materials and the efficient synthesized methodology through high efficient C-H bond activated arylation coupling reaction. The electron acceptor materials with the similar backbone structures as donor materials are otained by enhancing the intensity of electron withdrawing substituents on the constructed module. Secondly,we will obtain two-dimensional conjugated photo-actived materials system with the complementary absorption spectrum and a high absorption coefficient,matched energy-level, high carrier mobility and investigate performance of non-fullerene organic solar cells. Thirdly, we will in-depth study on the relationship of the chemical structure, molecular size, energy level, micro-phase separation morphology of the thin films and the photoelectric conversion performance on solution-processed organic solar cells.The results of current study are expected to provide design principles and synthesized strategies of monodisperse,high molecular sized two-dimensional conjugated D-A type macromolecules as donor and acceptor materials for solution processed bulk heterojunction organic solar cells.

有机太阳能电池被认为是解决当前的能源和环境问题最有效的途径之一。目前其实用化过程还面临很多瓶颈，其中材料是影响能量转换效率的关键要素。本项目拟将有机小分子和聚合物光伏材料的优势相结合，从二维共轭单元模块的设计入手，利用高效的C-H键活化芳基化偶联反应，发展结构规整、单分散的二维共轭的D-A型大分子电子给受体材料（分子量从1000到40000左右）和相应的高效合成方法学。骨架类似的电子受体材料是通过增强给体大分子材料构筑模块上取代基吸电子能力来获得。建立吸收光谱互补且高吸收系数，能级匹配、高载流子迁移率的新型材料体系，并研究基于二维共轭大分子给受体材料非富勒烯型有机太阳能电池的器件性能。深入探讨材料化学结构、分子尺寸、能级位置、微相分离形貌以及光电转换性能之间的内在关联。在此基础上总结出用于溶液加工体异质结有机太阳能电池的大分子尺寸二维共轭大分子给受材料的设计原则合成策略。

有机太阳能电池被认为是解决当前的能源和环境问题最有效的途径之一。目前其实用化过程还面临很多瓶颈，其中材料是影响能量转换效率的关键要素。在本项目中以“单分散有机共轭大分子的合成及其在有机太阳能电池中的应用”为研究中心，在单分散共轭的D-A型宽带隙大分子电子给体材料和窄带隙稠环大分子电子受体材料合成和光伏器件性能方面做了深入系统的研究。得到了材料化学结构、分子尺寸和分子量渐变、能级位置、微相分离形貌以及光电转换性能之间的内在构效关系，总结出用于有机太阳能电池的大分子尺寸共轭大分子给受材料的结构设计策略，取得了一系列有特色的科研成果。发展基于烷基侧链的IDT/双氟代苯并噻二唑的单分散多氟代共轭大分子光伏给体并获得高填充因子(0.78)和9.4%的高效率，是宽带隙单分散给体/PC71BM体系最高值之一，并在三元共混器件中获得14.0%的效率。发展基于苯并二硒吩/硒吩[3,2-b]并噻吩核心的非富勒烯单分散稠环分子光伏受体。这类受体材料与聚合物二元电池获得13.7%的效率，是目前基于单氯取代苯基氰基茚酮为端基的非富勒烯受体材料的二元有机太阳能电池效率的最高值之一。目前为止发表通讯/第一作者SCI论文27篇(含1篇Joule, 1篇J.Am.Chem.Soc.和2篇Adv.Funct.Mater.)，其中4篇为ESI高被引论文(单篇最高引用近100次)。另还有5篇高质量文章在撰写中。项目执行期内，共培养4名博士研究生和13名硕士研究生。