基于双氧环苯并噻二唑基聚合物的高效全有机太阳能电池研究

High efficient all organic photovoltaic cells are the research focus in the photovoltaic field, the photosensitive active layer materials which absorb the sunlight into the electric energy play a decisive role in the performance of the devices.This project aims at the development of high performance polymer donor materials, designed and synthesized for the first time 6,7-dihydronaphtho[2,3-c][1,2,5]thiadiazole-5,8-dione-based polymers.The molecular backbone has a high degree of coplanarity, which is favorable for charge transport, and thus it can improve the carrier mobility of the devices. By adjusting the side chain groups and so on, the donor polymers have medium or wide optical band gap, which are easy to match with the nonfullerene organic small-molecule acceptors to prepare the high-efficiency devices. Meanwhile, we will study the influence of the different side chain and main chain structures on the active layer morphology and photovoltaic properties of the devices and explore the relationship between molecular structures and properties, and summarize the molecular design basis of high efficient polymer donors. The proposal will use the designed and synthesized non-conjugated organic small-molecule electrolytes to optimize the interface between the active layer and the metal cathode by solution-processed, and then develop the organic solar cells with the efficiencies of 11-13%.

高效全有机太阳能电池是目前光伏领域的研究热点，其光敏活性层材料作为吸收太阳光转换为电能的主体材料对电池性能起着决定性作用。本项目旨在发展高性能的聚合物给体材料，首次设计合成双氧环苯并噻二唑基聚合物。其分子主链具有高的共平面性，利于电荷传输，从而提高电池器件的载流子迁移率。通过调节侧链基团等使其具有中等或宽的光学带隙，易与非富勒烯有机小分子受体材料匹配制备高效率的电池器件。同时，研究其不同侧链和主链结构对活性层形貌和光伏性能的影响，探索分子结构与性能的关系，总结高效聚合物给体材料的分子设计依据。电池器件制备中利用设计合成的可湿法加工的非共轭有机小分子电解质界面材料优化活性层与金属阴极的界面，研发效率11-13%的有机太阳能电池。

本项目围绕高性能给受体材料和有机太阳能电池制备开展了系列研究。通过设计与合成新型小分子给体材料BTEC-2F，实现了全小分子有机太阳能电池13.34%的转换效率。实现了湿法加工的高效率有机太阳能电池的制备，刚性有机太阳能电池效率达到18.5%，柔性有机太阳能电池效率15.9%（有效面积4 mm2），为目前最高效率之一。通过本项目的支助，在Angewandte Chemie International Edition、Advanced. Materials、Journal of Materials Chemistry A等期刊上发表本基金（No. 51773212）资助的SCI论文15篇，申请发明专利5项，获得2018年度浙江省自然科学二等奖，项目负责人2019年度获得国家杰出青年科学基金项目资助等，顺利完成项目目标。