三元体系有机太阳能电池

Organic solar cells use binary system as their active layers, which generally contain one kind of conjugated polymers or small molecules as a donor, and one kind of fullerene derivatives as an acceptor. Ternary organic solar cells use two kinds of donor materials with complimentary properties and one fullerene acceptor as the active layer. The synergistic effect of the two donors will enhance the light absorption properties, and optimize the morphologies of the active layer. As a result, the ternary system has a great potential to further improve the performance of the organic solar cells. This project will carry out the design and construction of ternary systems by Zhixiang Wei’s group, and further study their morphologies in details by Wei Ma’s group. Focusing on the ternary system containing one conjugated small molecule and one conjugated polymer as the donor, and one fullerene derivative as the acceptor, we aim to design and synthesize high performance small molecules and polymers, study the mechanism of synergistic effects of small molecules and polymers, and resolve various key scientific problems for organic solar cells, including the delicate control of the mesophase, high efficient charge transfer and transport and etc. This study aim to increase the power conversion efficiency higher than 12%, which will lay the foundation for the application of organic solar cells.

有机太阳能电池传统上是利用一种共轭聚合物或小分子给体和一种富勒烯受体组成的二元体系作为活性层。三元有机太阳能电池利用性能互补的两种给体材料与富勒烯受体共混作为活性层。两种给体材料的协同效应使活性层吸光增加、形貌优化，具有大幅度提升光伏器件的性能的潜力。本项目由魏志祥课题组开展三元体系的设计和构筑，结合马伟课题组在有机太阳能电池形貌表征方面的丰富经验，拟围绕共轭小分子和聚合物作为给体、富勒烯衍生物作为受体的三元体系，设计合成性能优良的小分子和聚合物材料，系统研究共轭小分子和聚合物的协同效应的机制，解决有机太阳能电池中微相结构精细调控和电荷高效转移传输等关键科学问题，将有机太阳能电池的光电转换效率提升至>12%，为有机太阳能电池的应用奠定基础。

三元有机太阳能电池利用性能互补的两种给体或受体材料的协同效应使活性层吸光增加、形貌优化，具有大幅度提升光伏器件的性能的潜力。本项目合成、筛选了一系列不同给-受体结构的共轭小分子和聚合物材料，获得了一系列高效率的三元材料体系；系统研究了具有相同或不同给-受体结构的共轭小分子和聚合物的相容性，发展了利用非共价相互作用、调控常见三元体系微相分离尺度、纯度和结晶性的新方法；建立了微相分离的参数和器件中电荷的转移和传输关联，提出了构建有效的三元体系提供了设计原则，对三元体系光伏器件和相结构的稳定性进行了系统研究；通过狭缝涂布制备了基于三元体系的柔性大面积有机光伏器件，1平方厘米柔性器件的效率超过12%，并具有很好的耐弯折性能，为柔性有机光伏技术的未来应用奠定了基础。在Nature Communications、Advanced Materials、Joule、Science China Chemistry等国内外期刊共发表标注资助论文47篇，圆满完成了项目的目标。