共轭金属聚合物受体材料的合成及其在全聚合物太阳电池的应用

All-polymer solar cells (all-PSCs) possess many specific advantages, including the easily tunable absorption and energetic properties, stable film morphology upon long-term operation and superior mechanical properties, which make them promising for industrialization. However, as the key materials for photoactive layer, the lack of high-performance polymer acceptors seriously hindered the further improvement of overall device performance for all-PSCs. In this proposal, we introduce the concept of metallated conjugated polymers into the structural design of polymer acceptor and develop a series of aromatic diimide based D-A conjugated metallated polymers. From the viewpoint of molecular design, naphthalene diimide, naphthodithiophene diimide and perylene diimide on the backbone can ensure resulting polymers suitable energy level and excellent electron mobility; the introduction of thiophene bridges can effectively switch the absorption spectrum and energy level; the supramolecular interaction between metal atoms on the backbone can induce more ordered self-assembled micro-structure and further promote the electron-transporting property. Via these original intentions, the electron-transporting property and aggregation state of resulting metallated conjugated polymers can be controlled and high-performance all-PSCs can be expected after further device optimization.

全聚合物太阳电池的吸收与能级可调控、形貌稳定、机械性能好等优势，使其极具产业化前景。但其光活性层的核心材料—高效聚合物受体材料的缺乏阻碍了全聚合物太阳电池性能的进一步提升。本申请拟将共轭金属聚合物的设计思路引入到聚合物电子受体设计上，开发以芳香酰亚胺为受体单元的D-A型共轭金属聚合物受体材料。在结构设计上，主链萘并二酰亚胺、萘并二噻吩二酰亚胺、苝二酰亚胺等单元保证了聚合物具有合适的能级与高电子迁移率；噻吩桥的设计能够有效地调节聚合物的光谱吸收与能级结构；主链金属-金属之间的超分子作用能够诱导形成更有序的自组装结构，进而提升材料的电子传输性能。通过上述的结构设计，有望调控目标聚合物的电子传输性能以及聚集态结构，获得高效的聚合物受体材料，得到高性能的全聚合物太阳电池。

全聚合物太阳电池因其独特的光/热稳定性以及机械韧性，是目前最有希望实用化的光伏技术。其中，作为活性层组分之一的聚合物受体是全聚合物性能的主要决定因素之一。本项目围绕高效全聚合物太阳电池这个大主题，原创性地将Y型非富勒烯小分子受体聚合化，构建了一系列高摩尔消光系数，近红外吸收特性的聚合物受体，并首次将全聚合物太阳电池效率提升至14%水平；同时、通过进一步的聚合物受体、给体结构的协同调控获得高效的聚合物给、受体材料并分别制备了效率为15.8%（1 cm2效率为14.4%）的氯仿加工以及效率为14.4%的非卤溶剂甲基四氢呋喃加工的全聚合物太阳电池器件。这些工作极大地提升了全聚合物太阳电池的效率并为设计新型聚合物材料提供了指导。