面向D-A型共轭高分子的含B←N键拉电子单元

Electron donating-accepting (D-A) conjugated polymers have attracted much attention for their characters of tunable energy levels, broad absorption bands and high carrier mobility, which show highly potential applications in organic/polymer solar cells (OSC) and organic/polymer field-effect transistors (OFET). However, the development of these conjugated polymers is quite difficult due to less reported electron-accepting units. In this project, we aim to design novel B←N bridged electron-accepting units with further functionality, and use them to develop B←N embedded D-A conjugated polymers with highly tunable LUMO/HOMO energy levels. Moreover, applying these polymers into OSC devices as electron donor or acceptor materials will be performed. The most interesting points of this project are its novel molecular design strategies of electron-accepting units, as well as new functional B←N-containing conjugated polymers. This wok will not only bring a novel concept for polymer chemistry, but also provide functional materials for organic/polymer opto-electronic device.

“推—拉电子（D-A）”型共轭高分子具有能级结构可调、可实现宽吸收光谱和高载流子迁移率的特点，是高性能有机/高分子太阳能电池（OSC）和有机/高分子场效应晶体管（OFET）所需要的核心材料。鉴于已有的拉电子单元的种类很少，限制了D-A型共轭高分子的设计，本项目旨在开发含B←N键的可功能化拉电子单元，发展含B←N键的D-A型共轭高分子，实现对这类高分子LUMO/HOMO能级的连续精细调节，探索其作为高分子太阳能电池给体材料或受体材料的应用。其独特之处在于，在已有两类拉电子单元（噻二唑类和酰胺键类）之外，发展出一系列含B←N键的拉电子单元，从而可以构建全新结构共轭高分子。该研究一方面将为共轭高分子化学带来新思路，另一方面将为有机/高分子光电材料与器件领域提供材料基础。

项目组以推—拉电子（D-A）型共轭高分子为研究主题，开发了数个基于硼氮配位键（B←N）的可功能化拉电子单元，发展出硼氮配位键n-型高分子半导体材料，在有机光电材料领域形成了特色研究方向。在该项目支持下，发表学术论文19篇，包括Angew. Chem. Int. Ed. 3篇，Adv. Mater. 1篇, Chem. Sci. 1篇, Macromolecules 3篇等。授权和申请中国发明专利各2项。代表性成果包括：（1）开发出含有两个B←N键的双硼氮桥联联吡啶单元，实现了共轭高分子LUMO能级的连续分布和精细调控，获得了能级结构可调、高电子迁移率的n-型高分子半导体材料；（2）构建了含有一个B←N键的硼氮桥联噻吩联噻唑单元，发展出一系列无定型n-型高分子半导体材料，揭示了这类无定型高分子作为受体材料与多种高分子给体材料共混的共混机制；（3）开发出基于B←N键的梯形结构稠环分子，发展出具有近红外吸收性质的硼氮配位键共轭高分子。