Seo Joonsik, Kantha Chandra, Joung Joonyoung F, Park Sungnam, Jelinek Raz, Kim Jong-Man
Department of Chemical Engineering, Hanyang University, Seoul, 04763, Korea.
Institute of Nano Science and Technology, Hanyang University, Seoul, 04763, Korea.
Small. 2019 May;15(19):e1901342. doi: 10.1002/smll.201901342. Epub 2019 Apr 10.
Because of their unique structural and optical properties, 1D perylene diimide (PDI) derivatives have gained attention for use in optoelectronic devices. However, PDI-containing self-assembled supramolecular systems often are of limited use because they have supramolecular architectures that are held together by weak noncovalent π-π stacking, hydrogen bonding, and hydrophobic interactions. As a result, they are intrinsically unstable under solution-processing conditions. To overcome this limitation, a polydiacetylene (PDA)-based strategy is developed to construct a solvent-resistant and stable PDI assembly. For this purpose, first the monomer PDI-BisDA is generated, in which two polymerizable diacetylene (DA) units are covalently linked to a PDI core. Importantly, 254 nm UV irradiation of self-assembled PDI-BisDA nanofibers forms solvent-resistant and stable PDI-PDA fibers. Owing to the presence of PDA, the generated polymer fibers display an increased photocurrent. In addition, the existence of PDA and PDI moieties in the fiber leads to the occurrence of switchable on-off fluorescence resonance energy transfer (FRET) between the PDI and reversibly thermochromic PDA chromophores.
由于其一维苝二酰亚胺（PDI）衍生物独特的结构和光学性质，它们在光电器件中的应用受到了关注。然而，含PDI的自组装超分子体系的用途往往有限，因为它们具有由弱非共价π-π堆积、氢键和疏水相互作用维系在一起的超分子结构。因此，它们在溶液加工条件下本质上是不稳定的。为克服这一限制，开发了一种基于聚二乙炔（PDA）的策略来构建耐溶剂且稳定的PDI组装体。为此，首先生成单体PDI-BisDA，其中两个可聚合的二乙炔（DA）单元共价连接到一个PDI核心上。重要的是，对自组装的PDI-BisDA纳米纤维进行254 nm紫外线照射可形成耐溶剂且稳定的PDI-PDA纤维。由于PDA的存在，生成的聚合物纤维显示出增强的光电流。此外，纤维中PDA和PDI部分的存在导致在PDI与可逆热致变色的PDA发色团之间发生可切换的开-关荧光共振能量转移（FRET）。
