Cavendish Laboratory, University of Cambridge, Cambridge, CB30HE, UK.
Institute for Quantum Electronics, ETH Zürich, 8093, Zurich, Switzerland.
Angew Chem Int Ed Engl. 2023 Mar 13;62(12):e202216729. doi: 10.1002/anie.202216729. Epub 2023 Feb 8.
Organic semiconductors are promising for efficient, printable optoelectronics. However, strong excited-state quenching due to uncontrolled aggregation limits their use in devices. We report on the self-assembly of a supramolecular pseudo-cube formed from six perylene diimides (PDIs). The rigid, shape-persistent cage sets the distance and orientation of the PDIs and suppresses intramolecular rotations and vibrations, leading to non-aggregated, monomer-like properties in solution and the solid state, in contrast to the fast fluorescence quenching in the free ligand. The stabilized excited state and electronic purity in the cage enables the observation of delayed fluorescence due to a bright excited multimer, acting as excited-state reservoir in a rare case of benign inter-chromophore interactions in the cage. We show that self-assembly provides a powerful tool for retaining and controlling the electronic properties of chromophores, and to bring molecular electronics devices within reach.
有机半导体在高效、可打印的光电领域有很大的应用前景。然而，由于无法控制聚集，强烈的激发态猝灭限制了它们在器件中的应用。我们报告了一种由六个苝二酰亚胺（PDI）组成的超分子拟立方的自组装。刚性、形状保持的笼状结构设定了 PDIs 的距离和方向，并抑制了分子内的旋转和振动，导致在溶液和固态中没有聚集，类似于单体的性质，与游离配体中快速的荧光猝灭形成对比。在笼中，稳定的激发态和电子纯度使得观察到延迟荧光成为可能，这是由于明亮的激发多聚体的作用，它在笼中罕见的发色团间相互作用的良性情况下充当激发态储库。我们表明，自组装为保留和控制发色团的电子性质提供了一种强大的工具，并使分子电子器件成为可能。
