Self-assembly of highly ordered conjugated polymer aggregates with long-range energy transfer
Self-assembly of highly ordered conjugated polymer aggregates with long-range energy transfer
复制标题
DOI：
10.1038/nmat3127
复制
发表时间：
2011-12-01
期刊：
影响因子：
41.2
通讯作者：
Barbara, Paul F.
中科院分区：
文献类型：
--
作者：
Vogelsang, Jan;Adachi, Takuji;Barbara, Paul F.
共轭聚合物 (CP) 在有机电子器件（例如发光二极管和太阳能电池）中的应用很大程度上取决于这些材料中电子能量传输的性质 (1-5)。单分子光谱通过分子细节揭示了它们的基本特性(6-14)，最近的报告表明，单个 CP 链中的能量传输可以延伸长达 75 nm 的超长距离（参考文献 13,15,16）。一个重要的问题是，当 CP 链聚集成整齐的固体时，这些特性是否能够持续 (2)。在这里，我们证明了由数十个聚合物链组成的聚集体中的电子能量传输发生在与单链相似的距离尺度上。最近开发的对溶剂蒸气退火的分子水平理解使我们能够开发出一种控制 CP 团聚过程的技术 (17)。体积至少为 45,000 nm(3)（分子量约为 21 MDa）的聚集体保持高度有序的形态并显示出明显的荧光闪烁行为，表明实质上是长程能量传输。我们的研究结果提供了一个新的视角，通过它可以观察单个 CP 链的有序性及其形态和光电特性的演变，这最终将使得改进的 CP 器件的合理设计成为可能。
Applications of conjugated polymers (CP) in organic electronic devices such as light-emitting diodes and solar cells depend critically on the nature of electronic energy transport in these materials(1-5). Single-molecule spectroscopy has revealed their fundamental properties with molecular detail(6-14), and recent reports suggest that energy transport in single CP chains can extend over extraordinarily long distances of up to 75 nm (refs 13,15,16). An important question arises as to whether these characteristics are sustained when CP chains agglomerate into a neat solid(2). Here, we demonstrate that the electronic energy transport in aggregates composed of tens of polymer chains takes place on a similar distance scale as that in single chains. A recently developed molecular-level understanding of solvent vapour annealing has allowed us to develop a technique to control the CP agglomeration process(17). Aggregates with volumes of at least 45,000 nm(3) (molecular weight approximate to 21 MDa) maintain a highly ordered morphology and show pronounced fluorescence blinking behaviour, indicative of substantially long-range energy transport. Our findings provide a new lens through which the ordering of single CP chains and the evolution of their morphological and optoelectronic properties can be observed, which will ultimately enable the rational design of improved CP-based devices.