【作者】 田甜； 魏朵； 葛玲玲； 郭荣；

【Author】 Tian Tian;Duo Wei;Lingling Ge;Rong Guo;School of Chemistry and Chemical Engineering,Yangzhou University;

【机构】 扬州大学化学化工学院；

【摘要】 苝二酰亚胺(PDI)是一类有机半导体光电材料,因为具有可见光区域内较高的价电传递速率,以及较高的热、化学和光学稳定性等特性,广泛应用于有机光电器件和生物领域。已有研究表明,通过调节分子间相互作用,如π-π堆积、氢键等,可以调节聚集形态和光电性质。我们设计合成了肌肽N位取代的不对称苝二酰亚胺衍生物(PeC),亲水性肌肽提供了超分子手性来源,同时与苝环的π-π堆积作用协同为自组装行为提供导向驱动力。本文利用圆二、紫外、荧光和透射电子显微镜等多种手段系统地探究了浓度、时间以及溶剂组成等因素对PeC自组装行为的影响。研究表明,PeC在四氢呋喃中,由于其π-π堆积作用随着浓度增大而增强,聚集程度也随之提高。所形成的自组装体具有右手螺旋结构,表明分子手性向超分子手性的转移。随着老化时间延长,PeC手性自组装体逐渐转变为较小的无规的聚集体。通过调控混合溶剂中四氢呋喃和水的体积比,可以实现自组装体的手性反转。更多还原

【Abstract】 Perylene diimides(PDIs) are a class of organic semiconductor optoelectronic materials that are widely used in organic optoelectrical devices and biological field because of high charge transport in the visible region and high thermal, chemical and optical stability. The optoelectrical properties are related to the aggregation morphologies which can be adjusted by tuning intermolecular interactions such as π-π stacking, hydrogen bonding, etc.. We design an asymmetric N-substituted perylene diimide by a dipeptide i.e. L-carnosine(PeC). The hydrophilic carnosine provides a source of supramolecular chirality, while providing synergistic driving force for self-assembly in conjunction with the π-π stacking of the perylene diimide. In the present contribution, the effects of concentration, ageing and solvent composition on the self-assmebly are systematically investigated by methods of UV, CD, Fluorescence, TEM, etc.. Increasing concentration of PeC in tetrahydrofuran leads to enhancing π-π stacking, which consequently results in higher degree of aggregation. The self-assemblies generated adopt a right-handed helical pattern, indicating a translation of molecular chirality into supramolecular helicity. As the ageing time prolongs, the helical PeC aggregates gradually transform into smaller disordered stacked aggregates. The chiral inversion of the self-assemblies can be achieved by adjusting the volume ratio of tetrahydrofuran to water in the mixed solvent.更多还原