Structure–property relationships in multifunctional thieno(bis)imide-based semiconductors with different sized and shaped N-alkyl ends
作者:Manuela Melucci、Margherita Durso、Cristian Bettini、Massimo Gazzano、Lucia Maini、Stefano Toffanin、Susanna Cavallini、Massimiliano Cavallini、Denis Gentili、Viviana Biondo、Gianluca Generali、Federico Gallino、Raffaella Capelli、Michele Muccini
DOI:10.1039/c3tc32538e
日期:——
The relationships between the molecular structure, packing modalities, charge mobility and light emission in organic thin films is a highly debated and controversial issue, with both fundamental and technological implications in the field of organic optoelectronics. Thieno(bis)imide (TBI) based molecular semiconductors provide an interesting combination of good processability, tunable self-assembly, ambipolar charge transport and electroluminescence, and are therefore an ideal test base for fundamental studies on the structureâproperty correlation in multifunctional molecular systems. Herein, we introduce a new class of thieno(bis)imide quaterthiophenes having alkyl side chains of different shapes (linear, cyclic, branched) and lengths (C1âC8). We found that contrarily to what is generally observed in most molecular semiconductors, the length of the alkyl substituent does not affect the optical, self-assembly and charge transport properties of TBI materials. However, different electroluminescence powers are observed by increasing the alkyl side, this suggesting a potential tool for the selective modulation of TBI functionalities. A deep experimental and theoretical investigation on this new family of TBI materials is provided.
有机薄膜中分子结构、排列方式、电荷迁移与光发射之间的关系是一个备受争议且引发广泛讨论的问题,对有机光电领域具有重要的基础和技术意义。基于噻吩(双)酰亚胺(TBI)的分子半导体兼具良好的加工性、可调节的自组装、双极电荷运输和电致发光,因此成为研究多功能分子系统结构-性能关联的理想基础。在此,我们介绍了一类新的噻吩(双)酰亚胺四硫苯类分子,具有不同形状(线性、环状、支链)和长度(C1–C8)的烷基侧链。我们发现,与大多数分子半导体的一般观察相反,烷基取代基的长度并未影响TBI材料的光学、自组装和电荷运输特性。然而,在增大烷基侧链时观察到了不同的电致发光强度,这表明它可能成为选择性调节TBI功能的一种有效工具。我们对这一新的TBI材料家族进行了深入的实验和理论研究。