Ruiz Constanza, Martín Raúl, Benito Angela, Gutierrez Enrique, Monge M Ángeles, Facchetti Antonio, Termine Roberto, Golemme Attilio, Gómez-Lor Berta
Instituto de Ciencia de Materiales de Madrid, CSIC, Cantoblanco 28049, Madrid, Spain.
School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, Georgia 30332, United States.
ACS Appl Electron Mater. 2024 Jun 11;6(6):4709-4717. doi: 10.1021/acsaelm.4c00693. eCollection 2024 Jun 25.
We report a semiconducting triindole-based discotic liquid crystal () functionalized with six -methylthiophenyl groups at its periphery. While initially a crystalline solid at room temperature, transitions to a columnar hexagonal mesophase upon heating and retains this supramolecular organization upon subsequent cooling, despite having only three flexible alkyl chains attached to the core's nitrogens. The incorporation of methylthio groups effectively hinders tight molecular packing, stabilizing the columnar arrangement of this disk-shaped molecule. Single crystal analysis confirmed the high tendency of this compound to organize into a columnar architecture and the role played by the methylthio groups in reinforcing such structure. The mesomorphic behavior of provides an opportunity for processing from its molten state. Notably, our research reveals significant differences in charge transport depending on the processing method, whether solution drop-casting or melt-based. shows hole mobility values averaging 3 × 10 cm V s when incorporated in diode-type devices from the isotropic melt and annealed at the mesophase temperature, estimated by SCLC (space-charge-limited current) measurements. However, when integrated into solution-processed organic field-effect transistors (OFETs), crystalline exhibits a hole mobility of 3 × 10 cm V s. The observed differences can be attributed to a beneficial supramolecular assembly achieved in the mesophase in spite of its lower order. These results emphasize the material's potential for applications in easy-to-process electronic devices and highlight the potential of methylthio moieties in promoting columnar mesophases.
我们报道了一种基于三吲哚的盘状液晶半导体（），其外围被六个甲基硫苯基官能化。虽然该化合物在室温下最初是结晶固体，但加热时会转变为柱状六方中间相，并且在随后冷却时仍保持这种超分子结构，尽管其核心氮原子上仅连接了三条柔性烷基链。甲硫基的引入有效地阻碍了紧密的分子堆积，稳定了这种盘状分子的柱状排列。单晶分析证实了该化合物具有高度的形成柱状结构的倾向以及甲硫基在强化这种结构中所起的作用。该化合物的介晶行为为从其熔融状态进行加工提供了机会。值得注意的是，我们的研究表明，根据加工方法（溶液滴铸或熔体法）的不同，电荷传输存在显著差异。当从各向同性熔体中掺入二极管型器件并在中间相温度下退火时，通过空间电荷限制电流（SCLC）测量估计，该化合物的空穴迁移率平均为3×10 cm V s。然而，当集成到溶液处理的有机场效应晶体管（OFET）中时，结晶态的该化合物表现出3×10 cm V s的空穴迁移率。观察到的差异可归因于尽管中间相的有序度较低，但仍在其中实现了有益的超分子组装。这些结果强调了该材料在易于加工的电子器件中的应用潜力，并突出了甲硫基部分在促进柱状中间相方面的潜力。
