Tailoring Functional organic materials through supramolecular chemistry

通过超分子化学定制功能有机材料

• 批准号: RGPIN-2016-06069
• 负责人: Williams, Vance
• 金额: $ 1.82万
• 依托单位: Simon Fraser University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=616085
• 关键词: Tailoring; Functional; organic; materials; through

Our research encompasses the design, synthesis and study of functional organic materials. These efforts can be broadly categorized into two major avenues of inquiry: (a) determining how molecular structure relates to the self-assembly of ordered materials, and (b) the design of new materials whose properties can be altered using external stimuli such as light. An overarching goal of our research is to establish general methods whereby supramolecular interactions can be rationally exploited in the creation of new materials. To this end, we strive to understand how molecules interact with each other and how these interactions can be manipulated using light. Our first broad research theme focuses on the formation of columnar liquid crystal phases by disc-shaped molecules. These phases have been widely targeted as organic semiconducting materials for LEDs, photovoltaics and field effect transistors. Much of their promise stems from their high charge carrier mobilities, their ease of alignment and their ability to self-heal. Our aim is to elucidate the rules that govern the formation of these liquid crystals. We developed a highly modular synthetic approach that facilitates the preparation of families of disc-shaped targets, which allowed us to probe the effects of functional groups, size, and symmetry on phase behavior. Whereas our previous efforts focused on isolating these effects, future studies will tackle the more challenging problem of unraveling how different structural features can either work with or against each other during self-assembly. Understanding this subtle interplay is critical for designing multifunctional materials. We will also examine what happens when the molecular building blocks are flexible rather than rigid. Discotic dimers, composed disc-shaped groups linked by a flexible spacer, can adopt a wide variety of conformations, making it difficult to predict how they will self-assemble. By studying their conformational dynamics in solution, we hope to gain insights into their ability to organize into liquid crystalline materials. Ultimately, these flexible molecules will open new avenues towards creating highly structured materials at the nanoscale. Another major research theme is the use of anthracene photochromism in the design of new materials. We have recently created an efficient photoswitch based on two anthracene groups linked by a flexible spacer; this molecule can be reversibly switched between an open and closed form using different wavelengths of light. In our future studies, we will prepare analogs of this system in order to better understand its photochemical properties, which will also facilitate the creation of new derivatives with improved performance. We will also examine how the large changes in shape and rigidity that accompany this photoswitching can be exploited in the design of photoresponsive materials.

我们的研究包括功能有机材料的设计、合成和研究。这些努力可以大致分为两个主要的研究途径：（a）确定分子结构与有序材料的自组装之间的关系，以及（b）设计可以使用外部刺激（例如光）来改变其特性的新材料。我们研究的首要目标是建立通用方法，在新材料的创造中可以合理地利用超分子相互作用。为此，我们努力了解分子如何相互作用以及如何利用光来操纵这些相互作用。 我们的第一个广泛的研究主题集中于盘状分子形成柱状液晶相。这些相已被广泛用作 LED、光伏和场效应晶体管的有机半导体材料。它们的前景很大程度上源于它们的高载流子迁移率、易于排列以及自我修复的能力。我们的目标是阐明控制这些液晶形成的规则。我们开发了一种高度模块化的合成方法，有助于制备圆盘状靶标家族，这使我们能够探究官能团、尺寸和对称性对相行为的影响。尽管我们之前的努力侧重于隔离这些影响，但未来的研究将解决更具挑战性的问题，即阐明不同的结构特征在自组装过程中如何相互作用或相互对抗。了解这种微妙的相互作用对于设计多功能材料至关重要。 我们还将研究当分子构件是柔性而不是刚性时会发生什么。盘状二聚体是由柔性间隔基连接的盘状基团，可以采用多种构象，因此很难预测它们将如何自组装。通过研究它们在溶液中的构象动力学，我们希望深入了解它们组织成液晶材料的能力。最终，这些柔性分子将为创建纳米级高度结构化材料开辟新途径。 另一个主要研究主题是蒽光致变色在新材料设计中的应用。我们最近创建了一种基于通过柔性间隔物连接的两个蒽基团的高效光电开关；该分子可以使用不同波长的光在开放和闭合形式之间可逆地切换。在未来的研究中，我们将制备该系统的类似物，以更好地了解其光化学性质，这也将有助于创造具有改进性能的新衍生物。我们还将研究如何在光响应材料的设计中利用伴随这种光切换而产生的形状和刚度的巨大变化。