Development of New Organic Electronic and Optoelectronic Materials

发光材料在传感、生物成像、治疗诊断学和发光技术中具有重要的应用。功能性荧光团的开发是这些前沿研究领域的核心。基于我们以前的研究，我们建议研究新的有机发光材料的基础上创新的分子设计和合成。第一类材料被称为AIE活性互穿网络（IPN）水凝胶。AIE代表“聚集诱导排放”。AIE荧光团在分子溶解时不发射，但在聚集时高度发射。IPN水凝胶是两种或更多种水凝胶聚合物彼此交织的共混物，其在机械稳定性、高吸附性能和对外部刺激的敏感响应性方面显示出显著的优点。在我们的研究中，我们将合成各种AIE荧光团化学键合到IPN水凝胶的框架。AIE荧光团充当与水凝胶网络交联的“节点”，并且预期响应于各种外部刺激而显示通用的荧光性质。所提出的AIE活性IPN水凝胶将被开发成用于环境传感、生物成像和其他荧光应用的“智能”荧光材料。待研究的第二类荧光团被称为TADF荧光团。TADF是指“热激活延迟荧光”。TADF荧光团由于具有长延迟荧光寿命和高内量子效率的独特优势，近年来引起了人们的极大关注。TADF材料已被广泛探索作为下一代有机发光器件（OLED）以及生物成像和生物成像的发射器。我们提出的研究将针对芘基纯有机荧光团，将合成，表征，然后优化发光和荧光成像应用。除了各种新的荧光团，我们还将研究一类前所未有的功能化“碳纳米带”（CNB）。CNB具有迷人的分子结构和电子性质，类似于它们的更大的类似物-碳纳米管。CNB的概念早在1954年就被提出，但直到最近三年才成功地合成。为了对这一具有挑战性但快速发展的领域做出贡献，我们建议使用溴取代的醌二甲烷（QMD）作为关键的构建组分来构建一种新型的官能化CNBs。我们的合成策略是通过有效的环加成反应连接两个弯曲的QMD嵌入纳米带形成带。这种CNB的一个关键优点是，各种氧化还原活性官能团可以很容易地安装在它们的边缘，带来氧化还原可控性和超分子自组装性能。本研究将探讨CNBs及相关奈米碳材料的基本性质与应用。

Luminescent materials have important applications in sensing, bioimaging, theranostics, and light-emitting technologies. Development of functional fluorophores is at the heart of these cutting-edge research fields. Built upon our previous studies, we propose to investigate new organic luminescent materials based on innovative molecular design and synthesis. The first class of materials are called AIE-active interpenetrating network (IPN) hydrogels. AIE stands for "aggregation-induced emission". An AIE fluorophore is non-emissive when molecularly dissolved, but highly emissive upon aggregation. IPN hydrogels are blends of two or more hydrogel polymers interlaced with one another, which show significant advantages in terms of mechanical stability, high adsorbent performance, and sensitive responsiveness to external stimuli. In our studies, we will synthesize various AIE fluorophores chemically bonded to the frameworks of IPN hydrogels. The AIE fluorophores act as "nodes" to cross-link with the hydrogel networks, and are expected to display versatile fluorescence properties in response to various external stimuli. The proposed AIE-active IPN hydrogels will be developed into "intelligent" fluorescent materials for environmental sensing, bioimaging, and other fluorescence applications. The second class of fluorophores to be investigated are called TADF fluorophores. TADF refers to "thermally activated delayed fluorescence". TADF fluorophores have attracted enormous attention in recent years owing to their unique advantages of long-lived delayed fluorescence and high internal quantum efficiency. TADF materials have been popularly explored as next-generation emitters for organic light-emitting devices (OLEDs), as well as bioimaging and photocatalysis. Our proposed research will target pyrene-based purely organic fluorophores, which will be synthesized, characterized and then optimized for light-emitting and fluorescence imaging applications. Apart from various new flurophores, we will also investigate an unprecedented class of functionalized "carbon nanobelts" (CNBs). CNBs possess fascinating molecular structures and electronic properties, akin to their larger analogues - carbon nanotubes. CNBs were conceptually proposed as early as 1954, but have only been successfully synthesized in the past three years. To contribute to this challenging but quickly growing field, we propose to construct a new type of functionalized CNBs, using bromine-substituted quinodimethane (QMD) as a key building component. Our synthetic strategy is to connect two curved QMD-embedded nanostrips to form a belt via efficient cycloaddition reactions. A key advantage of such CNBs is that various redox-active functional groups can be readily installed on their edges to bring about redox controllability and supramolecular self-assembling properties. Fundamental properties and applications of the CNBs and related nanocarbon materials will be explored in our studies.