Development of New Organic Electronic and Optoelectronic Materials

发光材料在传感、生物成像、声学和发光技术等领域有着重要的应用。功能荧光团的开发是这些前沿研究领域的核心。在前人研究的基础上，我们提出了基于创新的分子设计和合成的新型有机发光材料的研究。第一类材料称为AIE活性互穿网络(IPN)水凝胶。AIE是“聚集诱导排放”的缩写。AIE荧光团在分子溶解时是不发射的，但在聚集时是高度发射的。IPN水凝胶是两种或两种以上相互交织的水凝胶聚合物的共混物，在机械稳定性、高吸附性能和对外界刺激的敏感响应方面显示出显著的优势。在我们的研究中，我们将合成各种化学键合到IPN水凝胶骨架上的AIE荧光团。AIE荧光团作为“节点”与水凝胶网络进行交联，并有望在各种外界刺激下显示出多种多样的荧光性质。建议的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。要研究的第二类荧光团称为TADF荧光团。TADF指的是“热激活延迟荧光”。TADF荧光团由于具有长寿命、延迟荧光和高内量子效率等独特的优点，近年来引起了人们的极大关注。TADF材料作为下一代有机电致发光器件(OLED)、生物成像和光催化材料已被广泛研究。我们建议的研究将以基于芘的纯有机荧光团为目标，这些荧光团将被合成、表征并优化用于发光和荧光成像应用。除了各种新的荧光材料外，我们还将研究一类前所未有的功能化“碳纳米带”(CNBS)。碳纳米管具有迷人的分子结构和电子性质，类似于它们更大的类似物--碳纳米管。CNBS的概念早在1954年就被提出，但直到最近三年才被成功合成。为了对这一具有挑战性但快速发展的领域做出贡献，我们建议构建一种新型的功能化CNBS，使用溴取代的奎诺二甲烷(QMD)作为关键的构建成分。我们的合成策略是通过高效的环加成反应将两个弯曲的QMD嵌入的纳米带连接起来形成一条带。这种碳纳米管的一个关键优点是，各种氧化还原活性官能团可以很容易地安装在其边缘，从而实现氧化还原可控性和超分子自组装性能。我们的研究将探索碳纳米管及其相关纳米碳材料的基本性质和应用。

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.