Research Initiation Award - Beyond Traditional Dynamic Linkages: Reinforcing Chemical Stability and Complexity in Next-generation Covalent Organic Frameworks

研究启动奖为传统黑人学院和大学的初级和中期职业教师提供支持，他们正在建立新的研究项目或重新指导和重建现有的研究项目。期望该奖项有助于提高教师的研究能力和效率，改善所在机构的研究和教学，并使本科生参与研究经验。克拉克亚特兰大大学获得的奖项有可能在几个领域扩大影响。该研究旨在开发和表征在固体化学中具有重要意义的新型晶体多孔材料。该研究将为本科生探索前沿材料科学并与国家实验室的研究人员合作提供一个多学科平台。拟议的工作旨在开发下一代共价有机框架（COFs），以避免对传统动态键（如硼基键和氮基键）的共同依赖。COFs是完全由轻质有机元素组成的二维和三维晶体多孔材料。由于其独特的结构特征，如高结晶度、超低密度、大表面积、多用途合成和可预先设计的结构，COFs在过去十年中一直处于多孔材料化学的前沿，并在广泛的领域引起了极大的关注。然而，固有的化学不稳定性和结构复杂性不足阻碍了COFs的充分开发。为此，本研究旨在利用具有有限可逆性的反应，即亲核芳香取代和醛醇缩合，开发超越传统动态键的下一代COFs。通过常规溶剂热法和机械化学法制备了一系列尚未发现的芳基醚连接的COFs和未取代的sp2碳共轭COFs。除了实验合成，这项工作将通过多管齐下的方法揭示新的COF形成的潜在机制，包括模型类似物中的交换反应、计算模拟、动力学研究以及原位表征。最后，本研究将推动下一代COFs在多相催化中的应用，并阐明迄今为止尚不清楚的结构-催化关系，这将指导COFs的合成和增强，用于催化及其他领域。该项目挑战了COF化学的传统，并将生产一系列具有特殊性能的坚固有序的多孔材料，从而为广泛应用开辟了许多可能性，即使在恶劣的操作环境中，这也是当前COF系统的限制。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Research Initiation Awards provide support for junior and mid-career faculty at Historically Black Colleges and Universities who are building new research programs or redirecting and rebuilding existing research programs. It is expected that the award helps to further the faculty member's research capability and effectiveness, improve research and teaching at the home institution, and involves undergraduate students in research experiences. The award to Clark Atlanta University has potential to broaden impacts in several areas. The proposed study intends to develop and characterize new crystalline porous materials that are important in solid state chemistry. The research will provide a multidisciplinary platform for undergraduate students to explore cutting-edge materials science and collaborate with researchers at national laboratories. The proposed work intends to develop next-generation covalent organic frameworks (COFs) that obviate the common reliance upon traditional dynamic linkages such as boron and nitrogen-based linkages. COFs are 2D and 3D crystalline porous materials entirely composed of lightweight organic elements. Due to their unique structural features such as high crystallinity, ultralow density, large surface areas, versatile synthesis, and predesignable structures, COFs have been at the forefront of porous material chemistry in the past decade and garnered enormous attention in widespread areas. However, the inherent chemical instability and inadequate structural complexity are hindering the fullest exploration of COFs. To this end, the work aims to develop the next-generation COFs beyond traditional dynamic linkages by using reactions with limited reversibility, i.e., nucleophilic aromatic substitution and aldol condensation. A series of as-yet-undiscovered aryl ether-linked COFs and unsubstituted sp2 carbon-conjugated COFs will be produced via conventional solvothermal and mechanochemical synthesis. Besides experimental synthesis, the work will unveil the underlying mechanism of new COF formation through multipronged approaches, including exchange reactions in model analogs, computational simulation, and kinetic studies coupled with in situ characterizations. Lastly, the research will advance the use of next-generation COFs in heterogeneous catalysis and elucidate hitherto poorly understood structure-catalysis correlations, which will guide the synthesis and enhancement of COFs for catalysis and beyond. This project challenges the convention of COF chemistry and will produce a series of robust well-ordered porous materials with peculiar properties, thus opening numerous possibilities in widespread applications even in harsh operating environments, which are off-limits of current COF systems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.