The Role of Substrate in Accelerating the Reactivity of Graphene in Diels Alder Reactions

在化学系大分子、超分子和纳米化学(MSN)计划的支持下，马萨诸塞大学洛威尔分校的严明迪和劳伦斯·沃尔夫将通过有机合成，特别是Diels-Alder反应，探索单层原始石墨烯纳米碳单分子膜的转化。在具有纳米特征的衬底上，石墨烯表面会产生弯曲扭曲位的局部热点。理论计算将被用来帮助合理设计这些具有曲线特征的石墨烯薄片。原始的石墨烯有可能影响许多重要的技术应用，如在显示屏、纳米电子、太阳能电池等方面，功能化的石墨烯也有类似的但尚未发现的应用。能够以可控的方式使石墨烯具有明确的化学功能是该领域的前沿目标，并有可能提供具有巨大技术应用潜力的新型材料。作为这一研究项目的一部分，研究生和本科生将接受多学科研究方面的培训；还将开发与研究相关的专门课程。此外，不同背景的高中生将获得暑期研究体验，K-12学生将通过科学报告和工作坊演示参与其中。该项目将理论和实验相结合，以提供关于表面曲率如何增强石墨烯的反应性以及哪种底物构型最有利于加速Diels-Alder和其他环加成反应的机理见解。在目标1中，将制备支撑在具有良好表面形貌的金属或绝缘衬底上的单层石墨烯。随后，将进行Diels-Alder反应，并将确定石墨烯的官能化程度，以检验石墨烯的反应性将通过引入表面曲率而增加，并将通过使用金属衬底进一步增加的假设。在目标2中，将发展原子和更大规模的计算方法，包括密度泛函理论、半经验和分子力学方法，并用于研究环加成反应中由表面曲率增强的反应性的起源以及表面曲率的作用和由此产生的扭曲的电子结构对石墨烯的反应性。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program of the Division of Chemistry, Mingdi Yan and Lawrence Wolf from the University of Massachusetts-Lowell will explore the transformation of monolayer pristine graphene nanocarbon monolayer sheets in a controlled fashion through organic synthesis with a particular focus on the Diels-Alder reaction. Local hot spots of curved distorted sites will be created on the graphene surface over nano-featured substrates. Theoretical computations will be used to aid in rationally designing these graphene sheets with curved features. Pristine graphene has the potential to impact many technologically important applications, such as in display screens, nanoelectronics, solar cells, and various others and functionalized graphene has similar and yet to be discovered applications. The ability to functionalize graphene with well-defined chemical functionalities and in a controlled fashion is a frontier goal in the field and has the potential to provide access to novel materials with great potential for technological application. As part and parcel of this research project, graduate and undergraduate students will be trained in multidisciplinary research; specialized courses related to the research will also be developed. Furthermore, high school students of diverse backgrounds will be provided with summer research experience and K-12 students will be engaged through science presentations and workshop demonstrations. This project will integrate theory and experiment to provide mechanistic insights on how surface curvature enhances the reactivity of graphene and which substrate configurations best accelerate Diels-Alder and other cycloaddition reactions. In Aim 1, monolayer graphene supported on a metallic or insulating substrate having well-defined surface topography will be fabricated. Subsequently, Diels-Alder reactions will be carried out, and the extent of graphene functionalization will be determined to test the hypothesis that the reactivity of graphene will increase by introducing surface curvature and will further increase by using a metal substrate. In Aim 2, combined atomistic and larger scale computational methods, including density functional theory, semi-empirical, and molecular mechanics methods, will be developed and used to investigate the origins of the reactivity enhancement by surface curvature and the role of surface curvature and the resulting distorted electronic structure on the reactivity of graphene in cycloaddition reactions.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.