Substrate-Enhanced reactivity of pristine graphene in cycloaddition reactions

麻省大学洛厄尔分校的闫明迪教授和劳伦斯·沃尔夫教授在化学系大分子、超分子和纳米化学（MSN）项目的支持下，开发了实验和计算指导的方法，以提高原始石墨烯（一种无缺陷的单层二维碳材料）的反应性。理论与实验的结合提供了对导致加速发现的反应的全面、基本的理解。研究结果对该材料的实际应用有直接影响，该材料表现出非凡的机械、电学和热性能。原始石墨烯具有影响许多重要技术应用的潜力，如显示屏、纳米电子学、太阳能电池等。原始石墨烯比其他形式的石墨烯具有优势，其他形式的石墨烯要么被氧化，要么含有许多缺陷。所使用的计算建模技术被纳入了为本科生和研究生开设的新的计算化学课程。参与该项目的学生通过个性化发展计划接受研究规划和评估方面的培训。招募了代表性不足的本科生和女性本科生参与该项目。该项目旨在扩大原始石墨烯的化学空间。具体来说，通过实验和计算研究了底物和界面对原始石墨烯在环加成反应中的反应活性的影响。原始石墨烯是通过化学气相沉积或转移在不同的表面上制造的。以全氟芳基叠氮化物的（2+1）环加成反应为重点，进行了环加成反应，并对产物进行了表征。该研究旨在阐明石墨烯的反应性与其支撑衬底界面之间的关系。原始石墨烯在其他环加成反应中的反应活性也是本研究的主题。通过现代反应性模型的发展和应用，利用密度泛函理论建立了原始石墨烯的环加成底物/反应性关系的理论基础。原始石墨烯在化学上是相当惰性的，因为它的共轭π电子在整个二维网络上的离域产生了很大的共振稳定性。克服这些固有的反应性挑战提供了在原始石墨烯中引入定义良好的功能的能力。其他好处包括调节石墨烯的溶解度和带隙，并使其集成到高性能复合材料和器件中。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。

Professors Mingdi Yan and Lawrence Wolf of the University of Massachusetts Lowell are supported by the Macromolecular, Supramolecular, and Nanochemistry (MSN) Program of the Division of Chemistry to develop experimental and computationally guided approaches to enhance the reactivity of pristine graphene (a defect-free single layer, two-dimensional carbon material). The integration of theory with experiment provides a comprehensive, fundamental understanding of the reactions leading to the acceleration of discovery. The results have a direct impact on the practical utilization of this material, which exhibit extraordinary mechanical, electrical and thermal properties. Pristine graphene has the potential to impact many technologically important applications, such as in display screens, nanoelectronics, solar cells, and various others. Pristine graphene offers advantages over other forms of graphene, which are either oxidized or contain many defects. The computational modeling techniques used are incorporated in the curriculum of new computational chemistry courses offered to both undergraduate and graduate students. The students involved in the project receive training in research planning and evaluation through individualized development plans. Under-represented and female undergraduate students are recruited to participate in the project. This project aims to expand the chemical space of pristine graphene. Specifically, the impacts of substrate and interface on the reactivity of pristine graphene in cycloaddition reactions is investigated both experimentally and computationally. Pristine graphene is fabricated on different surfaces by chemical vapor deposition or by transfer. Cycloaddition reactions, with initial focus on the (2+1) cycloaddition with perfluoroaryl azides, are carried out and the products are characterized. The study aims to shed light on the relationship between the reactivity of graphene and its supporting substrate interface. The reactivity of pristine graphene in other cycloaddition reactions is also a subject of this investigation. The theoretical underpinnings of the cycloaddition substrate/reactivity relationships with pristine graphene is established using density functional theory through the development and application of modern reactivity models. Pristine graphene is fairly inert chemically due to the large resonance stabilization resulting from the delocalization of its conjugated pi electrons over the entire two-dimensional network. Overcoming these inherent reactivity challenges offers the ability to introduce into pristine graphene well-defined functionalities. Other benefits include modulating graphene solubility and bandgap, and enabling its integration into high performance composite materials and devices.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.