CAS: Bidirectional Molecular Catalysts to Control Dinitrogen Reduction and Ammonia Oxidation

在化学系化学催化项目的支持下，蒙大拿州立大学的迈克尔·莫克正在研究储存能量的方法，方法是开发金属催化剂，将空气中发现的氮气转化为燃料，如氨。了解氮和氨之间的转化提供了一个潜在的无碳燃料循环，以相互转换化学能和电能。该项目将专注于使用铬、铁和镍等廉价金属合成新的催化剂。根据设计，这些催化剂的新颖行为将用于生成氨和将氨转化为氮。该项目将制定通过使用化学试剂、电力和/或光能与金属催化剂一起移除和连接氢原子来实现氮和氨的相互转化的战略。此外，模拟小组将接待来自蒙大拿州部落学院的美国原住民本科生在实验室工作，学习合成化学和催化，并获得动手实验室技能。向美洲原住民学生提供化学实践经验将有助于增加未被充分代表的少数族裔参与化学，并将有助于加强蒙大拿州和美国的技术队伍。该项目将使地区中小学开展外联活动，使学生参与有关可再生能源和新能源技术的主题。地区学校的科学推广活动将使学生就对环境和社会产生积极影响的可再生能源和新能源技术的主题展开讨论。在该项目下，蒙大拿州立大学的迈克尔·莫克教授正在研究分子催化系统，以开发基于氮的循环，以存储和利用N-H键中的能量。使用铬和铁的催化剂将被设计用于氮气(N2)和氨(NH3)的相互转化。该项目可能会导致对同一催化剂上用于氮气还原和氨氧化的H原子转移反应有更好的机理理解。因此，评估了两个具有挑战性的多质子、多电子反应的微观可逆性的概念，这些反应涉及N-N和N-H键的形成和断开。通过使用化学试剂、电催化条件和/或光能，将实现将H原子输送到N_2和从NH3配体中去除H原子的常见策略。该项目将测量热力学N-H键强度，并对金属-NxHy中间体进行表征，以推进催化剂设计。拟议的工作将使用镍基平台，以了解在形成氮素的过程中的均质N-H键断裂和N-N耦合步骤。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 the support of the Chemical Catalysis program in the Division of Chemistry, Michael Mock of Montana State University is studying ways to store energy by developing metal catalysts to convert dinitrogen gas found in air to a fuel such as ammonia. Understanding the transformation between nitrogen and ammonia offers a potential carbon-free fuel cycle to interconvert chemical and electrical energy. The project will focus on the synthesis of new catalysts using inexpensive metals such as chromium, iron, and nickel. By design, the novel behavior of these catalysts will be used to both form ammonia and convert ammonia to nitrogen. The project will establish strategies for the interconversion of nitrogen and ammonia by removing and attaching hydrogen atoms using chemical reagents, electricity, and/or light energy in conjunction with the metal catalysts. Additionally, the Mock group will host Native American undergraduate students from Montana Tribal Colleges to work in the laboratory to learn about synthetic chemistry and catalysis, and to acquire hands-on laboratory skills. Providing hands-on experience in chemistry to Native American students will serve to increase the involvement of underrepresented minorities in chemistry and will contribute to strengthening the technical workforce in Montana and in the United States. This project will enable outreach activities at area primary and secondary schools to engage students on the topics of renewable forms of energy and new energy technologies. Science outreach activities at area schools will engage students on the topics of renewable forms of energy and new energy technologies that have a positive impact on the environment and society. Under this project, Professor Michael Mock of Montana State University is studying molecular catalytic systems to develop a nitrogen-based cycle to store and utilize energy in N–H bonds. Catalysts using chromium and iron will be designed for the interconversion of dinitrogen (N2) and ammonia (NH3). The project will likely lead to a better mechanistic understanding of H-atom transfer reactions of the same catalyst for both N2 reduction and NH3 oxidation. hence assessing the concept of microscopic reversibility for two challenging multi-proton, multi-electron reactions involving making and breaking N–N and N–H bonds. A common strategy of delivery of H-atoms to N2 and the removal of H-atoms from NH3 ligands will be accomplished by using chemical reagents, electrocatalytic conditions, and/or light energy. The project will measure thermodynamic N–H bond strengths and characterize metal-NxHy intermediates to advance catalyst design. The proposed work will use Ni-based platforms for understanding homolytic N–H bond cleavage and N–N coupling steps en route to dinitrogen formation.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.