Tailoring Organic Molecules for Symmetric Redox Flow Battery Applications and More

氧化还原液流电池（rfb）以溶解的化学物质的形式存储能量，可以可逆地获得或失去电子（分别为还原和氧化），是大规模储能的领先技术，可以实现可再生能源与电网的整合，减少我们对化石燃料的依赖。钒rfb是商业上最先进的系统，但钒的高成本和可持续性问题导致了对替代品的需求。在这一研究领域中，近年来有机材料作为可调和可持续的储能材料的使用获得了越来越多的兴趣。拟议的研究计划旨在通过开发可还原和氧化的独特有机储能材料来推进有机RFB技术。这允许一个简单的“对称”设计，其中一个分子作为正极和负极活性物质，这消除了困扰不对称设计的不可逆容量衰减，并且还可以降低系统成本，因为不需要昂贵的离子交换膜。此外，这里选择的特定材料的目标是它们能够进行双电子还原和双电子氧化，这有效地使RFB的能量存储容量增加了一倍。这项工作的长期目标是利用我们独特的分子设计，为rfb提供商业上可行和可持续的储能材料。该研究项目的第二个方面建立在我们之前资助的探索基金研究的基础上，并针对更基本的问题。我们之前已经开发了一些已知的高度还原的有机分子，并证明了它们在合成中作为均相有机还原剂的应用。在制备这些分子的过程中，我们最近获得了一种独特的吡啶化物中间体参与的光谱证据，我们的目标是对其进行充分表征，包括理论建模以揭示与其稳定性相关的细微差别，并捕获反应以证明其参与。此外，我们将研究双相、离子液体/有机溶剂系统，这些系统应该能够催化涉及我们已经开发的高还原性有机分子的过程。这一进展将大大增加这些试剂的可能性，为更传统的金属还原剂提供令人兴奋的补充。该项目还将为学生提供有吸引力的培训机会，培养他们解决一般问题和批判性思维的能力，以及与化学合成、材料表征相关的特定技能，以及接触尖端储能研究。

Redox flow batteries (RFBs), where energy is stored in the form of dissolved chemical species that can reversibly gain or lose electrons (reduction and oxidation, respectively), are a leading technology for large scale energy storage to enable integration of renewable energy with the grid and reduce our dependence on fossil fuels. Vanadium RFBs are the most commercially advanced systems, but the high cost of vanadium and sustainability concerns have resulted in the need for alternatives. Within this area of research, the use of organic materials as tunable and sustainable energy storage materials has gained increasing interest in recent years. The proposed research program aims to advance organic RFB technology by developing unique organic energy storage materials that can be both reduced and oxidized. This allows for a simple "symmetric" design, where one molecule acts as both positive and negative electrode active species, which eliminates irreversible capacity fade that plagues asymmetric designs, and can also lead to lower costs systems since expensive ion-exchange membranes are not needed. Moreover, the particular materials chosen here are targeted for their ability to undergo two-electron reduction and two-electron oxidation, which effectively doubles the energy storage capacity of the RFB. The long-term goal of this work is to take advantage of our unique molecular designs to enable commercially viable and sustainable energy storage materials for RFBs. A second aspect of the research program builds on our previously funded Discovery Grant research, and targets more fundamental issues. We have previously developed some of the most highly reducing organic molecules known, and demonstrated their application as homogeneous organic reducing agents in synthesis. In preparing these molecules, we have recently acquired spectroscopic evidence for the involvement of a unique pyridinium ylide intermediate, which we aim to characterize fully, including theoretical modelling to uncover nuances related to its stability, and trapping reactions to prove its involvement. Moreover, we will study biphasic, ionic liquid/organic solvent systems that should enable catalytic processes involving the highly reducing organic molecules that we have developed. Such an advance would greatly increase the possibilities for these reagents, which offer exciting complementarity to more traditional metallic reductants. This program will also provide engaging training opportunities for students to develop general problem solving and critical thinking skills, in addition to specific skills related to chemical synthesis, materials characterization, as well as exposure to cutting edge energy storage research.