RUI-CHE: Development of Organometallic Complexes for the Next-Generation of Non-Aqueous Redox Flow Batteries

With the support of the Chemical Synthesis program in the Division of Chemistry, Emmanuelle Despagnet-Ayoub of Occidental College is studying new redox active materials for energy storage. Renewable power sources derived from solar energy are promising and environmentally friendly solutions for generating electric power. However, their intermittent behavior does not align with the typical energy demand.

Consequently, more efficient energy storage devices need to be developed. Redox flow batteries are a promising energy storage technology. However, prior redox-flow technologies have considerable challenges meeting the performance requirements for grid storage applications due to their low energy density.

This project, carried out primarily by talented undergraduates, aims to find solutions to overcome these limitations. The research will be carried out synergistically with other projects promoting diversity in STEM fields at Occidental College, such as the COSMOS (Creating Opportunities in Science and Mathematics for Occidental Students, S-STEM grant) and the REAP (Research Early Access Program, Sherman Fairchild grant) programs.

Emmanuelle Despagnet-Ayoub of Occidental College is developing new redox active materials for high energy density redox flow batteries. Indeed, the practical energy density of current redox flow batteries is typically low (10s of Wh/L) due to the use of aqueous solutions with narrow potential windows and redox couples with limited solubility. Development of organometallic complexes with a high solubility in organic solvents and tunable formal potentials will help advance the field.

The PI has recently reported a strategy to anodically shift the formal potential of metal redox couples by outer-sphere coordination of Lewis acids. This concept will be further probed with a variety of complex frameworks and Lewis acids, in order to develop a relationship map between ligand framework-Lewis acid and their electrochemical properties.

The project will ultimately lead to more exciting systems involving multiple electron processes at the molecular and macromolecular levels, and the development of symmetric flow batteries with non-innocent ligands and semi-solid flow batteries with immobilized redox active species. This research project will provide research and training opportunities to undergraduates in the fields of organometallic synthesis and electrochemistry within the larger context of flow batteries and energy storage.

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.