Fairooz Oudeif
Pronouns: She/her
Research Mentor(s): David Kwabi
Co-Presenter:
Research Mentor School/College/Department: Mechanical Engineering / Engineering
Presentation Date: April 20
Presentation Type: Poster
Session: Session 1 – 10am – 10:50am
Room: League Ballroom
Authors: David Kwabi, Sanat Modak, Fairooz Oudeif
Presenter: 47
Abstract
Organic redox-flow batteries are anticipated to be safer, longer-lasting, and cheaper for grid energy storage than state-of-the-art Li-ion systems. These batteries require the use of organic redox-active molecules such as quinones and phenazines, whose physicochemical and electrochemical properties can be tailored via a variety of synthetic strategies. Current studies nevertheless indicate that many of these molecules undergo rapid degradation leading to capacity loss. Therefore, for a given flow battery chemistry, it is important to study and understand the degradation mechanism and its kinetics in order to devise strategies for its mitigation. In this work, we use a combination of electrochemical and spectroscopic techniques to discern the kinetics of quinone decomposition via nucleophilic attack (Michael addition) by water. Specifically, proton nuclear magnetic resonance (H-NMR) is used to determine the kinetic of Michael addition as a function of redox potential. H-NMR is used to enable inferences about their chemical structures of decay products present in solution over time, and thus their concentrations over time. Our measurements enable us to infer rate constant of Michael addition of water to the oxidized form of 4,5-dihydroxybenzene-1,3-disulfonic acid (BQDS), which is known to result in a lower battery voltage, and thus a progressive loss in the energy density of a flow battery that deploys BQDS as a positive electrolyte. We expect that our work will help to evaluate hypotheses that have been put forward in the literature about the relationship between rate of Michael attack and a quinone’s reduction potential Work cited: Preger, Y., Gerken, J. B., Biswas, S., Anson, C. W., Johnson, M. R., Root, T. W., & Stahl, S. S. (2018). Quinone-Mediated Electrochemical O2 Reduction Accessing High Power Density with an Off-Electrode Co-N/C Catalyst. Joule, 2(12), 2722–2731. https://doi.org/10.1016/j.joule.2018.09.010 Tabor, D. P., Gómez-Bombarelli, R., Tong, L., Gordon, R. G., Aziz, M. J., & Aspuru-Guzik, A. (2019). Mapping the frontiers of quinone stability in aqueous media: implications for organic aqueous redox flow batteries. Journal of Materials Chemistry A, 7(20), 12833–12841. https://doi.org/10.1039/c9ta03219c Yang, Bo, Lena Hoober-Burkhardt, Sankarganesh Krishnamoorthy, Advaith Murali, G. K. Surya Prakash, and S. R. Narayanan. 2016. High-Performance Aqueous Organic Flow Battery with Quinone-Based Redox Couples at Both Electrodes. Journal of the Electrochemical Society 163 (7): A1442–49. https://doi.org/10.1149/2.1371607jes.
Engineering, Interdisciplinary
