A Novel Flow Battery Using Quinoxaline Derivatives As Redox Couple
Quinoxaline is a promising active material for flow batteries due to its low molecular weight, high solubility and ability to transfer two electrons per pyrazine ring. In this study, quinoxaline-derivatives were studied, and the reduction potentials including hydroxyquinoxaline and methylquinoxaline are calculated with DFT, while solvation free energies calculated by COSMO model. A better reversibility as well as rapid kinetics have been observed. The most of the derivatives are highly soluble in aqueous or non-aqueous solutions and the reduction potentials are relatively low (~-0.3V) indicate that can be combined with the Br2/Br- couple, which would show high energy efficiency. Electrochemical properties of quinoxaline-derivatives with various concentration, different additions, in different solvents will be tested which would involving Cyclic Voltammetry (CV), Electrochemical Impedance Spectroscopy (EIS), Rotating Disk Electrode and Rotating Ring-Disk Electrode (RDE and RRDE). The battery performance will be tested employing quinoxaline-derivatives and Br2/Br-as cathode and anode redox couples, respectively.
Key words:flow battery, redox couple, quinoxaline
Acknowledgment:This work was supported by the National High Technology R&D Program of China (2012AA053401)
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