Abstract
Electrochemical characterization indicates that the redox reaction of cyclohexanedione is a proton-coupled electron transfer process with quasi-reversible behavior in acidic media (pH < 3). Among three isomeric compounds (1,2-, 1,3- and 1,4-cyclohexanedione), the reduction of 1,3-cyclohexanedione exhibits the most negative electrode potential (c.a. −0.6 V vs. Ag|AgCl (c.a. −0.4 V vs. NHE)) as well as the widest pH operating range (pH 1–5) for relatively reversible reactions. The resulting electrode potential is the most negative of those to have been reported in neutral/acidic electrolytes. 1,3-cyclohexanedione is subsequently used as the active species in the negative electrode of a parallel plate flow cell, which is charge-discharge cycled at 3.4 mA cm−2for 100 cycles, yielding half-cell coulombic efficiencies of c.a. 99%. The organic molecules derived from this group are observed to have high solubilities (>2 M) and exhibit reduction process with up to 4 electrons transferred.
Original language | English |
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Pages (from-to) | 318-326 |
Number of pages | 9 |
Journal | Applied Energy |
Volume | 197 |
DOIs | |
Publication status | Published - 1 Jan 2017 |
Keywords
- Aqueous flow batteries
- Cyclohexanedione
- Organic flow batteries
- Redox flow batteries
- Soluble
ASJC Scopus subject areas
- Civil and Structural Engineering
- Building and Construction
- General Energy
- Mechanical Engineering
- Management, Monitoring, Policy and Law