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Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
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A Long-Lived Water-Soluble Phenazine Radical Cation
Lu Li1,2, Yihang Su3, Yunlong Ji3
1Key Laboratory of Precise Synthesis of Functional Molecules of Zhejiang Province, Department of Chemistry, School of Science and Research Center for Industries of the Future, Westlake University, 600 Dunyu Road, Hangzhou 310024 Zhejiang, China.
Journal of the American Chemical Society
|February 15, 2023
Summary
We developed a stable, water-soluble organic radical called PSPR for energy storage. This phenazine radical cation demonstrates excellent performance in aqueous organic redox flow batteries, showing minimal capacity fade over 2500 cycles.
Area of Science:
- Organic Chemistry
- Materials Science
- Electrochemistry
Background:
- Long-lived, water-soluble organic radicals are crucial for bioimaging and aqueous energy storage.
- Existing radical species often suffer from instability in aqueous environments.
Purpose of the Study:
- To synthesize and characterize a novel, stable, water-soluble organic radical for advanced applications.
- To evaluate the potential of this radical in aqueous organic redox flow batteries.
Main Methods:
- Synthesis of sodium 3,3'-(phenazine-5,10-diyl)bis(propane-1-sulfonate) (PSPR).
- Experimental and theoretical calculations to assess stability and reactivity.
- Electrochemical characterization and performance testing in a zinc-based redox flow battery.
Main Results:
- PSPR exhibits high water solubility (1.4 M) and stability against dimerization, disproportionation, oxygen, and water.
- The radical shows ambipolar redox activity and magnetic properties.
- A high-performance aqueous organic redox flow battery using PSPR achieved an open-circuit voltage of 1.0 V and maintained performance over 2500 cycles.
Conclusions:
- PSPR is a highly stable and soluble organic radical with potential for bioimaging and energy storage.
- Its robust electrochemical performance makes it a promising candidate for large-scale aqueous organic redox flow batteries.
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