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Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
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Simultaneously Enhancing the Redox Potential and Stability of Multi-Redox Organic Catholytes by Incorporating
Yichao Yan1,2, Sophia G Robinson3,2, Thomas P Vaid1,2
1Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, United States.
Journal of the American Chemical Society
|August 13, 2021
Summary
New organic catholytes using diaminocyclopropenium (DAC) substituents were developed for nonaqueous redox flow batteries. These DAC-modified molecules enable higher voltages and stable cycling, advancing energy storage solutions.
Area of Science:
- Electrochemistry
- Materials Science
- Energy Storage
Background:
- Nonaqueous redox flow batteries require stable organic catholytes with high redox potentials.
- Phenazine and phenothiazine cores offer moderate redox potentials but limited reversibility.
Purpose of the Study:
- To develop novel organic catholytes with enhanced redox potentials and stability.
- To investigate the effect of diaminocyclopropenium (DAC) substituents on phenazine and phenothiazine redox properties.
Main Methods:
- Synthesis of phenazine and phenothiazine derivatives functionalized with DAC substituents.
- Electrochemical characterization using cyclic voltammetry.
- Testing in two-electron nonaqueous redox flow battery configurations.
Main Results:
- DAC substituents increased redox potentials by ~300 mV and improved reversibility.
- The phenothiazine derivative exhibited reversible oxidation at 1.20 V vs Fc/Fc+.
- Redox flow batteries achieved voltages up to 2.0 V with no detectable crossover over 250 cycles.
Conclusions:
- Diaminocyclopropenium-functionalized phenazines and phenothiazines are promising high-potential, stable organic catholytes.
- The DAC group's electron-withdrawing and resonance-stabilizing effects are key to performance.
- These materials demonstrate potential for efficient and durable nonaqueous redox flow batteries.
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