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Extended electrochemical windows made accessible by room temperature ionic liquid/organic solvent electrolyte systems
Marisa C Buzzeo1, Christopher Hardacre, Richard G Compton
1Physical and Theoretical Chemistry Laboratory, University of Oxford, South Parks Road, Oxford, OX1 3QZ, United Kingdom.
Summary
Ionic liquids in acetonitrile solutions offer wider electrochemical windows compared to traditional electrolytes. A specific phosphate-based ionic liquid enhances the anodic window due to its stable anionic component.
Area of Science:
- Electrochemistry
- Materials Science
Background:
- Electrochemical windows are crucial for electrolyte performance in electrochemical devices.
- Acetonitrile solutions are common electrolytes, often paired with tetrabutylammonium perchlorate.
- Ionic liquids offer potential advantages due to their unique properties.
Purpose of the Study:
- To evaluate the electrochemical windows of acetonitrile solutions containing various ionic liquids.
- To compare ionic liquid electrolytes with the standard tetrabutylammonium perchlorate system.
- To identify ionic liquids that enhance electrochemical performance.
Main Methods:
- Cyclic voltammetry was employed to determine electrochemical windows.
- Gold and platinum microelectrodes were used for measurements.
- Experiments were conducted in acetonitrile solutions with 0.1 M ionic liquid doping and neat ionic liquids.
Main Results:
- Several ionic liquids were tested as supporting electrolytes in acetonitrile.
- A trifluorotris(pentafluoroethyl)phosphate-based ionic liquid demonstrated a wider anodic window.
- This wider window is attributed to the high stability of the ionic liquid's anionic component.
Conclusions:
- Phosphate-based ionic liquids can significantly expand the anodic electrochemical window in acetonitrile.
- The stability of the ionic liquid's anion is key to achieving enhanced performance.
- These findings suggest potential for improved electrolyte formulations in electrochemical applications.
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