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Published on: August 16, 2018
Physical properties of proton conducting membranes based on a protic ionic liquid
Anna Martinelli1, Aleksandar Matic, Per Jacobsson
1Department of Applied Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden. annamart@fy.chalmers.se
The Journal of Physical Chemistry. B
|October 12, 2007
Summary
Proton conducting polymer membranes show improved stability but reduced conductivity as polymer content increases. This is due to the physical confinement of the protic ionic liquid within the polymer matrix.
Area of Science:
- Materials Science
- Electrochemistry
- Polymer Science
Background:
- Proton conducting polymer membranes are crucial for electrochemical devices.
- Ionic liquids (ILs) offer potential as proton conductors.
- Understanding the interplay between ILs and polymer matrices is key for membrane development.
Purpose of the Study:
- To investigate the physical properties of proton conducting polymer membranes based on protic ionic liquids.
- To analyze the impact of ionic liquid/polymer ratio and temperature on membrane properties.
- To elucidate the relationship between membrane morphology, ionic liquid confinement, and overall performance.
Main Methods:
- Fabrication of proton conducting polymer membranes with varying ionic liquid (IL) content.
- Characterization of thermomechanical properties, including melting point and glass transition temperature.
- Measurement of ionic conductivity as a function of IL/polymer ratio and temperature.
Main Results:
- Increased polymer content enhanced thermomechanical stability but decreased ionic conductivity.
- The observed conductivity decrease exceeded simple dilution effects, suggesting morphological and interaction-based contributions.
- Changes in glass transition temperature and conductivity's temperature dependence indicated physical confinement of the IL within the polymer.
Conclusions:
- The physical confinement of the protic ionic liquid within the polymer matrix significantly impacts membrane properties.
- Optimizing the IL/polymer ratio is critical to balance mechanical stability and ionic conductivity.
- Further research into membrane morphology and IL-polymer interactions is warranted for advanced proton conducting membranes.
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