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Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
Published on: July 20, 2021
Ionic resistance and permselectivity tradeoffs in anion exchange membranes
Geoffrey M Geise1, Michael A Hickner, Bruce E Logan
1Materials Science and Engineering, The Pennsylvania State University , University Park, Pennsylvania 16802, United States.
ACS Applied Materials & Interfaces
|September 18, 2013
Summary
Developing advanced anion exchange membranes (AEMs) is crucial for salinity gradient energy technologies. Optimizing water content in AEMs balances ionic resistance and permselectivity, enhancing energy conversion efficiency.
Area of Science:
- Materials Science
- Electrochemistry
- Renewable Energy
Background:
- Salinity gradient energy technologies offer a noncarbon energy source.
- Anion exchange membranes (AEMs) are critical components in these systems.
- Improved AEMs are essential for optimizing salinity gradient energy conversion.
Purpose of the Study:
- To investigate structure-property relationships in AEMs for salinity gradient energy.
- To develop structure-property relationships between transport properties, water content, and fixed charge concentration.
- To optimize AEMs for enhanced performance in salinity gradient energy applications.
Main Methods:
- Synthesized and characterized quaternary ammonium-functionalized AEMs.
- Measured ionic resistance and permselectivity of AEMs.
- Correlated ion transport properties with water content and fixed charge concentration.
Main Results:
- Ionic resistance decreased by over 3 orders of magnitude with increasing water content.
- Permselectivity decreased by 6% as water content increased.
- A trade-off was observed between permselectivity and ionic resistance, influenced by water content.
Conclusions:
- Water content is a key factor in tuning AEM transport properties.
- Optimizing water volume fraction is crucial for balancing ionic resistance and permselectivity.
- Understanding these relationships is vital for designing high-performance AEMs for salinity gradient energy.
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