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Updated: Sep 13, 2025
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Ion-Exchange Membranes for the Fabrication of Reverse Electrodialysis Device
Published on: July 20, 2021
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Anion-Exchange-Membrane Electrolysis with Alkali-Free Water Feed
Mohsin Muhyuddin1, Carlo Santoro1, Luigi Osmieri2
1Electrocatalysis and Bioelectrocatalysis Laboratory (EBLab), Department of Materials Science, University of Milano-Bicocca, U5, Via Roberto Cozzi 55, 20125 Milan (MI), Italy.
Chemical Reviews
|August 1, 2025
Summary
Anion-exchange-membrane water electrolyzers (AEM-WEs) can use pure water, reducing costs and improving sustainability. This review explores AEM-WEs with pure water feeds, addressing challenges and proposing solutions for efficient hydrogen production.
Area of Science:
- Green energy technologies
- Electrochemical engineering
- Sustainable hydrogen production
Background:
- Anion-exchange-membrane water electrolyzers (AEM-WEs) offer advantages like precious metal-free electrocatalysts and fluorine-free membranes.
- Current AEM-WEs require alkaline electrolytes for optimal performance, increasing complexity and cost.
- Alkali-free operation is desirable for reduced costs and extended device lifetime.
Purpose of the Study:
- To provide a foundational understanding of AEM-WEs operating with pure water.
- To discuss the effects of natural water feeds, such as seawater, on AEM-WE performance.
- To identify challenges and propose mitigation strategies for pure-water-fed AEM-WEs.
Main Methods:
- Review of thermodynamic and kinetic processes in AEM-WEs.
- Detailed examination of materials and components (membranes, electrocatalysts, transport layers, bipolar plates).
- Analysis of the influence of electrolyte composition and alkali-free feeds on device performance and degradation.
Main Results:
- Pure water feed in AEM-WEs presents unique challenges related to component degradation.
- Specific issues arise from alkali/electrolyte-free operation impacting membrane-electrode assemblies and other components.
- Strategies for mitigating degradation in pure-water-fed AEM-WEs are discussed.
Conclusions:
- Operating AEM-WEs with pure water is a key goal for cost-effective and sustainable hydrogen production.
- Understanding and addressing component degradation is crucial for the successful implementation of alkali-free AEM-WEs.
- Further research into materials and configurations is needed to optimize pure-water-fed AEM-WE technology.
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