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Updated: Jan 13, 2026
10:00
Hydrogen Production and Utilization in a Membrane Reactor
Published on: March 10, 2023
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Membrane-Free Direct Seawater Electrolysis via Redox Mediator for H2 Production
AJing Song1, Siyuan Mei1, Xin Jin1
1State Key Laboratory of Advanced Fiber Materials, College of Materials Science and Engineering, Donghua University, Shanghai, 201620, China.
Angewandte Chemie (International Ed. in English)
|October 29, 2025
Summary
This study introduces a novel decoupled seawater direct electrolysis system using a TQBQ-COF redox mediator. It enables membrane-free, desalination-free hydrogen production from seawater, offering a cost-effective and scalable solution.
Area of Science:
- Electrochemistry
- Materials Science
- Sustainable Energy
Background:
- Acidic seawater electrolysis is a promising route for sustainable hydrogen production.
- Current methods face challenges like membrane use, complex pretreatment, and intermittent energy integration.
Purpose of the Study:
- To develop a membrane- and desalination-free seawater electrolysis system.
- To enable flexible integration with intermittent renewable energy sources.
- To reduce the cost of hydrogen production from seawater.
Main Methods:
- Construction of a decoupled seawater direct electrolysis (DSDE) system.
- Utilization of TQBQ-COF (Covalent Organic Framework) as a solid-state redox mediator.
- Coupling TQBQ-COF with a Ru-modified catalyst (COF-Ru) for anode and cathode decoupling.
Main Results:
- The DSDE system operates without membranes or desalination.
- TQBQ-COF demonstrates excellent electrochemical performance in both deionized and seawater, unaffected by common ions.
- The system achieves high-purity H2 and Cl2 production with flexible renewable energy integration.
- A hydrogen production cost of $2.5 per kg H2 was achieved.
Conclusions:
- The DSDE system provides a simplified, robust, and scalable approach for practical seawater electrolysis.
- This technology overcomes key limitations of previous seawater electrolysis methods.
- It presents a viable pathway for cost-effective and sustainable hydrogen generation.
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