Corresponding Author

Yong-gang WANG(ygwang@fudan.edu.cn)


Hydrogen has been considered as a promising alternative to unsustainable fossil fuels because of its high calorific value, clean and abundant resources. Water electrolysis combined with renewable energy is regarded as the best way for hydrogen production, which will become the foundation of future hydrogen economy. For the past few years, many efforts have been employed to develop the cheap and high-performance catalyst for hydrogen evolution reaction and oxygen evolution reaction. However,the coupled hydrogen and oxygen evolution and the use of the expensive membrane have greatly restricted the flexibility of the conventional water electrolysis, and hindered the utilization of renewable energy. Recently, our group has introduced the battery-electrode as a solid-state redox mediator to separate the hydrogen and oxygen productions during water electrolysis in space and time, providing a flexible and membrane-free architecture for water splitting. This decoupled architecture also facilitates the conversion of renewable energy to hydrogen. This review highlights the research progresses, and analyzes the advantages and challenges to this new architecture.

Graphical Abstract


battery-electrode, water electrolysis, decoupled, renewable energy

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