Proton-Coupled Electron Transfer: The Engine of Energy Conversion and Storage

Area of Science:

• Energy conversion science
• Catalysis
• Sustainable chemistry

Background:

• Proton-coupled electron transfer (PCET) is fundamental to energy conversion in both chemical and biological processes.
• PCET enables critical reactions such as water splitting, carbon fixation, and nitrogen fixation.

Purpose of the Study:

• To describe four energy systems based on PCET: Artificial Leaf, Bionic Leaf-C, Bionic Leaf-N, and Coordination Chemistry Flow Battery (CCFB).
• To highlight the distinct PCET coupling requirements for different energy systems to optimize efficiency and minimize energy loss.

Main Methods:

• The study describes the design principles and applications of four PCET-based energy systems.
• It analyzes the necessity of strong vs. decoupled PCET for specific applications.

Main Results:

• Artificial Leaf, Bionic Leaf-C, and Bionic Leaf-N require strong PCET coupling for high energy efficiency.
• The CCFB necessitates complete decoupling of electron and proton transfer to prevent energy-wasting side reactions.

Conclusions:

• Strategic design of PCET is crucial for developing efficient energy solutions.
• These PCET systems are applicable to large-scale grid electricity storage and decentralized energy production for fuel and food, supporting a sustainable biogenic element cycle.