Steering the Glycerol Electro-Reforming Selectivity via Cation-Intermediate Interactions
Jianxiang Wu1, Jili Li1, Yefei Li1,2
1Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Fudan University, Shanghai, 200438, P. R. China.
Angewandte Chemie (International Ed. in English)
|December 27, 2021
Summary
Lithium cations steer glycerol electro-reforming towards formate production by stabilizing aldehyde intermediates. This discovery enhances sustainable hydrogen and formate generation through optimized electrode-electrolyte interfaces.
Area of Science:
- Electrochemistry
- Renewable Energy
- Catalysis
Background:
- Sustainable hydrogen (H2) production is crucial for clean energy.
- Electro-reforming of biomass offers a promising alternative.
- Understanding reaction mechanisms is key to optimizing efficiency.
Purpose of the Study:
- To investigate the unconventional cation effect on glycerol electro-reforming.
- To elucidate the mechanism of concurrent formate and H2 production.
- To enhance selectivity towards formate generation.
Main Methods:
- Glycerol electro-reforming experiments.
- Product analysis and transient kinetics.
- Crown ether trapping, in situ IRRAS, and DFT calculations.
Main Results:
- Cations at the anode interact with glycerol oxidation intermediates.
- Li+ cations stabilize aldehyde intermediates, favoring C-C cleavage.
- Maximal formate efficiency reached 81.3% in LiOH at 60 mA cm-2.
Conclusions:
- Cation engineering of the electrode-electrolyte interface is significant for efficient electro-reforming.
- This work provides a new strategy for selective formate production.
- Highlights the importance of understanding interfacial microenvironments in electrocatalysis.
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