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Updated: Jun 9, 2025
09:50
Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
12.7K
Localized High-Concentration Electrolyte in Li-Mediated Nitrogen Reduction for Ammonia Synthesis
Hyeju Yun1,2, Chaeeun Lim1,2, Minjun Kwon3
1Surface Chemistry Laboratory of Electronic Materials (SCHEMA), Department of Chemical Engineering, Pohang University of Science and Technology (POSTECH), Pohang, 37673, South Korea.
Advanced Materials (Deerfield Beach, Fla.)
|October 22, 2024
Summary
Localized high-concentration electrolytes (LHCEs) enable efficient ammonia synthesis via lithium-mediated nitrogen reduction reaction (Li-NRR). This approach forms a stable solid electrolyte interphase (SEI) in low-concentration electrolytes, overcoming limitations of traditional methods.
Area of Science:
- Electrochemistry and Materials Science
- Green Chemistry and Sustainable Energy
Background:
- The lithium-mediated nitrogen reduction reaction (Li-NRR) offers a sustainable alternative to the Haber-Bosch process for ammonia synthesis.
- The solid electrolyte interphase (SEI) is critical for Li-NRR performance, influencing reactant diffusion and side reactions.
- SEI properties are linked to Li+ ion solvation, which can be tuned via electrolyte engineering, but high-concentration electrolytes (HCEs) present practical challenges.
Purpose of the Study:
- To introduce a localized high-concentration electrolyte (LHCE) strategy for Li-NRR.
- To enable anion-derived SEI formation in low-concentration electrolytes (LCEs) for improved Li-NRR efficiency and stability.
- To investigate the role of antisolvents in tailoring SEI properties and enhancing electrochemical performance.
Main Methods:
- Development and application of LHCEs using antisolvents to modify Li+ ion solvation.
- Electrochemical characterization, including ammonia Faradaic efficiency measurements.
- Systematic calculations and experimental analyses to elucidate SEI formation mechanisms and electrolyte properties.
Main Results:
- The antisolvent 1,1,2,2-tetrafluoroethyl-2,2,3,3-tetrafluoropropyl ether (TTE) in LHCE achieved a record ammonia Faradaic efficiency of 73.6 ± 2.5%.
- LHCE significantly outperformed both LCE (34.3 ± 2.8%) and HCE (56.0 ± 2.8%) in ammonia production.
- LHCE facilitated the formation of a thin, inorganic SEI with anion-rich solvation structures, low viscosity, and high N2 solubility.
Conclusions:
- LHCE is a highly effective electrolyte engineering strategy for enhancing Li-NRR efficiency and stability.
- The developed LHCE system overcomes the mass transfer, viscosity, and cost limitations associated with traditional HCEs.
- This approach paves the way for more practical and sustainable ammonia synthesis via electrochemical methods.
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