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Updated: Jun 30, 2026
09:50
Electrochemically and Bioelectrochemically Induced Ammonium Recovery
Published on: January 22, 2015
Interfacial Confinement-Programmed Hydrogen Spillover on Ag/CoNiS Boosts Nitrate-to-Ammonia Electrosynthesis
Fengting Xie1, Xuxin Kang2, Zongtai Li3
1State Key Laboratory of Advanced Fiber Materials, College of Materials Science and Engineering, Donghua University, Shanghai, China.
Advanced Materials (Deerfield Beach, Fla.)
|June 29, 2026
Summary
This study introduces Ag/CoNiS heterostructures for efficient electrochemical ammonia synthesis via nitrate reduction. The novel design optimizes hydrogen transfer, achieving high yields and selectivity under ambient conditions.
Area of Science:
- Electrochemistry
- Materials Science
- Catalysis
Background:
- Electrochemical nitrate reduction (NO3RR) is a sustainable pathway for ammonia (NH3) synthesis.
- Efficiency is limited by kinetic mismatches between water dissociation and nitrate hydrogenation.
Purpose of the Study:
- To design Ag/CoNiS heterostructures for enhanced electrochemical nitrate reduction.
- To regulate hydrogen spillover and improve ammonia synthesis efficiency.
Main Methods:
- Fabrication of Ag/CoNiS heterostructures with controlled Ag loading.
- Electrochemical characterization including in situ Raman, DRT analysis, and isotopic labeling.
- Density functional theory (DFT) calculations to elucidate reaction mechanisms.
Main Results:
- Optimized AgM/CoNiS achieved 22.31 mg h-1 cm-2 NH3 yield with 99.13% Faradaic efficiency.
- Confined Ag-CoNiS interface balanced hydrogen supply and consumption, suppressing hydrogen evolution.
- DFT revealed Ag facilitates nitrate deoxygenation; excessive Ag hinders water activation.
Conclusions:
- Ag/CoNiS heterostructures effectively promote electrochemical nitrate reduction for ammonia synthesis.
- Coupling NO3RR with sulfide oxidation reaction (SOR) enabled a low-voltage electrolyzer (0.70 V) for co-production of ammonia and sulfur.
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