Light-Induced Electron-Rich Gold Directs Nitrate Reduction to Dinitrogen
Yuwei Diao1, Guangyu Huang2, Yaru Luo3
1Guangdong Provincial Key Laboratory of Chemical Measurement and Emergency Test Technology, Institute of Analysis, Guangdong Academy of Sciences (China National Analytical Center), Guangzhou, Guangdong, China.
Angewandte Chemie (International Ed. in English)
|August 5, 2026
Summary
Researchers developed an electron-rich gold catalyst (ER-Au) that efficiently converts nitrate to nitrogen gas (N₂). This breakthrough in electrocatalytic nitrate reduction reaction (NO₃RR) offers a selective pathway for nitrate purification.
Area of Science:
- Electrochemistry
- Materials Science
- Environmental Chemistry
Background:
- Electrocatalytic nitrate reduction reaction (NO₃RR) is crucial for controlled nitrate conversion.
- Achieving selective conversion to inert nitrogen gas (N₂) is challenging, with a tendency to form soluble reactive nitrogen species.
Purpose of the Study:
- To establish operating-state electron enrichment as a design principle for directing NO₃RR towards N₂.
- To construct and investigate a Cu-induced electronically reconfigured Au (ER-Au) interface for selective nitrate reduction.
Main Methods:
- Electrochemical in situ interfacial characterization.
- Theoretical calculations.
- Product analysis and isotope-labeling experiments.
Main Results:
- The ER-Au interface enters an electron-rich state under illumination, transforming *NO intermediates into N-N coupling configurations.
- ER-Au achieved 90.84% Faradaic efficiency for converting nitrate to N₂ at pH = 1.
- Stable operation for 100 hours was maintained under illuminated acidic NO₃RR conditions.
Conclusions:
- Operating-state electron enrichment is a key mechanism and design principle for endpoint-selective NO₃RR.
- The ER-Au catalyst demonstrates competitive performance for N₂ production in nitrate reduction.
- This work provides a selective route for nitrate purification via electrocatalysis.
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