Creating Anionic Microenvironment Around Single-Atom Fe Sites in Metal-Organic Frameworks for Enhanced Nitrate
Song Chen1, Yunyang Qian2, Ziyong Cheng1
1School of Chemical Engineering and Light Industry, Guangdong University of Technology, Guangzhou, Guangdong, P. R. China.
Angewandte Chemie (International Ed. in English)
|April 4, 2026
Summary
This study introduces SU-102-Fe, a novel catalyst for electrocatalytic nitrate reduction (eNO3RR). It efficiently converts nitrate wastewater into ammonia, overcoming limitations of previous methods.
Area of Science:
- Materials Chemistry
- Electrochemistry
- Catalysis
Background:
- Electrocatalytic nitrate reduction (eNO3RR) is crucial for wastewater treatment and ammonia synthesis.
- Neutral media present challenges due to limited proton availability, hindering reaction kinetics.
Purpose of the Study:
- To develop an efficient catalyst for eNO3RR in neutral conditions.
- To enhance nitrate reduction by improving local proton supply.
Main Methods:
- Functionalization of an anionic metal-organic framework (MOF), SU-102, with atomically dispersed iron (Fe) sites to create SU-102-Fe.
- Electrocatalytic performance testing at -0.7 V vs RHE.
- In situ characterizations to investigate the catalytic mechanism.
Main Results:
- SU-102-Fe achieved a high Faradaic efficiency (FE) of 96.9% and an ammonia production rate of 1.72 mg h⁻¹ mgcat⁻¹.
- The catalyst significantly outperformed commercial Fe2O3 and pristine SU-102.
- Anionic microenvironment around Fe sites facilitated K+•H2O species enrichment and dissociation, enhancing proton supply.
Conclusions:
- The developed SU-102-Fe catalyst effectively addresses the proton limitation in neutral media for eNO3RR.
- The unique anionic MOF structure promotes efficient nitrate-to-ammonia conversion, showing great promise for sustainable applications.
Keywords:
K+•H2Ometal–organic frameworkmicroenvironment modulationnitrate electroreductionsingle atomMore Related Videos
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