In situ evolution of electrocatalysts for enhanced electrochemical nitrate reduction under realistic conditions

Chen，Yingkai1,2; Luo，Jiayu2; Ling，Li2; Zhan，Zhengshuo2; Liu，Jiutan3; Gao，Zongjun3; Lam，Jason Chun Ho4; Feng，Chunhua1; Lei，Yang2

2025

10.1016/j.ese.2024.100492

Environmental Science and Ecotechnology   影响因子和分区

2666-4984

Electrochemical nitrate reduction to ammonia (ENRA) is gaining attention for its potential in water remediation and sustainable ammonia production, offering a greener alternative to the energy-intensive Haber-Bosch process. Current research on ENRA is dedicated to enhancing ammonia selectively and productivity with sophisticated catalysts. However, the performance of ENRA and the change of catalytic activity in more complicated solutions (i.e., nitrate-polluted groundwater) are poorly understood. Here we first explored the influence of Ca and bicarbonate on ENRA using commercial cathodes. We found that the catalytic activity of used Ni or Cu foam cathodes significantly outperforms their pristine ones due to the in situ evolution of new catalytic species on used cathodes during ENRA. In contrast, the nitrate conversion performance with nonactive Ti or Sn cathode is less affected by Ca or bicarbonate because of their original poor activity. In addition, the coexistence of Ca and bicarbonate inhibits nitrate conversion by forming scales (CaCO) on the in situ-formed active sites. Likewise, ENRA is prone to fast performance deterioration in treating actual groundwater over continuous flow operation due to the presence of hardness ions and possible organic substances that quickly block the active sites toward nitrate reduction. Our work suggests that more work is required to ensure the long-term stability of ENRA in treating natural nitrate-polluted water bodies and to leverage the environmental relevance of ENRA in more realistic conditions.

Ammonium Cathodic corrosion Groundwater Hardness ions In situ activation

英语

通讯

2-s2.0-85204876670

Scopus

1.School of Environment and Energy,South China University of Technology,Guangzhou,510006,China
2.Shenzhen Key Laboratory of Precision Measurement and Early Warning Technology for Urban Environmental Health Risks,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
3.College of Earth Science and Engineering,Shandong University of Science and Technology,Qingdao,Shandong,266590,China
4.School of Energy and Environment and State Key Laboratory,of Marine Pollution,City University of Hong Kong,Hong Kong,999077,China

Chen，Yingkai,Luo，Jiayu,Ling，Li,et al. In situ evolution of electrocatalysts for enhanced electrochemical nitrate reduction under realistic conditions[J]. Environmental Science and Ecotechnology,2025,23.

Chen，Yingkai.,Luo，Jiayu.,Ling，Li.,Zhan，Zhengshuo.,Liu，Jiutan.,...&Lei，Yang.(2025).In situ evolution of electrocatalysts for enhanced electrochemical nitrate reduction under realistic conditions.Environmental Science and Ecotechnology,23.

Chen，Yingkai,et al."In situ evolution of electrocatalysts for enhanced electrochemical nitrate reduction under realistic conditions".Environmental Science and Ecotechnology 23(2025).