Efficient Electroreduction of Nitrate into Ammonia at Ultralow Concentrations Via an Enrichment Effect
Zhimin Song1,2, Yan Liu1, Yongzhi Zhong1
1Hefei National Research Center for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, P. R. China.
Abstract:
The electroreduction of nitrate (NO3 - ) pollutants to ammonia (NH3 ) offers an alternative approach for both wastewater treatment and NH3 synthesis. Numerous electrocatalysts have been reported for the electroreduction of NO3 - to NH3 , but most of them demonstrate poor performance at ultralow NO3 - concentrations. In this study, a Cu-based catalyst for electroreduction of NO3 - at ultralow concentrations is developed by encapsulating Cu nanoparticles in a porous carbon framework (Cu@C). At -0.3 V vs reversible hydrogen electrode (RHE), Cu@C achieves Faradaic efficiency for NH3 of 72.0% with 1 × 10-3 m NO3 - , which is 3.6 times higher than that of Cu nanoparticles. Notably, at -0.9 V vs RHE, the yield rate of NH3 for Cu@C is 469.5 µg h-1 cm-2 , which is the highest value reported for electrocatalysts with 1 × 10-3 m NO3 - . An investigation of the mechanism reveals that NO3 - can be concentrated owing to the enrichment effect of the porous carbon framework in Cu@C, thereby facilitating the mass transfer of NO3 - for efficient electroreduction into NH3 at ultralow concentrations.
Related Concept Videos
Inorganic Nitrogen Assimilation
Metabolism of Chemolithotrophs
Preparation of Amines: Reduction of Oximes and Nitro Compounds
Though catalytic hydrogenation can reduce nitrobenzenes, the reduction is nonselective in the presence of other functional groups. For instance, if nitrobenzene contains an aldehyde group,...
2° Amines to N-Nitrosamines: Reaction with NaNO2
Electrodeposition
Electrodeposition can...
Preparation of Amines: Reductive Amination of Aldehydes and Ketones


