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Electrochemical C–N coupling via the coreduction of CO2and nitrogenous species (N2/NOx) presents a sustainable route to synthesize value‐added C–N compounds under mild conditions. However, competing pathways and mismatched intermediate kinetics hinder the selective formation of products like urea, amines, and amides. Recent advances reveal that rational modulation of the electrochemical microenvironment can effectively steer reaction pathways and stabilize coupling‐relevant intermediates. This review systematically summarizes how microenvironment engineering, originally developed for CO2and NOxreduction reactions, can be leveraged to enhance C–N coupling efficiency and selectivity. The key strategies are categorized into 1) catalyst‐centered design (e.g., ligand coordination, defect engineering, and morphology control), 2) ionic and electrolyte modifications (e.g., cation/pH effects), and 3) dynamic approaches such as pulsed electrolysis. These methods shape local fields, surface coverage, and mass transport properties, ultimately directing reactants toward cross‐coupling over competing routes. By drawing parallels with well‐established CO2RR/NOxRR systems and showcasing emerging examples in C–N coupling, the central role of microenvironment control is highlighted. Finally, a perspectives on strategies to further improve activity, selectivity, and atom economy in future C–N coupling systems are offered.
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This content will become publicly available on April 12, 2026
Electrocatalytic CN Coupling: Advances in Urea Synthesis and Opportunities for Alternative Products
Urea is an essential fertilizer produced through the industrial synthesis of ammonia (NH3) via the Haber–Bosch process, which contributes ≈1.2% of global annual CO2emissions. Electrocatalytic urea synthesis under ambient conditions via CN coupling from CO2and nitrogen species such as nitrate (NO3−), nitrite (NO2−), nitric oxide (NO), and nitrogen gas (N2) has gained interest as a more sustainable route. However, challenges remain due to the unclear reaction pathways for urea formation, competing reactions, and the complexity of the resulting product matrix. This review highlights recent advances in catalyst design, urea quantification, and intermediate identification in the CN coupling reaction for electrocatalytic urea synthesis. Furthermore, this review explores future prospects for industrial CN coupling, considering potential nitrogen and carbon sources and examining alternative CN coupling products, such as amides and amines.
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- Award ID(s):
- 2332802
- PAR ID:
- 10586690
- Publisher / Repository:
- Wiley-VCH
- Date Published:
- Journal Name:
- ChemSusChem
- ISSN:
- 1864-5631
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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