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Updated: May 22, 2025

Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
Electrocatalytic CN Coupling: Advances in Urea Synthesis and Opportunities for Alternative Products
Parker Ballard-Kyle1, Isabel Hsieh1, Huiyuan Zhu1
1Department of Chemistry, University of Virginia, 409 McCormick Rd, Charlottesville, VA, 22904, USA.
Abstract:
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 CO2 emissions. Electrocatalytic urea synthesis under ambient conditions via CN coupling from CO2 and 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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