Tailored Intermediate Adsorption for Efficient Electrosynthesis of Urea via Co-Reduction of Nitrate and Carbon Dioxide

Electrocatalytic co-reduction of nitrate (NO₃⁻) and carbon dioxide (CO₂) to synthesize urea is expected to be a viable and sustainable replacement for the energy-intensive Haber-Bosch process. The principal hurdles in the synthesis of urea are the inherent inertness of the reactants leading to low coverage of the C─N coupling intermediates, the sluggish kinetics and thermodynamics of the coupling procedure, and the emergence of competing parallel reactions. In this concept, we provide a brief overview of recent advances and involved mechanisms of urea electrosynthesis in terms of tailoring the adsorption behavior of intermediates and reactively coupling intermediates to improve the kinetics and selectivity of C─N coupling. Based on performance data and in situ spectroscopic characterization, the developed strategies focus on enhancing the accessibility of coupling atoms in C/N intermediates while concurrently optimizing active sites. Finally, shortcomings, optimization methods, and opportunities of urea electrosynthesis are summarized with the aim of contributing to the promotion of efficient urea.