Promoting the Intermediates Hydrogenation for Urea Electrosynthesis Over an “Active Hydrogen Pump” Catalyst

Abstract

Abstract Electrocatalytic coupling of CO 2 and NO 3 − offers a sustainable approach for urea production. However, the limited supply of active hydrogen (*H) hinders the formation of the key carbon‐ and nitrogen‐containing intermediates, thus impeding the selective C─N coupling. Herein, we developed copper molybdate (Cu 3 Mo 2 O 9 ) nanorods, which could serve as “active hydrogen pump” catalysts by regulating the water dissociation and hydrogen adsorption. Such electrocatalyst would guarantee a steady *H supply for intermediates hydrogenation, hence boosting the generation of *CO and *NH 2 intermediates for selective C‒N coupling and urea production. In a CO 2 ‐saturated 0.1 M KNO 3 solution, Cu 3 Mo 2 O 9 achieved a maximum urea yield rate of 177 mmol h −1  g −1 with a urea‐producing FE of 40% in a flow cell configuration, outperforming most reported electrocatalysts. This study underscores the crucial role of *H, which may guide the exploration of advanced catalysts for expediting the sustainable synthesis of indispensable chemicals requiring rapid intermediates hydrogenation.