Efficient C-N coupling in electrocatalytic urea generation on copper carbonate hydroxide electrocatalysts

Abstract

Urea generation through electrochemical CO2 and NO3− co-reduction reaction (CO2NO3RR) is still limited by either the low selectivity or yield rate of urea. Herein, we report copper carbonate hydroxide (Cu2(OH)2CO3) as an efficient CO2NO3RR electrocatalyst with an impressive urea Faradaic efficiency of 45.2% ± 2.1% and a high yield rate of 1564.5 ± 145.2 μg h−1 mgcat−1. More importantly, H2 evolution is fully inhibited on this electrocatalyst over a wide potential range between −0.3 and −0.8 V versus reversible hydrogen electrode. Our thermodynamic simulation reveals that the first C-N coupling follows a unique pathway on Cu2(OH)2CO3 by combining the two intermediates, *COOH and *NHO. This work demonstrates that high selectivity and yield rate of urea can be simultaneously achieved on simple Cu-based electrocatalysts in CO2NO3RR, and provide guidance for rational design of more advanced catalysts.