Ambient electrosynthesis of urea from carbon dioxide and nitrate over Mo2C nanosheet

Abstract

Electrocatalytic synthesis of urea through CN bond formation, converting carbon dioxide (CO2) and nitrate (NO3–), presents a promising, less energy-intensive alternative to industrial urea production process. In this communication, we report the application of Mo2C nanosheets-decorated carbon sheets (Mo2C/C) as a highly efficient electrocatalyst for facilitating CN coupling in ambient urea electrosynthesis. In CO2-saturated 0.2 mol/L Na2SO4 solution containing 0.05 mol/L NO3–, the Mo2C/C catalyst achieves an impressive urea yield of 579.13 µg h–1 mg–1 with high Faradaic efficiency of 44.80% at –0.5 V versus the reversible hydrogen electrode. Further theoretical calculations reveal that the multiple Mo active sites enhance the formation of *CO and *NH2 intermediates and facilitate their CN coupling. This research propels the use of Mo2C-based electrodes in electrocatalysis and accentuates the capabilities of binary metal-based catalysts in CN coupling reactions.