Cu-Doped CeO2 Supported by MXene Nanosheets for Enhanced Electrosynthesis of Urea from Carbon Dioxide and Nitrate

Electrocatalytic synthesizing of urea through C-N coupling of CO2 and NO3− under ambient conditions is a possible solution for the problem of energy consumption in commercial urea production. Herein, we report a Cu-doped CeO2 catalyst anchored on delaminated MXene two-dimensional surface. The Cu-CeO2/MXene catalyst achieves the co-reduction of CO2 and NO3− to synthesize urea, obtaining a urea yield rate of 505.1 μg·h−1·mgcat.−1 with a Faradic efficiency (FE) of 6.3% at −0.8 V versus reversible hydrogen electrode (vs. RHE). Theoretical calculations further demonstrate that Cu doping is capable of enhancing the activity of Cu-Ce sites and promoting C-N coupling and protonation reactions.