Cu-Mo Dual Sites in Cu-Doped MoSe₂ for Enhanced Electrosynthesis of Urea.

Abstract

The quest for sustainable urea production has directed attention toward electrocatalytic methods that bypass the energy-intensive traditional Haber-Bosch process. This study introduces an approach to urea synthesis through the coreduction of CO₂ and NO₃^- using copper-doped molybdenum diselenide (Cu-MoSe₂) with Cu-Mo dual sites as electrocatalysts. The electrocatalytic activity of the Cu-MoSe₂ electrode is characterized by a urea yield rate of 1235 μg h^-1 mg_cat.^-1 at -0.7 V versus the reversible hydrogen electrode and a maximum Faradaic efficiency of 23.43% at -0.6 V versus RHE. Besides, a continuous urea production with an enhanced average yield rate of 9145 μg h^-1 mg_cat.^-1 can be achieved in a flow cell. These figures represent a substantial advancement over that of the baseline MoSe₂ electrode. Density functional theory (DFT) calculations elucidate that Cu doping accelerates *NO₂ deoxygenation and significantly decreases the energy barriers for C-N bond formation. Consequently, Cu-MoSe₂ demonstrates a more favorable pathway for urea production, enhancing both the efficiency and feasibility of the process. This study offers valuable insights into electrode design and understanding of the facilitated electrochemical pathways.