Ni Triple-Atom Doped Cu₂O Electrocatalysts for Efficient Electrochemical Urea Synthesis: A Theoretical Study

Chemical C–N coupling from CO2 and N2 toward urea synthesis is an appealing approach for Bosch–Meiser urea production. However, this process faces significant challenges, including the difficulty of N2 activation, high energy barriers, and low selectivity. In this study, we theoretically designed a Ni triple-atom doped Cu2O catalyst, Ni TAC@Cu2O, which exhibits exceptional urea synthesis performance. Using density functional theory and the constant potential method, we show that the superior catalytic performance of Ni TAC@Cu2O stems from synergistic metal–support interactions (MSIs) between Ni atoms and Cu2O. Cu2O serves as an anchoring substrate and actively participates in CO2 activation via strong Cu–O bonding, whereas Ni serves as the pivotal active center for N2 activation. Ni TAC@Cu2O achieves a moderate N2 adsorption energy and a limiting potential (UL) of −0.60 V, overperforming Ni single-atom (Ni SAC@Cu2O, UL = −0.85 V) and Ni double-atom (Ni DAC@Cu2O, UL = −0.88 V) catalysts. The third Ni atom enhances electron donation, reducing the energy barrier of the rate-determining step (*CO + *N2 + H+ + e– → *CONNH), while O atoms in Cu2O regulate Ni's electronic structure through MSIs. Additionally, Ni TAC@Cu2O demonstrates thermodynamic, electrochemical, and acid–base stability and effectively suppresses competing side reactions. This work underscores the importance of Cu2O-supported MSIs in multiatom catalysts for enhanced performance and provides insights for advanced electrocatalyst design.