Selective Urea Electrosynthesis from Nitrate and CO2 on Isolated Copper Alloyed Ruthenium

Urea electrosynthesis by coelectrolysis of NO₃^– and CO₂ (UENC) represents a promising method to enable efficient and sustainable urea production. In this work, isolated Cu alloyed Ru (Cu₁Ru) is developed as a highly active and selective UENC catalyst. Combined theoretical computations and in situ spectroscopic measurements reveal the synergistic effect of the Cu₁–Ru site and the Ru–Ru site on Cu₁Ru to promote the UENC via a tandem catalysis pathway, in which the Cu₁–Ru site drives *NO₂/CO₂ coupling and followed the *CO₂NO₂-to-*CO₂NH step. The formed *CO₂NH then migrates from the Cu₁–Ru site to the adjacent Ru–Ru site which promotes the *CO₂NH⃗*CO₂NH₂ → *COOHNH₂ steps toward urea generation. Impressively, Cu₁Ru achieves a high UENC performance in flow cell, exhibiting the urea yield rate of 21.04 mmol h^–1 g_cat^–1 and Faradaic efficiency of 51.27% at −0.6 V, outperforming most reported UENC catalysts.