Urea Electrosynthesis from Nitrate and CO on Diatomic Alloys.

Urea electrosynthesis from co-electrolysis of NO and CO (UENC) offers a promising technology for achieving sustainable and efficient urea production. Herein, a diatomic alloy catalyst (CuPdRh-DAA), with mutually isolated Pd and Rh atoms alloyed on Cu substrate, is theoretically designed and experimentally confirmed to be a highly active and selective UENC catalyst. Combining theoretical computations and operando spectroscopic characterizations reveals the synergistic effect of Pd-Cu and Rh-Cu active sites to promote the UENC via a tandem catalysis mechanism, where Pd-Cu site triggers the early C-N coupling and promotes *CONO-to-*CONH steps, while Rh-Cu site facilitates the subsequent protonation step of *CONH to *COOHNH toward the urea formation. Impressively, CuPdRh-DAA assembled in a flow cell presents the highest urea Faradaic efficiency of 72.1% and urea yield rate of 53.2 mmol h g at -0.5 V versus RHE, representing nearly the highest performance among all reported UENC catalysts.