High-entropy-driven kinetic steering of urea electrooxidation enables coupled nitrite reduction for rapid urea-to-nitrogen conversion.

The electrochemical urea oxidation reaction (UOR) is thermodynamically favorable toward N2 formation. However, achieving selective N2 production is kinetically challenged due to the underlying multistep mechanism involving bond cleavage and N-N bond formation. Herein, we report a high-entropy-driven kinetic steering strategy that accelerates the intrinsically favored "cyanate" pathway and couples it with selective NO2- reduction to achieve rapid urea-to-nitrogen conversion. A high-entropy oxide, CeMoCuFeCoOx (CMCFCO), steers UOR toward fast C-N cleavage and NO2- formation via entropy-induced site isolation. Coupled with a S-CuFe cathode in a flowing single-chamber membrane-free electrochemical cell (EC), the generated NO2- is selectively reduced to N2, preventing NO2- accumulation. Without iR compensation, CMCFCO delivers 300 mA cm-2 at 1.69 VRHE, and exhibits a pseudo-first-order rate constant of 0.068 min-1, 2.6-4.0 times higher than low-entropy oxides. S-CuFe reaches 1.48 A cm-2 at -1.3 VRHE. At 300 mA cm-2 in 1.5 M KOH + 0.33 M urea, 92.7% urea removal is achieved within 40 min with 93.8% Faradaic efficiency toward N2 products. In situ spectroscopy and DFT reveal that high-entropy-induced site isolation accelerates cyanate formation, while interfacial *N coupling on S-CuFe promotes selective N2 generation. This reaction-coupling framework reconciles kinetic accessibility with thermodynamic selectivity in UOR.