Plasma-electrocatalytic synthesis of urea from air and CO2

Electrochemical C-N coupling of CO₂ with nitrogenous sources (e.g., N₂, NO₃^-) provides a promising method for urea production, whereas the current electrochemical methods are limited by low conversion efficiency or reliance on fossil fuel-derived NO₃^- feedstock. Here, we develop a plasma-electrocatalytic route for urea synthesis from ambient air and CO₂, which starts with plasma-assisted air activation to generate reactive NO_x^- (92.1% NO₂^-), followed by electrocatalytic co-reduction of CO₂ + NO_x^- to urea. By using a single-atom Ru₁/CuO_x catalyst in double chamber membrane electrode assembly, we achieve a urea yield rate of 106.9 mmol h^-1 g_cat^-1 and a Faradaic efficiency of 86.7%. This plasma-electrocatalytic route demonstrates a paradigm-shifting strategy for revolutionizing urea synthesis, making a great leap toward decarbonized nitrogen economy.