Closing Electron Transfer Loop to Boost Electrocatalytic Urea Synthesis

Abstract

Abstract The electrocatalytic C─N coupling of carbon dioxide and nitrate presents a promising approach for environmentally friendly urea synthesis. In this work, we propose a strategy to boost efficient and durable urea synthesis by coupling the electrochemical and chemical steps. Utilizing fullerene (C 60 ) as a redox‐active electron mediator during the electrochemical reduction process, we effectively inhibit the irreversible reduction deactivation of positively charged copper (Cu δ+ ) active sites. The electron‐accepting fullerene form ions (C 60 n– ) that engage in a spontaneous chemical redox reaction with nitrate ions, producing nitrite ions and regenerating neutral C 60 (C 60 n– + NO 3 – → C 60  + NO 2 – ). This recycling mechanism closes the electron transfer loop while optimizing the overall reaction pathway. The urea yield rate is dramatically increased to 385.9 mmol h −1 g −1 , accompanied by long‐term durability. Our findings provide a valuable framework for designing highly efficient electrocatalyst for coupling reactions, advancing the field of sustainable urea synthesis.