Nonaqueous Contact-Electro-Chemistry Enables C-N Coupling.

Contact electrification (CE) at solid-liquid interfaces generates interfacial charge separation capable of initiating chemical reactivity, yet its use for selective bond formation remains unexplored. Here we show that CE drives selective C-N coupling in a nonaqueous medium. Using dimethyl sulfoxide (DMSO) as both solvent and in situ CO source, mechanically induced CE in a polytetrafluoroethylene (PTFE)-DMSO system enables ambient urea synthesis from nitrate at 1817 μg g-1 h-1, comparable to photocatalytic systems. Unlike aqueous CE systems where proton-mediated electrical double layer screening dominates interfacial chemistry, the DMSO medium suppresses protonic side reactions and enhances selective nitrate activation. Urea formation depends strongly on nitrate solubility and interfacial ion availability, underscoring the role of the local ionic environment in governing CE reactivity. Experimental and density functional theory results suggest a mechanism involving interfacial electron transfer, DMSO-derived radical formation, and subsequent C-N coupling. This work establishes nonaqueous CE-Chemistry as a platform for selective mechanochemical synthesis under ambient conditions.