Direct conversion of N₂ to nitrogen-containing organics via a plasma-electrochemical cascade reaction approaching...

The direct electrosynthesis of nitrogen-containing organic chemicals from N₂ is highly desirable for sustainable chemical manufacturing; however, its practical realization remains challenging due to the inherent inertness of N₂. To overcome this limitation, a novel plasma-electrochemical cascade strategy is developed for the direct synthesis of cyclohexanone oxime (CHO) from N₂ and cyclohexanone (CYC). The cascade strategy integrates the non-thermal plasma activation of N₂ to generate nitrogen oxides (NO_x) with the subsequent electrochemical reduction-coupling of NO_x to organic precursors. A specially designed arc discharge plasma device equipped with circular electrodes achieves a high NO_x concentration (957 mmol L^-1), providing a concentrated reactive feed for downstream electrochemical conversion. To promote efficient CHO formation, a Cu_SA-Mn_C@TiO₂ electrocatalyst is constructed to stabilize the *NH₂OH intermediate formed during NO_x reduction. Mechanistic studies confirmed NH₂OH as the key coupling intermediate, with Cu sites preferentially adsorbing *NO₂ and Mn sites adsorbing cyclohexanone. This synergistic effect enables excellent performance, achieving > 99% selectivity, a 99% CHO yield, and a production rate of 91.66 mmol g^-1 h^-1, which surpasses most previous N₂-to-chemical conversion systems. Therefore, this cascade strategy provides an efficient and promising route for the direct utilization of N₂ in the synthesis of valuable nitrogen-containing compounds.