Enhanced Electrochemical Deuterated Ammonia (ND ₃ ) Production via Microenvironment‐Regulated Nitrate Reduction

Abstract Deuterated ammonia (ND ₃ ) has been widely used in pharmaceutical synthesis, chemical analysis, and semiconductor manufacturing, yet its conventional production suffers from high energy consumption, carbon emissions, and prohibitive costs. Here, an electrochemical approach is presented for ND ₃ production under ambient conditions, achieving industrial‐scale performance through microenvironment regulations. Using a highly dispersed iron catalyst on nitrogen doped carbon support for nitrate reduction in D ₂ O, the kinetic limitations of sluggish D ₂ O dissociation are partially mitigated, reaching 80% ND ₃ selectivity at 200 mA cm⁻ ² . By identifying key reaction intermediates through in situ spectroscopy and combining their interfacial modulation (via tetraethylammonium, TEA⁺) with deuterium supply optimization (via KD ₂ PO ₄ ), ND ₃ selectivity is further enhanced to 91%. Scaling the process to a 100 cm ² membrane electrode assembly (MEA) type electrolyzer demonstrates viability, yielding 23.1 mmol h⁻ ¹ ND ₃ at 85% selectivity (2.7 V, 5 A). Techno‐economic analysis confirms a 9 fold cost reduction to $6700–8700 per kg ND ₃ (8–11% of market price), alongside 20–71% lower emissions compared to conventional methods with life cycle analysis (LCA). This work establishes a sustainable, scalable route to ND ₃ production and addresses energy and environmental challenges in deuterated chemical synthesis.