Spatial Proximity in Single Atomic Co Sites Boosts Water‐Derived Active Hydrogen for Efficient Neutral Nitrate‐to‐Ammonia Electrosynthesis

ABSTRACT Single‐atom catalysts (SACs) are promising for nitrate reduction reaction (NO ₃ RR) to ammonia (NH ₃ ), given their high atomic efficiency and tunable, well‐defined structures. Yet, interactions between proximate atomic sites in NO ₃ RR are poorly understood. Here, we demonstrate the spatial proximity effect over N, P coordinated Co single atomic centers to boost NO ₃ RR catalytic activity. The adjacent configuration with CoN ₄ ‐P‐CoN ₄ atomic structures of the closest inter‐site distance of ∼4.5 Å balance the water dissociation and NO ₃ RR via a dual‐driven cascade mechanism in a neutral electrolyte. P site located at the shared second coordination shell dissociates water molecules to supply ample *H for the following hydrogenation process, while Co single site with optimized electronic state adsorbs and converts NO ₃ ⁻ to NH ₃ . This study underscores the critical role of spatial proximity in SACs for NO ₃ RR, and may extend to diverse electrochemical transformations.