Descriptor‐Driven Design of Dual‐Active‐Site Electrocatalysts for Ammonia Synthesis

Abstract The electrocatalytic nitrate reduction reaction (NO 3 RR) offers a sustainable route to convert nitrate (NO 3 − ) pollutants into value‐added ammonia (NH 3 ). However, the NO 3 RR process still suffers from sluggish kinetics due to unfavorable NO 3 − adsorption and limited active hydrogen (*H) availability. Optimizing NO 3 − adsorption and increasing *H supply can enhance catalytic performance, yet incorporating these improvements into the rational design of high‐performance catalysts remains challenging. Here, a descriptor‐guided intermetallic design strategy is proposed that synergistically integrates NO 3 − ‐adsorbing metal sites with *H‐supplying counterparts to enhance NO 3 RR performance. Density functional theory calculations indicate that Co possesses ideal NO 3 − adsorption energy, while Ge effectively supplies *H. By constructing atomic ordered Co‐Ge intermetallic compounds (IMCs), NO 3 − adsorption and *H supply are simultaneously optimized. Among seven thermodynamically stable Co‐Ge IMCs, hexagonal Co 7 Ge 4 ( h ‐Co 7 Ge 4 ) exhibits the most favorable limiting potential and NH 3 selectivity, identifying it as the most promising NO 3 RR electrocatalyst. Experimental results confirm that carbon‐supported h ‐Co 7 Ge 4 /C achieves a FE of 97.8% and good stability, outperforming most reported NO 3 RR electrocatalysts.