Rational Design of Conductive MOF-Based Diatomic Electrocatalysts for Selective Ammonia Synthesis

Diatomic catalysts (DACs) have recently attracted emerging attention beyond single-atom catalysts (SACs) in achieving targeted catalytic performance, yet their rational design and synthesis remain challenging. Here, we demonstrate the feasibility of designing DACs for highly selective ammonia synthesis from nitrate by developing a water-stable conductive metal-organic framework (cMOF) with a tunable Cu and Ni node (Cu_xNi_y-DBCO) used as a platform catalyst. The well-defined diatomic structure of the cMOFs and adjustable metal components enable systematic identification of active diatomic species and elucidation of the underlying nitrate reduction mechanism. Based on this understanding, we successfully design and synthesize a targeted DACs catalyst (Cu_98.5Ni_1.5-DBCO) to exhibit unit of selectivity accompanied with ammonia yields of over 200 mg h^-1 mg_cat^-1 (3.5 mmol h^-1 cm^-2) at a current density of >750 mA cm^-2. A Zn-NO₃^- battery incorporating this optimized DACs as the cathode delivers a power density of 35.6 mW cm^-2, highlighting the potential of conductive MOFs in developing target DACs for industrial electrocatalysis.