Tackling the Activity Trend of Metal‐Loaded Metal Nitride Catalysts for NH₃ Synthesis by a First‐Principles Microkinetic Study

Abstract Ammonia (NH₃) is one of the most widely produced chemicals globally, primarily synthesized through the Haber‐Bosch process, which requires high temperatures and pressures. Dual‐site catalysts can activate N₂ and H₂ at spatially separated sites, enabling efficient NH₃ synthesis under milder conditions. Despite the rapid experimental progress of the dual‐site catalysts (e.g., Ni‐LaN), the feasibility and design of dual‐site catalysts are challenged recently. Herein, the different metal‐loaded metal nitride catalyst models are employed, and their activity map for NH₃ synthesis is explored by the first‐principles microkinetic simulation. The optimum active region of this type of dual‐site catalyst is identified in terms of the formation energy (E_v) of nitrogen vacancy (N_vac) on metal nitride and the adsorption energy (E_H) of hydrogen atom on metal cluster, with E_v and E_H ideally located around ≈1.50 and ≈−0.30 eV, respectively. This offers a framework for designing effective metal‐loaded metal nitride catalysts for NH₃ synthesis. Importantly, this trend aligns with and rationalizes the current experimental observations of metal‐loaded metal nitride reported for NH₃ synthesis. This theoretical work provides significant insights into NH₃ synthesis on dual‐site mechanism, and provides a rational direction for designing metal‐loaded metal nitride catalysts.