Electric-field-driven ammonia synthesis approaching industrial-level efficiency over a La2O3-supported Ru atomic cluster catalyst under mild conditions

Ammonia synthesis under mild conditions is critical for decarbonizing fertilizer production and enabling sustainable hydrogen carriers, yet remains a major challenge due to the lack of efficient catalysts and viable processes. This study presents an external electric field-driven ammonia synthesis strategy using Ru atomic clusters supported on La2O3, enabling efficient production under mild conditions. The system achieves industrial-grade ammonia output (17.8 vol%) at 200 °C, 4.0 MPa with a 92% reduction in energy consumption compared to conventional thermal catalysis (328 vs. 3681 kWh kg−1 NH3), far surpassing the high-temperature, high-pressure requirements of traditional Haber-Bosch process (> 400 °C, > 10 MPa). Mechanistic investigation reveals a dual-site catalyzed reaction pathway: the applied electric field enhances electron density at Ru sites, promoting N2 chemisorption and activation, while dynamically generating oxygen vacancies on La2O3 that facilitate H-spillover from Ru to La, thereby decoupling competitive H2/N2 adsorption and suppressing hydrogen poisoning; Furthermore, H2 cleavage at the RuLa interface is feasible, forming LaH species that act as cooperative active centers for associative nitrogen hydrogenation. This work pioneers a low-energy, distributed ammonia synthesis route compatible with renewable-powered water electrolysis and advances fundamental understanding of external field-driven catalysis.