Direct Ammonia Synthesis from Nitrogen and Water at Mild Conditions

Direct ammonia (NH₃) synthesis from nitrogen (N₂) and water (H₂O) is a promising route for achieving energy-efficient NH₃ production by circumventing the energy-intensive H₂ production process, yet it is limited by unfavorable reaction thermodynamics. Herein, we report a direct ammonia synthesis process from N₂ and H₂O with CO as the oxygen acceptor to remove oxygen from H₂O over a Au/α-MoC_1-<i>x</i> catalyst, thereby bypassing the thermodynamic limitation of N₂ activation with H₂O under mild conditions. This process achieves NH₃ synthesis at temperatures as low as 100 °C, yielding 1396 μmol_NH₃ g_cat^-1 h^-1 of NH₃ at 320 °C. We disclose that the Au/α-MoC_1-<i>x</i> boundary offers Au^δ+ species for CO adsorption to vacate oxygen-covered Mo sites for N₂ adsorption and H₂O dissociation to OH* species, enabling stepwise N₂ hydrogenation to NH₃. This process enables direct ammonia synthesis from nitrogen and water through the synergistic cooperation of the oxygen acceptor and bifunctional Au/α-MoC_1-<i>x</i>.