Environmentally friendly and energy-efficient ways to produce ammonia are essential to meet global food demands. Here, a new approach for ammonia production at nominally ambient conditions is introduced. As proof of concept, ammonia is synthesized mechanocatalytically by ball milling titanium in a continuous gas flow. The ammonia synthesis reaction is proposed to follow a transient Mars− van Krevelen mechanism under mechanically activated conditions, where molecular nitrogen incorporation into the titanium lattice and titanium nitride hydrogenation occur in thermodynamically distinct environments. X-ray powder diffraction and X-ray absorption spectroscopy confirm the formation of titanium nitride from titanium and N 2 . The reactivity of nitrided titanium supports that lattice nitrogen plays a role in ammonia formation. The in situ formed titanium nitride is catalytically active, and the nitride regeneration reaction is determined to be the ratelimiting step. A preliminary technoeconomic analysis shows that this approach could be feasible for distributed ammonia production.

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Mechanocatalytic ammonia synthesis is a novel approach toward ammonia synthesis under mild conditions. However, many open questions remain about the various mechanism of mechanocatalytic ammonia synthesis as well as the...

Mechanocatalysis is a promising approach for green, solvent-free biomass deconstruction and valorization. Here, the hydrogenolysis of benzyl phenyl ether (BPE), a model lignin ether, via ball milling is demonstrated over...