Importance of Adatom on Pure Iron Catalyst Towards Electrocatalytic N Reduction Reaction.

The Haber-Bosch process using Fe-based catalysts is still the predominant technique for ammonia production despite tough reaction conditions and high energy consumption. In the present work, we have investigated iron adatom on the (110) surface of pure iron catalyst towards the electrocatalytic N reduction reaction (NRR) activity using density function theory (DFT) calculations. We demonstrate that the presence of adatom over the iron catalyst favours the NRR via alternating associative mechanistic pathway through a barrierless rate determining step (*NNH formation). Besides, the adatom-based catalyst requires lower working potential than the previously reported Fe(110) surface and Fe-nanocluster based catalysts. These findings may open a scope in terms of scrutinizing the atomicity effects over catalyst surface for various catalytic reactions.