(a) Screening results of TM@GY for the NRR based on the free energy changes of the first and last hydrogenation steps (ΔG(*N₂ → *N₂H) and ΔG(*NH₂ → *NH₃)), respectively. (b) The free energies for H and N₂ adsorption on all the TM@GY.

In this study, the key findings are that the para doped Mn₂@Ir(100) catalyst affords excellent NH₃ selectivity and NRR activity with an extremely low free energy barrier of 0.36 eV.

The electrocatalytic nitrogen reduction reaction (NRR) performed under ambient conditions has provided alternative routes to realize green NH ₃ synthesis. Herein, the process of NRR has been investigated on transition metal (TM = Fe, Co, and Ni) single atoms supported by B _n -doped (n = 1–3) graphyne (GY) using density functional theory (DFT) calculations. We successfully identified FeB@GY as an ideal electrocatalyst via the distal pathway with a minimum limiting potential of −0.53 V. Additionally, the FeB@GY surface can efficiently promote electron transfer efficiency and significantly improve the stability of intermediate adsorption during the NRR.