Understanding the Mechanism of Li-Mediated Nitrogen Reduction Reaction

Green ammonia production is a key environmental goal. As a crucial step towards this goal, a direct electrocatalytic N 2 reduction (eNRR) by protons and electrons emerges as a highly desirable alternative. However, all pragmatic attempts to develop such an electrochemical route have so far been hindered by invariably low selectivities and large overpotentials. The most reliable method presently is the lithium-mediated eNRR (LiNR) in non-aqueous electrolytes. 1 Despite significant progress made to achieve high FE and current density 2, 3 ,the mechanism of LiNR is yet not fully understood due to so many intricate processes involved ranging from the atomic scale to the macroscopic scale. Moreover, most Li-NRR studies have the limitations of using a sacrificial solvent as proton donors and difficulties in scaling up production in batch reactors. The talk will, address the long-term stability and high activity of PtAu in the HOR process by suppressing the unwanted THF oxidation and improving the tolerance towards CO-poison. Moreover, we investigate the mechanism of the LiNR from the ab initio atomistic reaction process, mean-field microkinetics, to the mass-transport simulations, explicitly achieving an improved understanding the dynamic change of the solid-electrolyte interphase in different LiNR reaction conditions and the effect on the performance. Reference: 1 J. Choi et al , Nat. Commun. 11 , 1–10 (2020) 2 K. Li, et al , Science 374, 1593-1597 (2021) 3 S. Li, et al , Joule, 6, 2083-2101 (2022)