The lithium-mediated nitrogen reduction reaction (Li-NRR) represents a promising approach for electrochemical nitrogen activation, in which the solid electrolyte interphase (SEI) layer formed on the electrochemically plated lithium plays a key role. Herein, we used time-resolved, operando, grazing incidence wide-angle X-ray scattering (GI WAXS) to identify SEI species and reaction intermediates in the Li-NRR, comparing LiBF₄ and LiClO₄ as electrolyte salts. We demonstrated how the SEI composition influences the Li-NRR performance by regulating proton transport to the plated Li. When LiBF₄ is used as the electrolyte salt, the formation of LiF and lithium ethoxide (LiEtO) is observed. Reaction intermediates such as LiH and LiN_xH_y species were found and provide insight into reaction pathways towards undesired and desired products, respectively. Observed restructuring of the Cu (111) single crystal substrate also indicates interaction with plated Li that could possibly influence the Li-NRR performance. Together, these experiments give molecular insight into how to design Li-NRR systems and their SEI layers for optimal performance.

中文翻译：

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锂介导氮还原反应中固体电解质界面相的操作研究

锂介导的氮还原反应（Li-NRR）代表了一种有前途的电化学氮活化方法，其中电化学镀锂上形成的固体电解质中间相（SEI）层发挥着关键作用。在此，我们使用时间分辨、操作、掠入射广角 X 射线散射 (GI WAXS) 来识别 Li-NRR 中的 SEI 物质和反应中间体，并将 LiBF ₄和 LiClO ₄作为电解质盐进行比较。我们演示了 SEI 成分如何通过调节质子向镀锂的传输来影响 Li-NRR 性能。当使用LiBF ₄作为电解质盐时，观察到LiF和乙醇锂(LiEtO)的形成。发现了LiH 和 LiN _x H _y等反应中间体，并分别提供了对生成不需要的和所需的产物的反应途径的深入了解。观察到的 Cu (111) 单晶基底的重组也表明与镀锂的相互作用可能会影响 Li-NRR 性能。总之，这些实验为如何设计 Li-NRR 系统及其 SEI 层以实现最佳性能提供了分子视角。