Steric Hindrance-Derived\nLi<sup>+</sup> Solvation\nto Enhance Lithium-Mediated Nitrogen Reduction

This study proposes\na steric hindrance-derived electrolyte (STE)\nto generate Li<sup>+</sup> anion-rich solvation structures to enhance\nthe Li-mediated nitrogen reduction reaction (Li-NRR), a promising\nelectrochemical green ammonia synthesis method. The STE applied methylation\nof the alpha proton in the tetrahydrofuran (THF) solvent, which dissolved\nlithium salts, leading to the weak solvation of Li<sup>+</sup> and\ngenerating an anion-rich-solvated structure. The resultant anion-derived\nsolid electrolyte interphase with thin and uniform inorganic properties\nimproved the selectivity, energy efficiency (EE), and stability of\nthe Li-NRR process. Additionally, the anion-rich solvation exhibited\nantireduction stability and inhibited electrolyte decomposition. Consequently,\nthe STE achieved a 2-fold increase in Faradaic efficiency and NH<sub>3</sub> yield rate (65.8% and 90.8 nmol cm<sup>–2</sup> s<sup>–1</sup>, respectively) compared to the THF-single electrolyte\n(35.7% and 49.3 nmol cm<sup>–2</sup> s<sup>–1</sup>)\nwhile increasing the EE by 1.5 times.