Improving the Longevity of Li-Mediated Ammonia Synthesis via Pulsed Electrolysis under High Current Densities

, alongside a Faradaic efficiency of ca. 9% reaching 20% after constant potentiostatic recycling. The single-compartment cell design, in contrast to a conventional H-cell, indicated that ammonia crossover and anodic ammonia oxidation could substantially influence the apparent performance; we verified this by incorporating an ion-exchange separator and conducting control experiments focused on ammonia oxidation. Significantly, a pulsed operational technique that alternates rapid, intense negative cathodic pulses with anodic stripping pulses markedly reduced the rate of current density loss during recycling of the working electrode, suggesting improved control of solid-electrolyte interphase stability in the Li-NRR process. The cathode was successfully recycled across seven consecutive Li-NRR cycles with minimal structural degradation. This study provides insights into cell configurations and operational strategies that could improve the lifespan and selectivity of lithium-mediated ammonia synthesis.