Continuous ammonia electrosynthesis using physically interlocked bipolar membrane at 1000 mA cm.

Electrosynthesis of ammonia from nitrate reduction receives extensive attention recently for its relatively mild conditions and clean energy requirements, while most existed electrochemical strategies can only deliver a low yield rate and short duration for the lack of stable ion exchange membranes at high current density. Here, a bipolar membrane nitrate reduction process is proposed to achieve ionic balance, and increasing water dissociation sites is delivered by constructing a three-dimensional physically interlocked interface for the bipolar membrane. This design simultaneously boosts ionic transfer and interfacial stability compared to traditional ones, successfully reducing transmembrane voltage to 1.13 V at up to current density of 1000 mA cm. By combining a Co three-dimensional nanoarray cathode designed for large current and low concentration utilizations, a continuous and high yield bipolar membrane reactor for NH electrosynthesis realized a stable electrolysis at 1000 mA cm for over 100 h, Faradaic efficiency of 86.2% and maximum yield rate of 68.4 mg h cm with merely 2000 ppm NO alkaline electrolyte. These results show promising potential for artificial nitrogen cycling in the near future.