Artificial N₂ fixation is one of the most important industrial processes for human beings. However, the current Haber-Bosch process based on fossil fuel suffers from unsustainability and a low N₂ to NH₃ conversion. Here, we report a magnesium chloride cycle for the synthesis of NH₃ from N₂ and H₂O at atmospheric pressure. In this cycle, N₂ reacts with Mg to form Mg₃N₂. Mg and Cl₂ are produced by the electrolysis of molten MgCl₂. NH₄Cl is used to hydrogenolyze Mg₃N₂ to produce NH₃, with anhydrous MgCl₂ being regenerated. The cycle is closed via the reverse Deacon reaction to convert Cl₂ to HCl, which is captured as NH₄Cl with the recyclable NH₃. This indirect electrosynthesis produces NH₃ at an industry-acceptable rate with zero CO₂ emission, a coulombic efficiency >92%, and an energy consumption of ∼14.1 kWh/kg-NH₃.

人工ñ ₂固定是人类最重要的工业生产过程中的一个。然而，当前基于化石燃料的哈伯-博世方法遭受不可持续性和从N ₂到NH ₃的低转化。在这里，我们报道了在大气压下由N ₂和H ₂ O合成NH _3的氯化镁循环。在该循环中，N ₂与Mg反应形成Mg ₃ N ₂。Mg和Cl ₂通过熔融MgCl ₂的电解产生。NH ₄ Cl用于水解Mg ₃ N ₂以产生NH_{如图3所示}，再生无水MgCl ₂。通过反向迪肯反应关闭循环，以将Cl ₂转化为HCl，并将其以NH ₄ Cl的形式被可回收的NH ₃捕获。这种间接的电合成以工业上可接受的速率产生NH ₃，其CO ₂排放为零，库仑效率> 92％，能耗约为14.1 kWh / kg-NH ₃。