Electrochemical Synthesis of Ammonia from Water and Nitrogen: A Lithium-Mediated Approach Using Lithium-Ion Conducting Glass Ceramics

Abstract

Lithium-mediated reduction of dinitrogen is a promising method to evade electron-stealing hydrogen evolution, a critical challenge which limits faradaic efficiency (FE) and thus hinders the success of traditional protic-solvent-based ammonia electro-synthesis. A viable implementation of the lithium-mediated pathway using lithium-ion conducting glass ceramics involves i)lithium deposition, ii)nitridation, and iii)ammonia formation. Ammonia was successfully synthesized from molecular nitrogen and water, yielding a maximum FE of 52.3%. With an ammonia synthesis rate comparable to previously reported approaches, the fairly high FE demonstrates the possibility of using this nitrogen fixation strategy as a substitute for firmly established, yet exceedingly complicated and expensive technology, and in so doing represents a next-generation energy storage system.