Mechanistic Insight into High Yield Electrochemical Nitrogen Reduction to Ammonia using Lithium Ions

06 August 2019, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Development of methods for economically feasible greener ammonia (NH3) production is gaining tremendous scientific attention. NH3 has its importance in fertilizer industry and it is envisaged as a safer liquid hydrogen carrier for futuristic energy resources. Here, an aqueous electrolysis based NH3 production in ambient conditions is reported, which yields high faradaic efficiency (~12%) NH3 via nitrogen reduction reaction (NRR) at lower over potentials (~ -0.6V vs. RHE or -1.1V vs. Ag/AgCl). Polycrystalline copper (Cu) and gold (Au) are used as electrodes for electrochemical NRR, where the electrolyte which yields high amount of NH3 (~41 µmol/L) is 5M LiClO4 in water with Cu as working electrode. A detailed study conducted here establishes the role of Li+ in stabilizing nitrogen near to the working electrode - augmenting the NRR in comparison to its competitor - hydrogen evolution reaction, and a mechanistic insight in to the phenomenon is provided. 15N2 assisted labeling experiments are also conducted to confirm the formation of ammonia via NRR. This study opens up the possibilities of developing economically feasible electrodes for electrochemical NRR at lower energies with only transient modifications of electrodes during the electrolysis, unlike the studies reported on complex electrodes or electrolytes designed for NRR in aqueous medium to suppress the hydrogen generation.


Heterogeneous Catalysis
Electrochemical Nitrogen reduction
Water in Salt


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.