A new approach to producing ammonia using renewable electricity has overcome a fundamental energy limitation of the technology, opening new possibilities for cleaner and potentially more cost-effective production of one of the world’s most important chemicals.
Researchers from Monash University in Melbourne, Australia have developed a new type of lithium-alloying electrode that significantly reduces the energy required to convert nitrogen gas into ammonia, a breakthrough that could help advance the transition away from fossil-fuel-based ammonia production.
Ammonia is essential to global agriculture, particularly as the basis of nitrogen fertilisers, and is increasingly being explored as a carbon-free fuel and energy carrier. However, conventional ammonia production relies upon large, centralised facilities that cannot readily exploit geographically dispersed or stranded renewable energy.
Published in Cell Press Blue , the research tackles one of the major obstacles facing electrochemical ammonia production: energy efficiency.
The most established electrochemical approach uses lithium to help activate nitrogen gas, an exceptionally stable molecule that is otherwise difficult to convert into ammonia. While the method can produce ammonia at practical rates, its chemistry imposes an intrinsic limit on how energy-efficient the process can become.
The researchers, also working with colleagues at RMIT University, have now demonstrated that changing the chemistry of the cathode itself can overcome that limitation.
Lead author Dr Rebecca Hodgetts, from the Monash University School of Chemistry, said the new cathode materials effectively changed the boundaries of what was thought possible.
“Electrolytic synthesis of ammonia from renewables is possible, but present-day technology is fundamentally limited by low energy efficiencies and high costs,” Dr Hodgetts said.
“Our new cathode materials change the rules of the game by redefining this fundamental limit and opening up previously unexplored opportunities for more energy- and cost-effective production of green ammonia.”
Instead of producing lithium metal on a conventional electrode, the researchers used gallium-based materials that combine with lithium. This allows the lithium-mediated reaction to occur at substantially more favourable electrical potentials while retaining the ability to activate nitrogen and produce ammonia.
Under optimised experimental conditions, the researchers achieved ammonia production with a faradaic efficiency of 96 ± 6 per cent, meaning almost all the electrical current was directed towards producing ammonia.
The research findings could support future electrochemical ammonia production with an estimated energy efficiency of at least 22 per cent. While further improvements are required to reach proposed commercial targets, the researchers say the study provides proof-of-concept that the longstanding energy barrier can be overcome through electrode design.
Emeritus Professor Douglas MacFarlane, also with the School of Chemistry, said the discovery also expands the chemistry available to researchers working on renewable ammonia production.
“The field has essentially been limited to a single cathode process based on lithium-mediated nitrogen reduction,” Professor MacFarlane said.
“Introducing lithium-alloying materials broadens that chemistry considerably. Instead of being
constrained to one composition, we can begin exploring different combinations of materials capable of activating the extremely unreactive nitrogen molecule under relatively mild conditions.”
Professor Alexandr Simonov, also from the School of Chemistry, said the next challenge is translating the discovery from laboratory experiments into practical electrolysers.
“Our next key step is to integrate these new lithium-alloying cathodes into electrolyser prototypes that more closely mimic the conditions needed for practical ammonia production,” said Professor Simonov.
“We are also working to scale up the cathodes and demonstrate long-term ammonia production at competitive energy efficiency. That will be critical to taking this technology towards commercial application.”
The researchers say the work could ultimately contribute to more sustainable and decentralised ammonia production, using renewable electricity to produce ammonia closer to where it is needed whilst making use of geographically dispersed , or stranded renewable energy.
The technology is being further developed through ongoing research in collaboration with the Monash University spin-out company Jupiter Ionics Pty Ltd.
Cell Press Blue
Experimental study
Not applicable
Improved energy efficiency of nitrogen reduction to ammonia provided by lithium-alloying cathodes
8-Oct-2026