An electrochemical route to green, decentralised ammonia: Advancing electrolytes and materials for lithium-mediated nitrogen reduction

About the Project

This PhD project will focus on investigating electrolyte and materials engineering to overcome stability, selectivity, and efficiency challenges in lithium-mediated nitrogen reduction, aiming to realise green, decentralised ammonia production as a sustainable alternative to the highly polluting Haber-Bosch process.

As a PhD researcher, you will explore a new sustainable and scalable electrochemical route to ammonia (NH3) from atmospheric nitrogen, the lithium-mediated nitrogen reduction reaction (Li-NRR) and other earth-abundant metals (M-NRR). Developing skills in electrochemical analysis and electrolyte materials chemistry, you will determine the factors controlling and limiting Li/M-NRR and apply this knowledge to advance the formulation of new and improved materials and conditions to address this critical sustainability challenge.

Ammonia is an essential chemical for fertilisers required for global food security and has potential as a zero-carbon fuel. However, NH3 production via the Haber Bosch process is one of the largest and most polluting chemical industries, accounting for >2% of human-made CO2 while being heavily centralised within developed countries. The Li/M-NRR is a room-temperature electrocatalytic reaction that could exploit the growing availability of renewable electricity, be significantly more scalable and, therefore, help to decentralise NH3 synthesis to improve fertiliser equity and security. Within Li-NRR, the reactive electroplated lithium can break the strong N2 triple bond, forming Li3N that reacts with labile protons to form NH3. However, while Li-NRR and Ca-NRR are the only routes proven conclusively to convert N2 to NH3 (Nature, 2019, 570, 504–508, Nat. Mater., 2024, 23, 101–107), there are restrictions to the current understanding of the chemistry and materials limiting reaction stabilities and efficiencies.

As a PhD student, you will join a team working towards the shared goal of advancing Li/M-NRR chemistry by understanding and optimising the underlying reaction mechanisms. This PhD project will work towards this goal by exploring the key electrolyte/material properties, developing new materials to overcome the challenges. First reported in 1930 (Helv. Chim. Acta 1930, 13 (6), 1228-1236.*), only recent efforts have demonstrated the potential of Li-NRR for NH3 production at scale. As such, there is a large material space to explore the electrolyte formulations, substrates, and proton carriers to (1) tune the critical electrolyte/electrode interface, interphases, and surface film properties (J. Am. Chem. Soc, 2025, 147, 33, 29687–29701), (2) control electrodeposition of reactive group1/2 metals (linking importantly with frontier battery chemistry research), (3) identify structure-property and formulation-property relationships, and (4) develop novel materials/parameters to optimise reaction selectivity and stability needed for green ammonia electrosynthesis.

You will be trained in electrochemical analysis, non-aqueous electrochemistry, air-sensitive chemistry, and spectroscopic characterisation, with opportunities to contribute towards cell/equipment design and development. This will be coupled with a variety of rigorous analytical methods to prove NH3 is a direct product from N2 reduction. As part of the wider team, you will have the opportunity to test electrochemical and material hypotheses using advanced operando/in situ spectroelectrochemical and microscopy techniques being developed in the group. Further, evaluation of material discoveries at larger scales will be targeted through collaborations with project partners.

As you explore the key electrolyte/material relationships towards enhancing Li/M-NRR, you will have the opportunity to communicate your findings through publications, as well as at national and international scientific meetings.