Characterisation and testing of novel electrodes and electrolytes for efficient N2 reduction

The current method for ammonia production, the Haber-Bosch process, consumes >1% of fossil fuels and emits vast quantities of greenhouse gas. Electrochemical ammonia synthesis, powered by renewable energy, could provide a green solution. However, there exist many significant contamination sources, complicating quantitative proof of synthesis. Additionally, any catalyst active for nitrogen reduction will preferentially evolve hydrogen [1].
This project will build on the recent first quantitative proof of ammonia synthesis using a lithium mediated route and an organic electrolyte [2]. The aim is to understand the role of the electrode and electrolyte using cutting-edge characterisation techniques translated from battery science. A magnetron sputter deposition chamber directly attached to a glove box will be used to grow highly reactive thin film electrodes. These can be quickly transferred to an electrochemical cell, minimising deleterious oxidisation. The glove box will contain a hypersensitive mass spectrometer to measure gas evolution in-situ, never used before for non-aqueous electrochemistry, and an infrared spectrometer to probe intermediates. These operando techniques will be complemented by various ex-situ characterisation methods, including secondary ion mass spectrometry, nuclear magnetic resonance spectroscopy, Raman spectroscopy and electrochemical atomic force microscopy. The emergent molecular-scale picture will elucidate pathways towards efficient electrochemical ammonia synthesis.

[1] Nilsson, A. & Stephens, I. E. L. "Sustainable N2 reduction" in Research needs towards sustainable production of fuels and chemicals (eds J.K. Norskov, A. Latimer, & C. F. Dickens) 49 (Energy-X, Brussels, Belgium, 2019)
[2] Andersen, S. Z., Colic, V., Yang, S., Schwalbe, J. A., Nielander, A. C., McEnaney, J. M., Enemark-Rasmussen, K., Baker, J. G., Singh, A. R., Rohr, B. A., Statt, M. J., Blair, S. J., Mezzavilla, S., Kibsgaard, J., Vesborg, P. C. K., Cargnello, M., Bent, S. F., Jaramillo, T. F., Stephens, I. E. L., Norskov, J. K. & Chorkendorff, I. Nature 570, 504, (2019)

The production and processing of materials accounts for 15% of UK GDP and generates exports valued at £50bn annually, with UK materials related industries having a turnover of £197bn/year. It is, therefore, clear that the success of the UK economy is linked to the success of high value materials manufacturing, spanning a broad range of industrial sectors. In order to remain competitive and innovate in these sectors it is necessary to understand fundamental properties and critical processes at a range of length scales and dynamically and link these to the materials' performance. It is in this underpinning space that the CDT-ACM fits.

The impact of the CDT will be wide reaching, encompassing all organisations who research, manufacture or use advanced materials in sectors ranging from energy and transport to healthcare and the environment. Industry will benefit from the supply of highly skilled research scientists and engineers with the training necessary to advance materials development in all of these crucial areas. UK and international research facilities (Diamond, ISIS, ILL etc.) will benefit greatly from the supply of trained researchers who have both in-depth knowledge of advanced characterisation techniques and a broad understanding of materials and their properties. UK academia will benefit from a pipeline of researchers trained in state-of the art techniques in world leading research groups, who will be in prime positions to win prestigious fellowships and lectureships. From a broader perspective, society in general will benefit from the range of planned outreach activities, such as the Mary Rose Trust, the Royal Society Summer Exhibition and visits to schools. These activities will both inform the general public and inspire the next generation of scientists.

The cohort based training offered by the CDT-ACM will provide the next generation of research scientists and engineers who will pioneer new research techniques, design new multi-instrument workflows and advance our knowledge in diverse fields. We will produce 70 highly qualified and skilled researchers who will support the development of new technologies, in for instance the field of electric vehicles, an area of direct relevance to the UK industrial impact strategy.
In summary, the CDT will address a skills gap that has arisen through the rapid development of new characterisation techniques; therefore, it will have a positive impact on industry, research facilities and academia and, consequently, wider society by consolidating and strengthening UK leadership in this field.