Looking below the surface: Revealing Interfacial Reactions for Sustainable Electrochemical Technologies

One of the greatest challenges of our time is to rapidly transition towards a low-carbon economy in order to limit the extent of climate change. The UK government's pledge to achieve net-zero emissions by 2050 will require decarburisation across all sectors, and thus the development of new technologies to ensure secure, reliable energy supplies are maintained. The expansion of solar and wind power has resulted in renewable energy costs that are competitive with or even undercut fossil fuel alternatives. However, further transition to renewable energy sources will require major changes in how we convert, store and use energy, including measures to deal with their intermittency and increased electrification. Electrochemical conversion technologies will be central to decarbonising the chemical industry, offering potential improvements in efficiency compared to current thermocatalytic processes. However, improved electrocatalyst materials are needed to achieve the performance and cost that large-scale deployment requires. Rational design of these catalysts demands an understanding of the nature of the reactions occurring on their surfaces during use. Although we can currently study these materials post-mortem, this tells us little about the reactions that occurred during their active life. This fellowship renewal builds on a suite of innovative characterisation techniques that enable chemical reactions occurring at the buried interfaces in electrochemical devices to be directly observed during operation. By using windows that are transparent to X-rays and electrons, the atomic-scale processes occurring on the surface of electrocatalysts for producing valuable chemicals will be revealed without disturbing the liquid environments in which they operate. This will enable the limitations of existing material combinations to be understood, and for new material solutions to be identified and tested. These approaches will now be used to reveal how local environment influences electrocatalyst performance for the carbon dioxide reduction reaction, including the role of solvation in concentrated electrolytes, and the influence of different reaction cell formats. It will also extend to study electrochemical production of ammonia, building on our work with Li-ion batteries, to provide important new insight in this emerging area. The proposed approach will improve our understanding of how ions and solvents arrange at electrochemical interfaces in concentrated solutions, and the resulting impact on the electrochemical reactions occurring. The understanding developed through this program of research is expected to inform the design of low-cost, earth-abundant catalysts for the production of carbon-neutral liquid fuels and chemicals. These advances will reduce our reliance on fossil fuel extraction, ultimately helping to tackle long-term challenges such as climate change.