Til bevillingsoversigt

Ab-Initio screening and discovery of electrolyte compositions for nitrogen reduction to ammonia

Carlsbergfondets internationaliseringsstipendier

What

This project investigates a method to produce green ammonia from nitrogen. The reduction of nitrogen to ammonia is a critical process for plants in nature, for fertilizers and as a sustainable carbon free fuel. Today, the reaction happens via two routes: (i) the industrial Haber−Bosch process, (ii) the biological nitrogenase enzyme. The Haber−Bosch process is an efficient process and one of the most important catalytic reactions today. However, it emits huge amounts of CO2 due to consumption of hydrogen delivered by steam methane-reforming of fossil energy sources. This project explores a new route (iii) an electrochemical reduction in a lithium-mediate system, which avoids the need for hydrogen and can be powered by renewable electricity - hereby decrease CO2 emissions.

Why

Today, the lithium-mediated electrodes in a non-aqueous electrolyte have proven able to reduce N2 under electrochemical conditions. Despite the current research in system, it still suffers from poor performance. Interestingly, the Li-mediated system resembles the Li-ion battery; both systems contain Li-ions, organic electrolytes and both yield an ionically conducting solid electrolyte interface (SEI) between the electrode and the electrolyte. The complexity of the Li-mediated system all needed to work in unity, makes it extremely difficult to understand scientifically, getting a proper view on what is limiting the reaction and improving the system - to create a sustainable society of tomorrow.

How

I will work with leading scientists at Imperial College London; Professor Aron Walsh's who possess substantial computational materials insights and Dr. Ifan Stephens with experimental expertise in catalysis will complement my background in theoretical catalysis. We will show how the electrolyte compositions control the SEI layer to discover the best compositions and search for new materials. The tool to achieve these objectives is using Ab-Initio Molecular dynamics of electrolytes and Density Functional Theory of binding energies. An advantage of the proposed simulation type is that from an experimental point-of-view, it is relatively easy to change electrolyte components and measure the performance of the experiment; as such, there will be a strong tie between experiment and simulations.

SSR

This project searches for renewable energy technologies that could provide a more sustainable alternative than the society based on fossil fuels. The project can ideally show how fundamental research can be used to solve real societal problems, as sustainable production of green ammonia will directly decrease CO2 emissions today. This study is one step in creating the scientific advances required to create a sustainable society and the project outcome is essential to solving the challenges of the fossil fuel society today.