Using DFT to screen for new catalysts for Fischer Tropsch synthesis : EU Fellowship

(a) Gain improved insight into the detailed mechanisms of Fischer-Tropsch catalysts: It is now well known that high pressures of CO and H2 induces large structural changes to the catalytic surface and that these self-organized surface structures are in fact responsible for the catalytic activity. Despite all experimental work on the subject, no entirely satisfactory reaction mechanism has been proposed, and in particular the parameters determining the selectivity of the catalyst are unknown. It is our belief that by detailed investigation of these systems using density functional calculations, we are going to be able to deduce details of the actual reaction mechanism and pinpoint the most important parameters determining the activity and more importantly the selectivity of the currently used catalysts.
(b) Screening for new possible Fischer-Tropsch catalysts using DFT: With detailed knowledge on parameters determining the selectivity we will use density functional theory for a very wide range of materials in a search for catalyst candidates that exhibit the desired properties, i.e. are highly selective towards desired reaction products. For catalyst materials exhibiting similar selectivity we expect to find materials capable of working at lower temperatures and/or that are less prone to poisoning effects and/or that have better stability in time. Finding materials with properties indicating a very high selectivity is very important as controlling the selectivity will allow for much greater reaction yield for the desired final products.
(c) Synthesis and characterization of new materials: Through collaboration with Prof. Christensen at the Department of Chemistry at the Technical University of Denmark we will try to synthesise the proposed catalyst materials and investigate their catalytic activity, both by kinetic evaluation and by in-situ techniques. By combining their experimental data with further computer simulations we hope to refine our search and further improve the properties of the proposed catalytic materials. It is important to point out that this part of the project involves close collaboration between theory and experiment, since a combined search more often than not is more successful than an isolated theoretical or experimental study.