Characterizing the Fischer-Tropsch Reaction over Flat and Stepped Cobalt Single Crystals at 1 bar

Industrial catalysis is both societally relevant for the products attainable through it (i.e., fertilizer, fine chemicals, and fuels) and transforming rapidly as a direct consequence to climate change and the reevaluation of resources together with CO₂ emissions in general. This also brings about the need to design catalysts that can work under lower pressures (i.e.,1 bar) and at lower temperatures, which fits ideally to the virtual pressure cell in the POLARIS setup [1].

In my talk, I will present a study of intermediates during the Fischer-Tropsch reaction over two single crystal surfaces of Co and Co. Herein we employ the Stockholm University POLARIS setup located at P22, DESY, PETRA III. Our findings indicate that the Co surface remains metallic at all conditions with only adsorbed species. There are a number of different intermediates on the surface, such as adsorbed CO in only on-top position, C/-CH intermediates, -CH₂– species and various longer hydrocarbon molecules. The coverage of the hydrocarbon species decreases with increasing temperature yet an increase with pressure is observed as well. Analyzing these intermediates allows us to discuss the reaction pathways. Utilizing the small size of the reactor volume in the virtual pressure cell (~0.1 mm³) we switch reaction conditions rapidly and follow the C 1s time evolution that underlines the activity of the surface under these conditions. Furthermore, this contribution will also give an overview of the recent work of the POLARIS activities aiming to summarize the last six years.