Calculation of the activation barrier for CO dissociation on Cobalt Fischer-Tropsch Catalysts
renewable synthetic fuel
This is an example of a catalyst for “renewable synthetic fuel” using hydrogen derived from renewable energy and carbon dioxide as feedstocks.
Fischer-Tropsch (FT) reaction is a synthesis process of hydrocarbons from hydrogen and carbon monoxide, which involves a wide variety of elementary chemical reactions.
Cobalt and iron are used as catalysts.
CO dissociation is a critical part of the overall reaction mechanism for the FT process. In this example, we calculate the activation energy for CO dissociation on a cobalt catalyst.
○：Hydrogen ●：Oxygen ●：Carbon ●：Co catalyst
The model and method
Here we use the Nudged Elastic Band (NEB) method to calculate the activation energy of the CO dissociation reaction on the Co(0001) surface. The base model of the bulk crystalline cobalt structure is obtained from the Materials Project database .
The obtained bulk structure is cleaved to create the surface model for the NEB calculation. Once the Co(0001) surface is made, the initial state (IS) and the final state (FS) are constructed with adsorbed CO molecules.
Results and discussion
Matlantis is able to predict the activation energy of the CO dissociation with the same accuracy as in the previous literature. A conventional NEB calculation using DFT is often computationally very expensive, but it can be expedited by the application of PFP.
PFP can perform thousands of activation energy calculations in a realistic amount of time. Therefore, it is possible to explore a wide range of catalysts with high performance.
For example, vanadium(V) promoted cobalt surface created by substituting a V atom for a Co atom can promote the CO dissociation reaction. In fact, it is known experimentally that vanadium can promote FT reactions.[5, 6]
Because of the universality and blazing speed of PFP, it can be used not only to elucidate the chemical reaction phenomena, but also to screen materials from a huge chemical space.