Multiscale simulations for the study of adsorption of dibenzothiophene on molybdenum disulfide nanoparticle catalysts

The adsorption of dibenzothiophene (DBT) on MoS₂ nanoparticles as a previous step to the catalytic activity in hydrodesulfurization (HDS) is studied with Dissipative Particle Dynamics (DPD) and Density Functional Theory (DFT) simulations. It is found that DBT exhibits both chemisorption and physisorption in its contact with the MoS₂ nanoparticle. As a result, there is an intermolecular electronic exchange that leads to the weakening of the C–S bonds of DBT and at the same time, the fact that the individual bonds between DBT and MoS₂ are not covalent, permitting the use of DPD to estimate the fraction of DBT molecules that can be physisorbed on MoS₂ nanoparticles in different solvents. Results reveal that the quality of the solvent and the structure of the nanocatalyst have an important influence on the adsorption efficiency, so multiscale modeling with DFT and DPD is a robust option for the study of these systems.