A combined experimental and DFT study on the catalysis performance of a Co-doped MoS2 monolayer for hydrodesulfurization reaction

The removal of sulfur in diesel fuel requires efficient hydrodesulfurization catalysts during the upgrading process. However, although the traditionally prepared CoMoS catalyst is effective for hydrodesulfurization, it often is associated with problems such as a poor activity and deactivation susceptibility at high temperatures. In this work, chemical exfoliation and hydrothermal methods were employed to prepare MoS2 for modification with isolated Co atoms. The results showed that the prepared catalyst had a higher catalytic activity and could be used at lower temperatures. Subsequently, periodic density functional theory (DFT) calculations were used to discuss the effect of isolated Co doping on the catalytic performances of single-layer MoS2. DFT calculations revealed that the electronic structure of the MoS2 basal surface was changed by Co atom doping, making the originally inert basal surface catalytically active. Based on the energetic analysis, the influence of isolated Co atom doping on the adsorption performance, hydrogenolysis activity, and hydrodesulfurization performance of the basal surface is discussed. This work paves a new path for improving HDS catalytic activity via synergistic structure and charge characteristics.