Symbiosis of 1 T and 2H phases in the basal plane of defective MoS2 nanoflowers for efficient hydrodesulfurization

Hydrodesulfurization (HDS) is an effective way to reduce sulfur content in oil for the enforcement of more stringent environmental regulations. MoS2 has been widely used as an effective component for catalyzing HDS, and needs to be extensively studied in depth. Herein, MoS2 nanoflowers with the symbiosis of 1T-2H phases in the basal planes and coexistence of S and Mo vacancies are prepared via the assembly of many nanosheets by a one-pot solvothermal method. The morphology, crystal phase structure and defects of these 1T-2H MoS2 samples were well characterized. The 1T/2H ratio and the state of vacancies were effectively tuned by changing the solvothermal conditions. Active and stable 1T-2H mixed MoS2 nanoflowers with high content of 1T phase and moderate S and Mo vacancies were obtained by the regulation of oxalic acid in the mixture of ethanol and water. In the HDS of dibenzothiophene at 300 °C and 4 MPa, the optimal catalyst of MoS2-water–ethanol-OA exhibited a substrate conversion of 89.3% in 10 h. Moreover, the activity of MoS2-water–ethanol-OA was well retained without any decrease in the recycling experiment.