Study of (Co)MoS2 1T-polytype for hydrotreating

SSCI-VIDE+ECI2D+SPL:DLA:PAFInternational audienceCrystals of MoS2 can exist as different polymorphs, displaying a range of electronic and optical properties, i.e. depending on the Mo-S coordination and the stacking order, it is possible to find three polytypes: 1T (Tetragonal), 2H (Hexagonal) and 3R (Rhombohedral). In the case of 2H and 3R polymorphs, each Mo has trigonal-prismatic coordination with the nearby S atoms, while for 1T-MoS2, Mo is coordinated in an octahedral manner.[1] Thanks to the particular behaviour exhibited by the 1T polymorph, it is considered as one of the most promising substitutes for metals in catalysis. Metallic 1T-MoS2 is distinct from semiconductor 2H and 3R polytypes due to its abundant active sites located not only at the edges but also in the basal planes. However, practical applications of 1T-MoS2 are greatly limited by its metastability, with an irreversible transformation to 2H stable phase induced by heating or simply by aging. Therefore, no study of 1T polymorph has been accomplished under hydrodesulfurization (HDS) conditions due to its metastable character. This work focuses on the stabilization of the 1T metallic phase under the hydrotreating conditions, which would offers metallic sites with different electronic properties, the ability of an active basal plane as well as the possibility of new properties when intercalation or promotion is also realized