STUDY OF POTASSIUM INTERCALATION IN TO THE GRAPHENE/MoS2 STRUCTURE

Using modern ab-initio calculations, in this work, we systematically studied the intercalation of potassium atoms into a hybrid two-layer graphene/ MoS2 structure. In the course of the study, concentrations of potassium atoms were determined at which the formation energy is negative. So, in particular, when the concentration of potassium atoms (in relation to molybdenum atoms) is not more than x=0,43, formation of a layer of potassium atoms between the graphene/ MoS2 layers is energetically favorable. Beginning with the concentration of potassium atoms x>0,75, an increase in the distance between the graphene and MoS2 layers is observed, which further leads to destruction of the structure. Calculation of charges showed that a potassium atom at low concentrations gives up about 0,8-0,85 electrons, 0,35 of which flow on carbon atoms, and 0,4-0,5 to molybdenum disulfide. Calculation of the difference in electron densities showed that the bond between the layers of graphene, molybdenum and potassium disulfide has a covalent nature.