Growth of 2D-molybdenum disulfide on top of magnetite and iron by chemical methods

Systems based on the combination of ferromagnetic (FM) thin films and two-dimensional (2D) transition metal dichalcogenides are currently of high interest in the context of spintronic devices. Here, we report on the fabrication of MoS2/(Fe3O4, Fe) heterojunctions by using chemical-based methods. FM thin films have been initially synthesized on top of Si/SiO2 substrates by chemical vapour deposition. The 2D-MoS2 nanosheets have been grown on top of the FM layers by following the sulfurization of a solid film precursor of molybdenum oxide evaporated at the FMs surface. A comprehensive structural, chemical, morphological and magnetic characterization has been carried out at each step of the process. Several bottlenecks in the fabrication of MoS2 /(Fe3O4, Fe) systems have been evidenced, the most critical being the sulfurization process, in which we detect a pronounced tendency of S to react with the underlying FM layers. Our results could explain the limited functionalities often observed so far in spintronic devices based on 2D transition metal dichalcogenides, prompting some limits for their inclusion into practical devices.