Synthesis of Molybdenum Carbide and Formation of an Epitaxial Mo2c/MoS2 Hybrid Structure Via Carburization of Molybdenum Disulfide

The epitaxial formation of metallic molybdenum carbide (Mo 2 C, a 2D MXene material) is achieved via chemical conversion of molybdenum disulfide with thermal annealing under CH 4 and H 2. A fully converted metallic Mo 2 C and Mo 2 C/MoS 2 hybrid junctions could be provided with the adjusting of synthesis area of Mo 2 C the thermal annealing period. Mo 2 C film shows a metallic property as the outstanding electrode with a low sheet resistance (123.6 Ω/cm 2 ) and carrier concentration of 5.84Х10 13 /cm 2 . Mo 2 C/MoS 2 hybrid junctions display a low contact resistance (1.2 kΩ∙μm) and low Schottky barrier height (26 meV), indicating the material’s potential utility as a critical hybrid structural building block in future device applications. Mo 2 C grows and forms a Mo 2 C/MoS 2 hybrid structure were simulated by density functional theory calculations to model the mechanisms. The results show that Mo 2 C conversion is initiated at the MoS 2 edge and undergoes sequential hydrodesulfurization and carbide conversion steps, and an atomically sharp interface with MoS 2 forms through epitaxial growth of Mo 2 C. This work provides the area-controllable synthesis of a manufacturable MXene from a transition metal dichalcogenide (TMD) material and the formation of a metal/semiconductor junction structure. The present results will be of critical importance for future 2D heterojunction structures and functional device applications.